Disorders of hemostasis (platelet and coagulation).
Interventions for clients with inherited and acquired disorders of hemostasis
The hematologic system is composed of the blood, blood cells, lymph, and organs concerned with blood formation or blood storage. Because all systems depend on circulation and lymph flow, any problem of the hematologic system has widespread consequences for health and well-being. This chapter review the normal physiology of the hematologic system and the assessment of hematologic status.
ANATOMY AND PHYSIOLOGY REVIEW
Bone Marrow. Bone marrow is the blood-forming (hematopoietic) organ. It produces most of the cellular elements of the blood, including red blood cells (RBCs, erythrocytes), white blood cells (WBCs), and platelets. Bone marrow also is involved in some aspects of the immune response. Each day, the bone marrow in a healthy adult produces and releases approximately 2.5 billion RBCs, 2.5 billion platelets, and 1 billion white blood cells (leukocytes) per kilogram of body weight. In the fetus, blood components are formed in the liver and spleen and, by the last trimester, in the bone marrow. At birth, blood-producing marrow is present in every bone. The flat bones (sternum, skull, pelvic and shoulder girdles) contain active blood-producing marrow throughout life. As a person ages, the amount of functional bone marrow decreases in the long bones and in small, irregularly shaped bones. By age 18 blood production is limited to the ends of the long bones. During adulthood, fatty tissue replaces inactive bone marrow. In older adults, the proportion of fatty marrow increases to approximately one half of the marrow found in the sternum and ribs, and only a relatively small portion of the remaining marrow continues active blood production.
The bone marrow produces all blood cells, which initially start out as stem cells. Bone marrow contains pluripotent stem cells. Pluripotent stem cells are immature and undifferentiated cells that are capable of maturing into any one of several types of blood cells: RBCs, WBCs, or platelets, depending on the body’s needs (Figure 39-1).
The next stage in cell development is the committed stem cell (also called the precursor cell or unipotent stem cell). A committed stem cell has one specific maturational pathway and matures or differentiates into only one cell type. Committed stem cells actively divide but require the presence of a specific growth factor for further development and maturation. For example, erythropoietin is a growth factor made in the kidneys that is specific for the red blood cell line. Many different growth factors influence the maturation of white blood cells and platelets.
Blood Components
Blood is composed of plasma and cells. Plasma, part of the extracellular fluid of the body, is similar to the interstitial fluid found between tissue cells. Plasma, however, contains about three to four times more protein than does interstitial fluid. There are three major types of plasma proteins: albumin, globulins, and fibrinogen. The primary function of albumin is to increase the osmotic pressure of the blood, which prevents plasma from leaking into the tissues. Globulins perform many functions, such as transporting other substances and protecting the body against infection. Globulins are also the main component of antibodies. Fibrinogen is a protein molecule that can be activated to form fibrin. Individual molecules of fibrin assemble to form large structures important in the blood-clotting process.
The cells of the blood include RBCs, WBCs, and platelets. These blood cells differ in structure, site of maturation, and function.
RED BLOOD CELLS (ERYTHROCYTES)
Red blood cells (RBCs), or erythrocytes, make up the largest proportion of blood cells. Mature RBCs have no nucleus and have a biconcave disk shape. Together with a flexible membrane, this feature allows RBCs to change their shape without breaking as they pass through narrow, winding capillaries. The number of RBCs a person has varies according to gender, age, and general health, but the normal range is from 4.4 to 5.5 million/mm3. As shown in Figures 39-1 and 39-2, RBCs start out as pluripotent stem cells, enter the myeloid pathway, and progress in stages to the mature RBC (the erythrocyte).
Healthy, mature RBCs have a life span of approximately 120 days after being released into the blood from the bone marrow. As RBCs age, their membranes become more fragile. These old cells are trapped and destroyed by fixed macrophages in the tissues, spleen, and liver. Some parts of destroyed RBCs (e.g., iron) are recycled and used in the formation of new RBCs. RBCs are responsible for producing hemoglobin (Hgb). Each normal, mature RBC contains many thousands of hemoglobin molecules (Guyton & Hall, 2000). The heme part of each hemoglobin molecule requires a molecule of iron. Only when the heme molecule is complete with iron can it transport up to four molecules of oxygen. Therefore iron is a critical component of hemoglobin.
The globin portion of the hemoglobin molecule carries carbon dioxide. RBCs also serve as a buffer and help maintain acid-base balance. The most important feature of the hemoglobin molecule is its ability to combine loosely with oxygen. With only a small drop in oxygen concentration at the tissue level, a greater increase in the transfer of oxygen from hemoglobin to the tissues occurs. This transfer is also known as oxygen dissociation. Some pathologic conditions change the speed and amount of oxygen released to the tissues.
The total number of RBCs is carefully controlled through erythropoiesis (selective maturation of stem cells into mature erythrocytes). This process ensures that enough RBCs are present for good oxygenation without having an excess concentration, which could “thicken” the blood and slow its flow. The trigger for control of erythropoiesis is tissue oxygenation. The kidney produces the RBC growth factor erythropoietin at the same rate as RBC destruction to maintain a constant normal level of circulating RBCs. When tissue oxygenation is less thaormal (hypoxia), the kidney increases the production and release of erythropoietin. This growth factor stimulates the bone marrow to increase RBC production. When tissue oxygenation is excessive, the kidney decreases the production erythropoietin, inhibiting the production of RBCs. Synthetic erythropoietin (Procrit, Epogen, EPO) is now available and appears to have the same effect on bone marrow as naturally occurring erythropoietin.
Many substances are needed to form hemoglobin and RBCs, including iron, vitamin B12, folic acid, copper, pyridoxine, cobalt, and nickel. A lack of any of these substances can lead to anemia. Anemia is the result of any condition in which either the function or the number of erythrocytes is inadequate to meet tissue oxygen demands.
WHITE BLOOD CELLS (LEUKOCYTES)
White blood cells (WBCs), or leukocytes, are the second category of blood cells. There are many types of leukocytes, and each type performs at least one specific action critical to inflammation or immunity (Table 39-1).
Most WBCs are formed in the bone marrow and are considered part of the hematopoietic system. A detailed discussion of leukocyte anatomy and function is presented in Chapter 20, because these cells provide immunity and protect against the effects of invasion, infection, and injury.
PLATELETS
Platelets are the third type of blood cells. They are the smallest of the blood cells and are formed as fragments of a giant precursor cell in the bone marrow, the megakaryocyte. Figure 39-1 shows the overall developmental pathway of blood cells, and Figure 39-3 shows specific platelet development.
Platelets stick to injured blood vessel walls and form platelet plugs that can stop the flow of blood from the injured site. They also produce substances important to coagulation. Platelets maintain blood vessel integrity by beginning the repair of damage to small blood vessels. They perform most of their functions by aggregation (clumping). Platelet production in the bone marrow also is precisely controlled by growth factors (thrombopoietin). After platelets leave the bone marrow, they are taken up by the spleen for storage and are released slowly according to the body’s needs. Normally, 80% of platelets circulate and 20% are stored in the spleen. Each platelet has a life span of 1 to 2 weeks, after which it is gradually used up or destroyed during normal clotting activities.
Accessory Organs of Hematopoiesis The spleen and liver are important accessory organs of the hematopoietic system. They help regulate the maturation of blood cells to help maintain hematologic homeostasis.
SPLEEN
The spleen is located under the diaphragm to the left of the stomach. It contains three types of tissue—white pulp, red pulp, and marginal pulp—all of which help to balance blood cell production with blood cell destruction and assist with immunologic defensive mechanisms. White pulp is filled with lymphocytes and macrophages. As whole blood circulates and filters through the white pulp, unwanted cells (e.g., bacteria and old RBCs) are removed. Red pulp is composed of vascular enlargements (sinuses) that are storage sites for RBCs and platelets. Marginal pulp contains the ends of many arteries and other blood vessels. During blood formation, the spleen destroys old or imperfect RBCs, assists in iron metabolism by breaking down the hemoglobin released from these destroyed cells, stores platelets, and filters antigens. A client who has undergone a splenectomy experiences an impairment of some immune functions. Thus after a splenectomy, the body is not efficient at disposing of many bloodborne pathogenic microorganisms and is at a greatly increased risk for infection and sepsis (Workman, 1998).
LIVER The liver is important for normal erythropoiesis and is the primary production site for prothrombin and most of the bloodclotting factors. In addition, proper liver function and bile production are critical to the formation of vitamin K in the intestinal tract. (Vitamin K is essential in the formation of blood-clotting factors VII, IX, and X and prothrombin.) Large quantities of whole blood and blood cells can be stored in the liver. The liver also converts bilirubin (one end-product of hemoglobin breakdown) to bile and stores extra iron within a storage protein called ferritin. Small amounts of erythropoietin are produced in the liver.
Hemostasis/Blood Clotting In hemostasis, selective localized blood clotting occurs in damaged blood vessels while blood circulation to all other areas is maintained. Hemostasis is a complex process that balances the production of clotting and dissolving factors. It begins with the formation of a platelet plug and continues with a series of events that eventually cause the formation of a fibrin clot. Intrinsic and extrinsic factors are involved in fibrin clot formation and blood coagulation. Three sequential processes result in blood clotting: platelet aggregation with formation of a platelet plug, the blood-clotting cascade, and the formation of a complete fibrin clot.
PLATELET AGGREGATION The formation of a platelet plug by causing platelets to aggregate (clump) together is a key requirement for blood clotting. Platelets normally circulate as individual cell-like structures. They are not attracted to each other and do not clump together until activated or until the presence of other substances causes platelet membranes to become sticky, allowing aggregation to occur. When platelets become activated and aggregate, they form large, semisolid plugs within the lumens and walls of blood vessels and disrupt blood flow. These platelet plugs are not clots and cannot provide complete hemostasis. Some substances that cause platelets to aggregate include adenosine diphosphate (ADP), calcium, thromboxane A2, and collagen. Platelets themselves can be stimulated to secrete some of these substances, whereas other substances causing platelet aggregation are exogenous. Formation of a platelet plug starts the cascade reaction that ultimately causes blood coagulation to occur through formation of a fibrin clot.
THE BLOOD-CLOTTING CASCADE The blood-clotting cascade is triggered by the formation of a platelet plug. Platelet plug formation results from intrinsic or extrinsic factors. The beginning of this cascade is rapidly amplified or enhanced, with the final result much larger than the triggering event. Cascades work like a landslide. A few small pebbles rolling down a steep hillside can dislodge large rocks and pieces of soil, causing a final enormous movement of earth. As with landslides, cascade reactions are hard to stop once set into motion. Intrinsic Factors Intrinsic factors are problems or substances directly in the blood itself that first make platelets aggregate and then proceed to activate the blood-clotting cascade (Figure 39-4).
Intrinsic events that stimulate platelet aggregation include antigen- antibody reactions, circulating debris, prolonged venous stasis, and bacterial endotoxins. Continuation of the cascade to the point of fibrin clot formation depends on the presence of sufficient amounts of all the various clotting factors and cofactors (Table 39-2).
Extrinsic Factors Platelet plugs can begin to form as a result of changes in the blood vessels rather than changes in the blood. When platelet plugs form in response to blood vessel changes, the response is said to be caused by extrinsic factors (extrinsic to the blood). The most common extrinsic events are trauma to tissues and damage to blood vessels, which exposes the platelets to collagen and stimulates aggregation. The platelet plug is formed within seconds of the trauma. The blood-clotting cascade is started sooner by the extrinsic pathway than by the intrinsic pathway because some of the steps of the intrinsic pathway are bypassed. Whether the platelet plugs were formed because of abnormal blood (intrinsic factors) or by exposure of substances from damaged blood vessels (extrinsic factors), the end result of the cascade is the same: formation of a fibrin clot and coagulation. The many steps of the cascade between the formation of a platelet plug and the formation of a fibrin clot are dependent on the presence of specific clotting factors, calcium, and more platelets. Clotting factors (see Table 39-2) are actually inactive proteins that become activated in a sequence to activate fibrinogen into fibrin. At each step, the activated protein from the previous step allows activation of the next protein. The last two steps in the cascade are the activation of thrombin from prothrombin and the conversion (by thrombin) of fibrinogen into fibrin. Only fibrin molecules can begin the formation of a true clot.
FIBRIN CLOT FORMATION Fibrinogen is a large, inactive protein molecule made in the liver and secreted into the blood. Thrombin, an enzyme, removes the end portions of fibrinogen and converts it to the active fibrin molecule. Individual fibrin molecules link together to form fibrin threads. The fibrin threads make a lattice-like meshwork that forms the base of a blood clot (Figure 39-5).
After the fibrin mesh is formed, a stabilizing factor (clotting factor XIII) tightens up the mesh, making it more dense. Additional platelets stick to the threads of the mesh and attract other blood cells and proteins to form an actual blood clot. As this clot retracts, the serum (plasma without the clotting factors) is excreted, and clot formation is complete.
FIBRINOLYSIS Because blood coagulation occurs through a rapid cascade process, in theory it keeps forming fibrin clots whenever the cascade is set into motion until all blood throughout the entire body has coagulated. Such widespread coagulation is not compatible with life. Therefore, when the blood-clotting cascade is started, counterclotting or anticoagulant forces are also started to limit clot formation to only damaged areas; normal blood flow is maintained everywhere else. When blood clotting and anticlotting actions are appropriately balanced, coagulation occurs only where needed, and normal circulation is maintained. The fibrinolytic system dissolves the fibrin clot with special enzymes (Figure 39-6).
The key event of fibrinolysis is the conversion of plasminogen to plasmin. Plasmin, an active enzyme, digests fibrin, fibrinogen, prothrombin, and factors V, VIII, and XII, thus breaking down the fibrin clot.
Hematologic Changes Associated with Aging Aging changes the cellular and plasma components of blood, making accurate assessment of the hematologic system in older adults more difficult. Chart 39-1 lists assessment tips for this population.
Several factors cause a decreased blood volume in older people. Total body water is decreased among older adults. In addition, they tend to have a lower concentration of plasma proteins and a decreased plasma osmotic pressure (possibly related to a decreased dietary intake of proteins), which also causes some loss of blood volume into the interstitial space. Bone marrow produces fewer blood cells as it ages. Total red blood cell (RBC) and white blood cell (WBC) counts (especially lymphocyte counts) are lower among older adults. Platelet counts do not appear to change with age. Lymphocytes become less reactive to antigens and have a loss of im mune function. Antibody levels and responses are lower in older adults. The leukocyte count does not rise as high in response to infection in older people as it does in young people (Workman, Ellerhorst-Ryan, & Koertge, 1993). Hemoglobin levels also change with age. Hemoglobin levels in men and women fall after middle age. Iron-deficient diets may play a role in this phenomenon.
Anticoagulants and Thrombolytics Drug therapy is commonly used to alter clotting ability or to destroy existing clots when circulation is at risk. The two broad categories of drugs are anticoagulants and thrombolytics. Both categories of agents are used widely to treat excessive or inappropriate clot formation, but their actions, side effects, and precautions are very different.
ANTICOAGULANTS Anticoagulant drugs exert their effects by interfering with one or more steps in the blood-clotting cascade. Thus these agents prevent the formation of new clots and limit or prevent the extension of formed clots. Anticoagulants have no degradative effects on existing clots. Anticoagulants are further categorized into heparin, vitamin K antagonists, and platelet aggregation inhibitors. Table 39-3 summarizes the actions of different anticoagulants. Figure 39-4 shows where in the blood-clotting cascade these agents exert their anticlotting effects.
THROMBOLYTICS Thrombolytic agents preferentially degrade fibrin threads already present in the formed blood clot. The four most extensively used agents are tissue plasminogen activator (t-PA), streptokinase (SK), reteplase, and anistreplase. The mechanism to start fibrin degradation is the activation of the inactive tissue protein plasminogen to its active form, plasmin. Plasmin directly attacks and degrades the fibrin molecule and has fewer effects on the fibrinogen molecule. The general action of all these thrombolytic agents is the selective degradation of formed fibrin clots with minimal effect on clot formation.
In general, the administration of thrombolytic agents results in clot breakdown with less disruption of blood clotting. Thrombolytic agents are the first-line therapy for conditions caused by existing small or localized formed clots, such as myocardial infarction, limited arterial thrombosis, thrombotic strokes, and occluded shunts. For some conditions (e.g., myocardial infarction), these drugs are given only within the first 6 hours after the onset of symptoms. This time limitation is not related to drug activity, because thrombolytic agents can break down clots older than 6 hours. Rather, tissue that has been anoxic for more than 6 hours is not likely to benefit from this therapy, making the risks to the client greater than the advantages.
Thrombolytic therapy has a very limited role when clotting is extensive, such as in deep vein thrombophlebitis within the pelvis or massive pulmonary emboli. In these situations clots are very large compared to their usual size in the coronary arteries. The amount of drug and duration of therapy needed for the effective breakdown of such clots is both cost prohibitive and physiologically risky. Many of these clots are not easily accessed for direct infusion of the thrombolytic agent. In addition, these clots are large, and the danger of releasing largesized particles from the clots during breakdown and having them occlude other blood vessels is much greater than the thrombolytic therapy of smaller arterial clots.
ASSESSMENT TECHNIQUES
History
DEMOGRAPHIC DATA Chart 39-2 lists questions based on Gordon’s Functional Health Patterns to ask during the assessment of hematologic function. Age and gender are important variables to obtain when assessing the client’s hematologic status. Bone marrow and immune activity diminish with ag It is also important for the nurse to collect information on the client’s occupation, hobbies, and location of housing. This information may indicate an exposure to agents or chemicals that affect bone marrow growth and hematologic function.
PERSONAL AND FAMILY HISTORY Obtaining an accurate family history is important because many bleeding disorders are inherited. The nurse asks whether anyone in the family has had hemophilia, frequent nosebleeds, postpartum hemorrhages, excessive bleeding after tooth extractions, or continuous heavy bruising in response to relatively mild trauma. Family information about sickle cell disease or sickle cell traits also is obtained. Although sickle cell disease is seen primarily among African Americans, anyone may have the trait. Personal factors to be included in the hematologic assessment are liver function, the presence of known immunologic or hematologic disorders, and current medication use. Because liver function is important in the synthesis of clotting factors, the nurse also asks about jaundice, anemia, and gallstones.
The client is asked about use of blood “thinners” such as sodium warfarin (Coumadin, Warfilone), aspirin, and other nonsteroidal anti-inflammatory drugs (NSAIDs). A person who takes aspirin on a daily basis may have bleeding problems, and many over-the-counter medications contain aspirin or other salicylates that disrupt platelet aggregation. The nurse determines all medications that the client is using or has used in the past 3 weeks. Clients are also asked about the use of antibiotics, because prolonged antibiotic therapy can lead to coagulopathies or bone marrow depression. Table 39-4 lists drugs known to alter hematologic function. Previous radiation therapy may result in some permanent impairment of hematologic function, especially if marrow-forming bones were in the path of the radiation.
DIET HISTORY Dietary pattern can alter cell quality and affect blood clotting. The nurse asks clients to record everything eaten during the previous week. This information is helpful in determining the causes of anemias and of protein, mineral, or vitamin deficiencies. Diets high in fat and carbohydrates and low in protein, iron, and vitamins can cause many types of anemia and decrease the functions of all blood cells. Clients are asked about alcohol consumption. Chronic alcoholism is associated with nutritional deficiencies and liver impairment, both of which can decrease the ability of the blood to clot. Certain dietary habits can enhance blood clotting. Diets high in vitamin K may increase the rate of blood coagulation. The nurse assesses the amount of raw, leafy green vegetables that the client consumes and whether he or she routinely takes supplemental vitamins. The amount of calcium consumed within the diet or in supplements is also assessed.
SOCIOECONOMIC STATUS The nurse assesses the client’s ability to understand and follow instructions related to proper diet, specific procedures and tests, and therapeutic regimens. Personal resources, such as finances and social support, are determined. A person with a marginal income may have a diet low in iron and protein. The nurse also notes the client’s occupation and asks about potential exposure to chemicals.
CURRENT HEALTH PROBLEMS The nurse determines whether the client has experienced swelling of the lymph nodes or excessive bruising or bleeding and whether the bleeding was spontaneous or induced by trauma. The client is asked about the amount and duration of bleeding after routine dental work. Women are asked about the presence of menorrhagia (excessive menstrual flow). They are asked to estimate the number of pads or tampons used during the most recent menstrual cycle and whether this amount represents a change from their usual pattern of menstrual flow. The nurse asks whether clots are present in menstrual blood. Clot size is estimated using coins or fruit for comparison (“clots are dime sized” or “clots are the size of lemons”). The nurse determines whether the client experiences dyspnea on exertion, palpitations, frequent infections, fevers, recent weight loss, headaches, or paresthesias. Any or all of these symptoms may accompany hematologic disease. The single most common symptom of anemia is fatigue. Clients are asked about feeling tired, needing more rest, or losing endurance during normal activities. They are asked to compare the extent and intensity of their activities during the past month with those of the same month a year ago. The nurse asks about other symptoms associated with anemia, such as vertigo, tinnitus, anorexia, dysphagia, and a sore tongue.
Physical Assessment The nurse performs a comprehensive physical assessment, because hematologic dysfunction affects the whole body. Certain problems are specific for hematologic assessment in older clients (see Chart 39-1).
SKIN ASSESSMENT The nurse inspects the color of the skin for pallor or jaundice and of the mucous membranes and nail beds for pallor or cyanosis. Pallor of the gums, conjunctivae, and palmar creases indicates decreased hemoglobin levels. The gums are also assessed for active bleeding in response to light pressure or brushing the teeth with a soft-bristled brush, and any lesions or draining areas are noted. The nurse assesses for signs of bleeding in the form of petechiae and large bruises (ecchymoses). Petechiae are pinpoint hemorrhagic lesions in the skin. Bruises may be confluent or clustered. For hospitalized clients, the nurse determines if there is bleeding from sites such as nasogastric tubes, endotracheal tubes, central lines, peripheral intravenous sites, or Foley catheters. Skin turgor and itching are noted, because dry skin or intense itching can indicate hematologic disease.
HEAD AND NECK ASSESSMENT The nurse notes pallor or ulceration of the oral mucosa. The tongue may be completely smooth in pernicious anemia and iron deficiency anemia or smooth and red iutritional deficiencies. These manifestations may be accompanied by fissures at the corners of the mouth. The nurse also observes for jaundice of the sclera. All lymph node areas are inspected and palpated. Any lymph node enlargement is documented, including whether palpation of the enlarged node causes pain. It is important to determine whether the enlarged node moves or remains fixed with palpation.
RESPIRATORY ASSESSMENT The rate and depth of respiration are assessed while the client is at rest, as well as during and after mild physical activity (e.g., walking 20 steps in 10 seconds). The nurse notes whether the client can complete a 10-word sentence without stopping for a breath. The nurse assesses whether the client is fatigued easily, experiences shortness of breath at rest or on exertion, or requires additional pillows to sleep comfortably at night. Many anemias cause these symptoms.
CARDIOVASCULAR ASSESSMENT The nurse observes for heaves, distended neck veins, edema, or signs of phlebitis. He or she also auscultates for murmurs, gallops, irregular rhythms, and abnormal blood pressure. Systolic blood pressure tends to be lower thaormal in clients with anemia. In conditions of hypercellularity, blood pressure is greater thaormal. Severe anemias can cause right-sided ventricular hypertrophy and heart disease.
RENAL AND URINARY ASSESSMENT The kidneys are extremely vascular, and bleeding problems may manifest as overt or occult hematuria (blood in the urine). The nurse inspects a voided sample of urine for color. Hematuria may be detected by grossly, bloody red or dark, brownish gold urine. The urine is tested for proteins with a urine test dipstick because hematologic problems may increase the protein content of urine. The urine sample also is tested for occult blood (Hemoccult test).
MUSCULOSKELETAL ASSESSMENT Rib or sternal tenderness is an important sign of hematologic malignancy. The nurse examines the superficial surfaces of all bones, including the ribs and sternum, by applying intermittent firm pressure with the fingertips. The client’s range of joint motion is assessed, and any swelling or joint pain is documented.
ABDOMINAL ASSESSMENT The normal adult spleen is usually not palpable. An enlarged spleen is associated with many hematologic problems. An enlarged spleen may be detected by percussion, but palpation is more reliable. The spleen lies just beneath the abdominal wall and is identified by its movement during respiration. During palpation, the client lies in a relaxed, supine position while the nurse stands on the client’s right side and palpates the left upper quadrant. The nurse palpates gently and cautiously, because an enlarged spleen may be tender and easily ruptured. Palpating the edge of the liver in the right upper quadrant of the abdomen can detect hepatic enlargement, which is often associated with hematologic problems. A normal liver may be palpable as much as 4 to
CENTRAL NERVOUS SYSTEM ASSESSMENT A thorough examination of the cranial nerves and neurologic function is necessary in many clients with hematologic disease. Vitamin B12 deficiency impairs cerebral, olfactory, spinal cord, and peripheral nerve function, and severe chronic deficiency may lead to irreversible neurologic degeneration. Many neurologic problems may develop in clients who have hematologic malignancies as a consequence of bleeding, infection, or tumor spread. When the client has a known or suspected bleeding disorder and has experienced any head trauma, the nurse expands the physical assessment to include frequent neurologic checks and mental status examinations. Other important clinical manifestations associated with impaired hematologic function include fever, chills, and night sweats.
Psychosocial Assessment The person with hematologic abnormalities may have a chronic illness (e.g., hemophilia or cancer) or an acute exacerbation of a chronic disease (e.g., pernicious anemia). In either instance each person brings his or her own coping style to the illness. After developing a rapport with the client, the nurse can learn what coping mechanisms he or she has used successfully during past illness or crises. The nurse also asks the client and family members about social support networks, community resources, and financial health. A problem in any of these areas can interfere with compliance with therapy and, ultimately, recovery.
Diagnostic Assessment
LABORATORY TESTS In hematologic disease, the most definitive signs are often the laboratory test results. Chart 39-3 lists laboratory data associated with hematologic function.
Tests of Cell Number and Function
COMPLETE BLOOD COUNT A complete blood count (CBC) includes a number of studies: red blood cell (RBC) count, white blood cell (WBC) count, hematocrit, and hemoglobin level. The RBC count measures circulating RBCs in 1 mm3 of venous blood, and the WBC count measures all leukocytes present in 1 mm3 of venous blood. To determine the percentages of different types of leukocytes circulating in the blood, a WBC count with differential leukocyte count is performed (see Chapter 20). The hematocrit (Hct) is calculated as the percentage of RBCs in the total blood volume, and the hemoglobin level represents the total amount of hemoglobin in the peripheral blood. The CBC can measure other variables of the circulating cells, including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). MCV measures the average volume or size of a single RBC and is useful for classifying anemias. When MCV is elevated, the cell is said to be abnormally large (macrocytic), as seen in megaloblastic anemias. When MCV is decreased, the cell is abnormally small (microcytic), as seen in iron deficiency anemia. MCH is the average amount of hemoglobin in a single RBC. MCHC measures the average concentration of hemoglobin in a single RBC. When the MCHC is decreased, the cell has a hemoglobin deficiency and is hypochromic, as in iron deficiency anemia.
RETICULOCYTE COUNT Another hematologic test helpful in determining bone marrow function is the reticulocyte count. A reticulocyte is an immature RBC. An elevated reticulocyte count indicates increased RBC production by the bone marrow. Normally about 2% of circulating RBCs are reticulocytes. An elevated reticulocyte count is desirable in an anemic client or after hemorrhage, because this indicates that the bone marrow is responding appropriately to a decrease in the total RBC mass. An elevated reticulocyte count without a precipitating cause may indicate a pathologic condition, such as polycythemia vera.
HEMOGLOBIN ELECTROPHORESIS Hemoglobin electrophoresis detects abnormal forms of hemoglobin, such as hemoglobin S in sickle cell disease. Hemoglobin A is the major component of hemoglobin in the normal RBC. Decreased levels of hemoglobin A with increasing levels of other types of hemoglobin are typical of some hematologic problems, such as sickle cell disease.
LEUKOCYTE ALKALINE PHOSPHATASE Leukocyte alkaline phosphatase (LAP) is an enzyme produced by normal mature neutrophils. Elevated LAP levels occur during episodes of infection or stress. An elevated neutrophil count without an accompanying elevation in LAP level is associated with chronic myelogenous leukemia.
COOMBS’ TEST The two Coombs’ tests (direct and indirect) are used for blood typing. The direct test detects the presence of antibodies (also called antiglobulins) against RBCs that may be attached to the RBCs. Although healthy people can make these antibodies, certain diseases (e.g., systemic lupus erythematosus, mononucleosis, and lymphomas) are associated with the production of antibodies directed against the body’s own RBCs. The presence of these antibodies usually causes a hemolytic anemia. The indirect Coombs’ test detects the presence of circulating antiglobulins. The test is used to determine whether the client has serum antibodies to the type of RBCs he or she is about to receive by blood transfusion.
SERUM FERRITIN, TRANSFERRIN, AND TOTAL IRON-BINDING CAPACITY Serum ferritin, transferrin, and total iron-binding capacity (TIBC) tests measure iron levels. Abnormal levels of iron and TIBC are associated with many hematologic problems, including iron deficiency anemia. The serum ferritin test measures the quantity of iron present as free iron in the plasma. The amount of serum ferritin is proportionally related to the amount of intracellular iron and represents 1% of the total body iron stores. Therefore the serum ferritin level provides a means to assess total iron stores. People with serum ferritin levels within
CAPILLARY FRAGILITY TEST The capillary fragility test, or Rumpel-Leede test, measures vascular hemostatic function by increasing intracapillary pressure in the arm. This is done by occluding venous outflow or by applying controlled negative pressure to a skin area. A blood pressure cuff is usually inflated to a pressure halfway between the systolic and diastolic pressures. This pressure is maintained for 5 minutes, and the petechiae that appear distal to the cuff are counted. Normally, five to ten petechiae appear. The capillary fragility test can help determine whether excessive bleeding or bruising results from increased capillary fragility or impaired platelet action.
BLEEDING TIME TEST The bleeding time test evaluates vascular and platelet activity during hemostasis. A special spring-loaded lancet that ensures uniform wound depth is used to make a small incision in the forearm while a blood pressure cuff remains inflated at
PROTHROMBIN TIME Prothrombin time (PT) is a measurement of how long blood takes to clot. This test reflects how much of the clotting factors II, V, VII, and X is present and how well they are functioning. When sufficient amounts of these clotting factors are present and functioning, the PT shows blood clotting between 11 and 13 seconds, or within 85% to 100% of the time needed for a control sample of blood to clot. PT is prolonged when one or more clotting factors is deficient, or when liver disease is present. Sodium warfarin (Coumadin, Warfilone’+O therapy is also monitored using PT levels. Appropriate warfarin therapy prolongs PT by 1.5 to 2 times the client’s normal PT value. Facilities are using the PT test less often to assess blood clotting because control blood is taken from different people and may not be the same from one day to the next, even in a single laboratory. To eliminate PT errors resulting from variations in control blood or in some of the chemicals used in the test, the International Normalized Ratio (INR) is used more often to assess clotting time.
INTERNATIONAL NORMALIZED RATIO The INR measures the same process as the PT but in a slightly different way—by establishing a normal mean or standard for PT. The INR is calculated by dividing the client’s PT by the established standard PT. A normal INR ranges between 0.7 and 1.8. When using the INR to monitor warfarin therapy, it should be maintained between 2.0 and 3.0 regardless of the actual PT in seconds.
PARTIAL THROMBOPLASTIN TIME Partial thromboplastin time (PTT) assesses the intrinsic coagulation cascade and evaluates the presence of factors II, V, VIII, IX, XI, and XII. PTT is prolonged whenever any of these factors is deficient, such as in hemophilia or disseminated intravascular coagulation (DIC). Because factors II, IX, and X are vitamin K dependent and are produced in the liver, liver disease can decrease their concentration and prolong PTT. Heparin (Calciparine, Liquaemin, Hepalean^) therapy is monitored by PTT. The desired ranges for therapeutic anticoagulation are 1.5 to 2.5 times the normal values. Controversy exists regarding whether this test is accurate when the blood sample is obtained through an existing vascular access device (e.g., arterial line or normal saline lock) instead of through a separate new venipuncture. Clinical studies have shown that with an appropriate discard, samples obtained through existing vascular access devices do accurately reflect the client’s activated partial thromboplastin time (see the Evidence-Based Practice for Nursing box at right).
PLATELET AGGLUTINATION/AGGREGATION Platelet aggregation, or the ability to clump, can be tested by mixing the client’s plasma with a substance called ristocetin. The degree of aggregation is noted. Aggregation can be impaired in von Willebrand’s disease and during the use of drugs such as aspirin, anti-inflammatory agents, and psychotropic agents. 1
RADIOGRAPHIC EXAMINATIONS
Assessment of the client with a suspected hematologic abnormality can include radioisotopic imaging. Isotopes are used to evaluate the bone marrow for sites of active blood cell formation and sites of iron storage. Radioactive colloids are routinely used to determine organ size and liver and spleen function. The client is given a radioactive isotope intravenously approximately 3 hours before the procedure. The client is taken to the nuclear medicine department for the scan, where he or she must lie still for approximately 1 hour. No special client preparation or follow-up care is needed for these tests. Standard x-ray studies may be used to diagnose certain hematologic disorders. For example, multiple myeloma causes characteristic bone destruction, with a “Swiss cheese” appearance on the x-ray film.
BONE MARROW ASPIRATION AND BIOPSY
A bone marrow aspiration or biopsy is often performed to evaluate the client’s hematologic status when other tests show persistent abnormal findings. Results can provide important information about bone marrow function, including the production of red blood cells (RBCs), white blood cells (WBCs), and platelets. Bone marrow aspiration and bone marrow biopsy are similar invasive procedures. In a bone marrow aspiration, cells and fluids are suctioned from the bone marrow. In a bone marrow biopsy, solid tissue and cells are obtained by coring out an area of bone marrow with a large-bore needle. A physician’s order and a signed, informed consent are obtained from the client before a bone marrow aspiration or biopsy is performed. Bone marrow aspiration may be performed by a physician, sanctioned clinical nurse specialist, nurse practitioner, or physician assistant, depending on the agency’s policy and regional law. The procedure may be performed at the client’s bedside, in an examination room, in a laboratory, or in a clinic setting. On learning what specific tests will be performed on the marrow, the nurse checks the facility’s procedure manual and checks with the hematology laboratory to determine how to handle the specimen. Some tests require the addition of heparin or other special solutions to the specimen.
CLIENT PREPARATION. Most clients experience anxiety or fear before a bone marrow aspiration. Clients who have experienced a bone marrow aspiration may have less anxiety or more anxiety depending on their previous experience. The nurse can help reduce anxiety and allay fears by providing accurate information and continuous emotional support. Some clients like to have their hand held during the procedure; other clients may want the nurse to hug or hold their entire upper body. The nurse explains the procedure to the client and says that he or she will stay during the entire procedure. Occasionally, a friend or family member is permitted to be pres ent to hold the client’s hand and provide additional emotional support. If a local anesthetic is used, the nurse explains that the injection will feel like a stinging or burning sensation. The nurse tells the client to expect a heavy sensation of pressure and pushing while the needle is being inserted. Some clients also can hear a crunching sound or feel a scraping sensation as the needle punctures the bone. The nurse explains that a brief sensation of painful pulling will be experienced as the marrow is aspirated by mild suction in the syringe. If a biopsy is performed, the client may feel more pressure and discomfort as the needle is rotated into the bone. The client is assisted onto an examining table, and the site (most commonly the iliac crest) is exposed. If this site is not available or if more marrow is needed, the sternum can be used. If the iliac crest is being used, the client is usually placed in the prone position or occasionally in the side-lying position. Depending on the tests to be performed on the specimen, a laboratory technician may also be present to ensure appropriate handling of the specimen.
PROCEDURE. The procedure usually lasts from 5 to 15 minutes. Clients may be uncomfortable and may experience pain. The type and amount of anesthesia or sedation used depends on the physician’s preference, the client’s preference and previous experience with bone marrow aspiration and biopsy, and the setting. A local anesthetic solution may be injected into the skin around the site. The client may also receive a mild tranquilizer or a rapid-acting sedative, such as midazolam hydrochloride (Versed) or lorazepam (Ativan, Apo-Lorazepam+, Novo-Lorazem). Some clients do well with guided imagery or autohypnosis. Aspiration or biopsy procedures are invasive, and sterile precautions are observed. The skin over the site is cleaned with a disinfectant solution. For an aspiration, the needle is inserted with a twisting motion, and the marrow is aspirated by pulling back on the plunger of the syringe. When sufficient marrow has been aspirated to ensure accurate analysis, the needle is carefully and rapidly withdrawn while the tissues are supported at the site. For a biopsy, a small skin incision is made, and the biopsy needle is inserted through the skin opening. Pressure and several twisting motions are performed to ensure coring and loosening of an adequate amount of marrow tissue. External pressure is applied to the site until hemostasis is ensured. A pressure dressing or sandbags may be applied to minimize bleeding at the site.
FOLLOW-UP CARE. The site is covered with a dressing after hemostasis is achieved and is observed closely for 24 hours for signs of bleeding and infection. A mild analgesic (aspirin-free) is prescribed for discomfort, and ice packs are applied over the site to limit bruising. The nurse instructs the client to inspect the site every 2 hours for the first 24 hours and to note the presence of active bleeding or bruising. The client is advised to avoid contact sports or any activity that might result in trauma to the site for 48 hours. Information obtained from bone marrow aspiration or biopsy reflects the degree and quality of bone marrow activity. The counts made on a marrow specimen can indicate whether stem cells, blast cells, committed cells, and more mature cell forms are present in the expected quantities and proportions. In addition, bone marrow aspiration or biopsy can confirm the spread of cancer cells from other tumor sites.
Disorders of the hematologic system can occur as a result of problems in the production, function, or normal destruction of any type of blood cell. The type and severity of the specific disorder determine the degree of threat to the client’s wellbeing. This chapter discusses hematologic conditions that may have only a minor impact on activities of daily living (ADLs), as well as those disorders that are potentially life threatening, such as sickle cell disease and leukemia.
The major cellular population of the blood consists of red blood cells (RBCs), or erythrocytes. Adequate tissue oxygenation depends on maintaining the circulating number of RBCs within the normal range for the person’s age and gender and ensuring that the cells can perform their normal functions. RBC disorders include problems in production, function, and destruction. These problems may result in an insufficient number or insufficient function of RBCs (anemia) or an excess of RBCs (polycythemia).
Anemia is a reduction in either the number of RBCs, the quantity of hemoglobin, or the hematocrit (percentage of packed RBCs per deciliter of blood). Anemia is a clinical sign, not a diagnosis, because it is a manifestation of a number of abnormal conditions. Anemia can result from dietary deficiencies, hereditary disorders, bone marrow disease, or bleeding. There are many types and causes of anemia. Some anemias are caused by a deficiency in one or more of the components needed to make fully functional RBCs. Such anemias can be caused by deficiencies of iron, vitamin B12, folic acid, or intrinsic factor. Additional causes include a decreased rate of erythrocyte production and increased destruction of RBCs. Table 40-1 lists common causes of various types of anemia.
Despite the many causes of anemia, the effects of anemia on the client (Chart 40-1) and the corresponding nursing care are similar for all types of anemia.
ANEMIAS RESULTING FROM INCREASED DESTRUCTION OF RED BLOOD CELLS
Sickle Cell Disease
OVERVIEW Sickle cell disease is a condition in which chronic anemia is one of many problems causing pain, disability, increased risk for disease, and early death. Once considered a childhood disorder, clients with sickle cell disease who receive appropriate supportive care may live into their 30s and 40s. In addition, there is great variation among clients in the severity of the disease and the onset of complications. r Pathophysiology The primary problem in this hereditary disorder is the formation of abnormal beta chains in the hemoglobin molecule. The hemoglobin molecule of adults is composed partially of the globin protein, consisting of two alpha chains and two beta chains of amino acids. This normal adult hemoglobin is called hemoglobin A (HbA).
The total hemoglobin of normal healthy adults is usually 98% to 99% HbA, with a small percentage of a fetal form of hemoglobin (HbF). In sickle cell disease, at least 40% of the total hemoglobin contains an abnormality of the beta chains, known as hemoglobin S (HbS). HbS is sensitive to changes in the oxygen content of the RBC. When RBCs containing large amounts of HbS are exposed to conditions of decreased oxygen, the abnormal beta chains contract and pile together within the cell, distorting the overall shape of the RBC. These cells assume a sickle shape, become rigid, clump together, and form clusters that block capillary blood flow (Figure 40-1).
Capillary obstruction leads to further tissue hypoxia (reduced oxygen supply) and more sickling, causing blood vessel obstructions and infarctions in the locally affected tissues. Situations that lead to sickling include hypoxia, dehydration, infections, vascular stasis, low environmental or body temperatures, acidosis, strenuous exercise, and anesthesia. Usually, sickled cells resume a normal shape when the precipitating condition is removed and proper oxygenation occurs. However, although the outward appearance of the RBCs is normal, at least some of the hemoglobin remains twisted, decreasing cell flexibility. The membranes of the cells become damaged over time, and cells become irreversibly sickled. In addition, the membranes of cells with HbS are more fragile and more easily destroyed in the spleen and in other organs that have long, twisted capillary pathways. The average life span of an RBC containing 40% or more of HbS is approximately 20 days, considerably less than the 120-day life span of RBCs containing only HbA.
This reduced life span is responsible for hemolytic (blood cell-destroying) anemia in clients with sickle cell disease. The client with sickle cell disease experiences periodic episodes of extensive cellular sickling, or crises. The crises have a sudden onset and can occur as frequently as weekly or as seldom as once a year. Many clients are in good health much of the time, with crises occurring sporadically in response to precipitating conditions that stimulate local or systemic hypoxemia (deficient oxygen in the blood). Repeated occlusions of progressively larger blood vessels have long-term negative effects on tissues and organs (Chart 40-2).
Most effects are thought to occur as a result of capillary and blood vessel occlusion leading to tissue hypoxia, anoxia, ischemia, and cell death. Tissues and organs begin to have small infarcted areas that eventually destroy all healthy cells and lead to organ failure. Tissues and organs most commonly affected in this way are the spleen, liver, heart, kidney, brain, bones, and retina.
Etiology Sickle cell disease is a genetic disorder with an autosomal recessive pattern of inheritance. The formation of the beta chains of the hemoglobin molecule is dependent on a pair of genes. A mutation in these genes leads to the formation of HbS instead of HbA.
When the client inherits one abnormal gene of this pair, the condition is called sickle cell trait. The client can pass the condition on to his or her children, but the client has only mild manifestations of the disease under severe precipitating conditions because less than about 30% of the hemoglobin is abnormal. When the client inherits two abnormal genes, the condition is called sickle cell disease (formerly sickle cell anemia), and the client has severe manifestations of the disease even under relatively mild precipitating conditions. In addition, if the client has children, each child will inherit one of the two abnormal genes and at least have sickle cell trait.
Incidence/Prevalence Sickle cell trait and different forms of sickle cell disease occur in people of all races and ethnicities but less often among Caucasians.
COLLABORATIVE MANAGEMENT
Assessment
HISTORY An adult with sickle cell disease has a long-standing diagnosis of the disorder. An adult who has sickle cell trait, however, may have had such mild clinical manifestations that he or she is unaware of the problem until it is diagnosed with an accompanying disorder or when anesthesia is administered. The nurse asks the client about previous crises, including precipitating events, severity, and usual treatments. Recent activities and situations are explored to determine the probable precipitating condition or event. The nurse also reviews all activities and events during the previous 24 hours, including food and fluid intake, exposure to temperature extremes, types of clothing worn, medications taken, exercise, trauma, stress, and ingestion of alcohol or other recreational drugs. This activity review provides important information about fatigue, activity tolerance, and participation in activities of daily living (ADLs). The client is asked about changes in sleep and rest patterns, ability to climb stairs, and any activity that induces shortness of breath. Obtaining a subjective baseline assessment of the client’s perceived energy level using a scale ranging from 0 to 10 (0 = not tired with plenty of energy; 10 = total exhaustion) can be useful in evaluating the degree of fatigue and the effectiveness of later treatments.
PHYSICAL ASSESSMENT/CLINICAL MANIFESTATIONS Pain is the most common symptom experienced during sickle cell crisis. Jaundice may also be present as a result of increased red blood cell (RBC) destruction and release of bilirubin. Other clinical manifestations vary with the site of tissue damage.
CARDIOVASCULAR ASSESSMENT. The nurse assesses the client’s cardiovascular and peripheral vascular status by comparing peripheral pulses, temperature, and capillary refill in all extremities. Extremities distal to blood vessel occlusion are cool to the touch with slow capillary refill and may have diminished or absent pulses. The heart rate may be rapid and the blood pressure low to average, with a decreased pulse pressure because breakage of RBCs leads to anemia.
INTEGUMENTARY ASSESSMENT. The skin may be pale or cyanotic as a result of decreased perfusion and anemia. The nurse examines the lips, tongue, nail beds, conjunctivae, palms, and soles at regular intervals for subtle color changes. With cyanosis, the lips and tongue are gray, and the palms, soles, conjunctivae, and nail beds have a bluish tinge. Another skin manifestation associated with sickle cell disease is jaundice. Bilirubin, a major component of RBCs, is released when fragile cells are damaged, leading to jaundice.
The nurse assesses for jaundice in clients with darker skin by inspecting the oral mucosa, especially the hard palate, for yellow discoloration. Inspection of the conjunctivae and adjacent sclera may be misleading because of normal deposits of subconjunctival fat that produce a yellowish hue when seen in contrast to the dark periorbital skin. Therefore the nurse examines the sclera closest to the cornea to diagnose jaundice more accurately. Similarly, the palms and soles of darkskinned clients may appear yellow if callused and should not be mistaken for jaundice. Jaundice from excessive bilirubin may also cause intense itching. In spite of the anemia, clients with sickle cell disease usually are not deficient in iron. In fact, with increased RBC production and destruction, iron released from the cells may increase the pigmentation of the skin. As many as 75% of adult clients with sickle cell disease have stasis ulcers or pressure ulcers on the lower extremities. The ulcers usually occur on the lower portion of the legs (Rausch & Pollard, 1998). The outer sides and inner aspect of the ankle or the shin are common sites. The nurse inspects the legs and feet for open lesions or darkened areas that may indicate necrotic tissue. Infections of these lesions occur frequently.
ABDOMINAL ASSESSMENT. Abdominal organs are usually the first to be damaged as a result of multiple episodes of hypoxia and ischemia. The nurse inspects the abdomen for asymmetry or bulging areas, gently palpating it. Affected organs, such as the liver or spleen, may be firm and enlarged with a nodular texture in later stages of the disease.
MUSCULOSKELETAL ASSESSMENT. Extremities are a common site of vascular occlusion among clients who have sickle cell disease. In addition, joints may be damaged from frequent hypoxic episodes and undergo necrotic degeneration. The nurse inspects the extremities for symmetry and records any areas of swelling or color difference. Clients are asked to move all joints, and the nurse notes the range of motion and any accompanying pain.
CENTRAL NERVOUS SYSTEM ASSESSMENT. Changes in central nervous system (CNS) function may occur directly or indirectly in sickle cell disease. During crises, clients may have a low-grade fever. If the CNS sustains infarcts or repeated episodes of hypoxia, they may have seizure activity or clinical manifestations of a stroke. Hand grasps are assessed bilaterally. The nurse assesses gait and coordination in those clients who are permitted to walk.
PSYCHOSOCIAL ASSESSMENT Psychosocial assessment is important because behavioral changes may be the first observable clinical manifestations of cerebral hypoxia. The nurse observes the client and documents presenting behavior. Family members or significant others are questioned to determine whether the presenting behavior and mental status are typical. Sickle cell disease represents a chronic, painful, life-limiting disorder that can be passed on to one’s children. The nurse assesses the client’s psychosocial needs in terms of new factors, established support systems, previous and current coping patterns, and disease progression. The client is asked how he or she views the disease and what adjustments in lifestyle have been made to accommodate limitations.
LABORATORY ASSESSMENT The primary laboratory finding associated with sickle cell disease is the large percentage of hemoglobin S (HbS) present on electrophoresis. A person who has sickle cell trait usually expresses less than 40% HbS, and the client with sickle cell disease may express 85% to 95% HbS. This percentage does not change during crises. Another indicator of sickle cell disease is the percentage of RBCs showing irreversible sickling. This value is less than 1% among people who do not have sickle cell disease, is 5% to 50% among people with sickle cell trait, and may exceed 90% among clients with sickle cell disease.
A variety of other laboratory tests reflect the problems associated with sickle cell disease, especially during crises. The hematocrit of clients with sickle cell disease is usually low (between 20% and 30%). This value decreases even more dramatically during vascular occlusive crises, or aplastic crises, when the bone marrow temporarily fails to produce cells during stressful periods (such as infection). The reticulocyte count is elevated, indicating anemia of long duration. Often the mean corpuscular hemoglobin concentration (MCHC) and total bilirubin level are elevated in the client who has sickle cell disease. The total white blood cell (WBC) count is usually above normal among clients who have sickle cell disease. It is thought that this elevation is related to chronic inflammation resulting from tissue hypoxia and ischemia.
RADIOGRAPHIC ASSESSMENT Bone changes occur as a result of chronically stimulated marrow and hypoxic bone tissue. The skull may show radiographic changes resulting from chronic bone surface resorption and regeneration, giving the skull a “crew cut” appearance. Joint necrosis and degeneration also are obvious on x-ray examination.
OTHER DIAGNOSTIC ASSESSMENT Electrocardiographic (ECG) changes document cardiac infarcts and tissue damage. Specific ECG changes are related to the area of the myocardium sustaining the damage. Ultrasonography, computed tomography (CT), positron emission tomography (PET), and magnetic resonance imaging (MRI) may reveal soft-tissue and organ degenerative changes resulting from inadequate oxygenation and chronic inflammation. Interventions The most common health problems for the client with sickle cell disease are pain, the potential complications of sepsis, and multiple organ dysfunction. Interventions are aimed at reducing or preventing these problems.
PAIN. The most prominent clinical manifestation of sickle cell disease is pain. More than one fifth of clients experience frequent painful episodes and may have as many as 40 episodes per year (Rausch & Pollard, 1998). The pain associated with sickle cell crisis is the result of ischemic tissue injury caused by obstructed blood flow. The pain is often severe enough to require hospitalization and large doses of opioid analgesics. Pain is chronic with acute episodes and can occur anywhere in the body, often where circulation is impaired. It is sudden and is often described as gnawing or throbbing. Subjective reports of pain may be the only evidence, because the chronic nature of the pain may make physiologic changes less obvious. The subjective nature of the pain, racial prejudice, and concern for addiction often cause the client with sickle cell disease to be labeled as difficult (Gorman, 1999).
Health care providers must be aware of their own attitudes when caring for this population and must realize that lack of knowledge, in addition to concern for addiction, often prevents proper pain management of clients with sickle cell disease. Use of a pain rating scale by all nursing personnel can promote proper pain management. The nurse asks the client to rate pain on a scale ranging from 0 to 10 and evaluates the effectiveness of interventions based on the ratings. Use of contracts for pain control can also be helpful.
DRUG THERAPY. Clients in acute sickle cell crisis often require at least 48 hours of parenteral analgesics. (Chart 40-3 highlights best practices for nursing care of the client in sickle cell crisis.)
Morphine and hydromorphone (Dilaudid) are the medications of choice (Gorman, 1999). For sickle cell crisis, these agents should be administered intravenously on a routine schedule. Once relief is obtained, the intravenous (IV) dose can be tapered and then administered orally (Rausch & Pollard, 1998). Meperidine (Demerol) is also used for sickle cell crisis, but long-term use of this agent can cause neurologic symptoms, including anxiety and seizures (Gorman, 1999). “As needed” (prn) schedules are discouraged because they do not provide adequate relief, and intramuscular (IM) injections are avoided because frequent injections lead to sclerosing of tissue (and absorption may be impaired by poor circulation). Moderate pain may be treated with oral doses of codeine, morphine sulfate, or nonsteroidal anti-inflammatory drugs (NSAIDs).
COMPLEMENTARY AND ALTERNATIVE THERAPIES. Complementary therapies and other nonpharmacologic measures, such as keeping the room warm, using distraction and relaxation techniques, proper positioning with support for painful areas, aroma therapy, therapeutic touch, and warm soaks or compresses, have all been useful in decreasing pain. The nurse must not assume, however, that these methods alone will provide adequate pain relief. Analgesics are required to treat sickle cell pain.
POTENTIAL FOR SEPSIS. The client with sickle cell disease is more susceptible to bloodborne infections and infection by encapsulated microorganisms, such as Streptococcus pneumoniae and Haemophilus influenzae, as a result of decreased spleen function. Interventions aim at preventing or halting the process of infection, controlling infection, and initiating early, effective treatment regimens for specific infections.
PREVENTION/EARLY DETECTION. A major objective is to protect the client in sickle cell crisis from infection. Frequent, thorough handwashing is of the utmost importance. Any person with an upper respiratory tract infection who must enter the client’s room wears a mask. Strict aseptic technique is used for all invasive procedures. The nurse continually assesses the client for the presence of infection and monitors a daily complete blood count (CBC) with differential WBC count. The oral mucosa is inspected during every nursing shift for lesions indicating fungal or viral infection. The lungs are auscultated every 8 hours for crackles, wheezes, or diminished breath sounds. Each time the client voids, assistive nursing personnel inspect the urine for odor and cloudiness, and the client is asked about any sensation of urgency, burning, or pain during urination. Vital signs are taken at least every 4 hours to assess for fever.
DRUG THERAPY. Drug therapy is a primary defense against the infections that develop in the client with sickle cell disease. Prophylactic therapy with twice-daily administration of oral penicillin in the penicillin-tolerant client has resulted in dramatic reductions in the number of pneumonia and other streptococcal infections. Yearly vaccination for influenza is advocated (Rausch & Pollard, 1998). Drug therapy for an actual infection can control infection and prevent complications associated with sepsis. Agents used depend on the sensitivity of the specific organism causing the infection, as well as the extent of the infection.
POTENTIAL FOR MULTIPLE ORGAN DYSFUNCTION.
The threat of multiple organ dysfunction arises from continued vascular occlusions after clumping of sickled cells. Management of sickle cell disease focuses on prevention of vascular occlusion and promotion of adequate oxygenation.
The client in sickle cell crisis is admitted to the acute care hospital. The nurse assesses for adequacy of circulation to all body areas. Restrictive clothing is removed, and the client is instructed to avoid keeping the hips or knees in a flexed position.
Dehydration perpetuates cell sickling and must be avoided. Nursing personnel assist the client in maintaining an adequate hydration status. The client in crisis requires an oral or parenteral intake of at least 200 mL/hr.
Oxygen is ordered, and the nurse ensures that oxygen therapy is delivered appropriately, including nebulization to prevent dehydration. Transfusion therapy has been used to decrease the incidence of organ dysfunction and stroke. RBC transfusions are therapeutic because levels of hemoglobin A (HbA) are sustained, whereas levels of hemoglobin S (HbS) are diluted. Transfusions also suppress erythropoiesis, thereby decreasing the production of sickle cells. Transfusions may be administered in either the acute care or clinic setting by a registered nurse. The nurse monitors the client closely for complications of transfusion therapy (discussed under Transfusion Reactions, p. 866).
In some treatment centers, bone marrow transplantation is being performed to correct abnormal hemoglobin permanently. Because bone marrow transplantation is expensive and may result in chronic and life-threatening complications, its risks and benefits need to be seriously considered for each client.
Community-Based Care Sickle cell disease is a progressive disorder with periods of varying degrees of exacerbation. Rarely is there a true remission, although crisis episodes may be infrequent. Care focuses on prevention of complications, an ongoing daily necessity for the client with sickle cell disease.
The client with sickle cell disease may be cared for in a variety of settings, including acute care, subacute care, extended or assistive care, and home care. The client is taught to avoid specific activities that lead to hypoxia and hypoxemia. Recognition of the early signs and symptoms of crisis is emphasized, so that appropriate treatment can be initiated early to prevent undue pain, complications, and permanent tissue damage. The client is often given opioid analgesics for self-management of sickle cell crises at home; the nurse teaches clients and families about the correct administration. In addition, clients are counseled about the hereditary aspects of sickle cell disease, and information concerning prenatal diagnosis, birth control methods, and pregnancy options is offered.
Glucose-6-Phosphate Dehydrogenase Deficiency Anemia
OVERVIEW Many forms of congenital hemolytic (blood cell-destroying) anemia result from defects or deficiencies of one or more enzymes within the red blood cell (RBC). More than 200 such disorders have been identified. Most of these enzymes are needed to complete some critical step in cellular energy production. The most common type of congenital hemolytic anemia is associated with a deficiency of the enzyme glucose-6- phosphate dehydrogenase (G6PD). This disease is inherited as an X-linked recessive disorder and affects about 10% of all African Americans (Cotran, Kumar, & Robbins, 1999).
G6PD stimulates critical reactions in the glycolytic pathway. RBCs contaio mitochondria (sites of high-efficiency production of the energy compound adenosine triphosphate [ATP]), so active glycolysis is essential for energy metabolism. Newly produced RBCs from clients with G6PD deficiency have relatively sufficient quantities of G6PD; however, as the cells age, the concentration diminishes drastically. Cells that have reduced amounts of G6PD are more susceptible to breaking during exposure to specific drugs (e.g., phenacetin, sulfonamides, aspirin [acetylsalicylic acid], quinine derivatives, thiazide diuretics, and vitamin K derivatives) and toxins.
After exposure to any of these agents, clients experience acute intravascular hemolysis lasting from 7 to 12 days. During this acute phase, anemia and jaundice develop. The hemolytic reaction is self-limited because only older erythrocytes, containing less G6PD, are destroyed.
COLLABORATIVE MANAGEMENT It is critical that the precipitating drug or the agent responsible for the hemolytic reaction be identified and totally removed. People should be screened for this deficiency before donating blood, because administration of cells deficient in G6PD can be hazardous for the recipient. During and immediately after an episode of hemolysis, adequate hydration is essential to prevent precipitation of cellular debris and hemoglobin in the kidney tubules, which can lead to acute tubular necrosis. Osmotic diuretics, such as mannitol (Osmitrol), may assist in preventing this complication. Transfusion therapy is indicated when anemia is present and kidney function is normal. Table 40-2 lists indications for transfusion with various types of blood components.
Immunohemolytic Anemia
OVERVIEW Increased RBC destruction through hemolysis can occur in response to many situations, including trauma, infection (especially malarial infections), and autoimmune reactions. All increase the rate at which RBCs are destroyed by causing lysis (breakage) of the RBC membrane. The most common types of hemolytic anemias in industrialized countries are the immunohemolytic anemias, also referred to as autoimmune hemolytic anemias (Cotran, Kumar, & Robbins, 1999).
In immunohemolytic anemia, immune system components attack a person’s own RBCs. The exact mechanism that causes immune components to no longer recognize blood cells as self and to initiate destructive processes against RBCs is not known. Some hemolytic anemias are present with other autoimmune disorders (such as systemic lupus erythematosus) or lymphoproliferative disorders. Regardless of the cause, RBCs are viewed as non-self by the immune system and are destroyed.
There are two types of immunohemolytic anemia: warm antibody anemia and cold antibody anemia. Warm antibody anemia is usually associated with immunoglobulin G (IgG) antibody excess. These antibodies are most active at 98° F (37° C) and may be stimulated by drugs, chemicals, or other autoimmune problems. Cold antibody anemia is associated with fixation of complement proteins on immunoglobulin M (IgM) and occurs best at 86° F (30° C). This problem is commonly associated with a Raynaud-like response in which the arteries in the distal extremities constrict profoundly in response to cold temperatures or stress.
COLLABORATIVE MANAGEMENT Treatment depends on clinical severity. Steroid therapy for mild to moderate immunosuppression is the first line of treatment and is temporarily effective in most clients. Splenectomy and more intensive immunosuppressive therapy with cyclophosphamide (Cytoxan, Procytox4>) and azathioprine (Imuran) may be instituted if steroid therapy fails. Plasma exchange therapy to remove attacking antibodies is effective for clients who do not respond to immunosuppressive therapy.
ANEMIAS RESULTING FROM DECREASED PRODUCTION OF RED BLOOD cells
Anemias associated with decreased red blood cell (RBC) production can result from alterations in any of a variety of physiologic mechanisms. Some anemias are caused by failure or inability of the bone marrow to properly produce RBCs; others are caused by failure of the body to make or absorb a specific component necessary for RBC production.
Iron Deficiency Anemia
OVERVIEW The adult body contains between 2 and
COLLABORATIVE MANAGEMENT
The primary treatment of clients with iron deficiency anemia is to increase the oral intake of iron from common food sources (Table 40-3).
An adequate diet supplies a person with about 10 to 15 mg of iron per day, of which only 5% to 10% is absorbed in the stomach, duodenum, and upper jejunum (Worrall, Tompkins, & Rust, 1999). This amount is sufficient to meet the needs of healthy men and healthy women after childbearing age but is not sufficient to supply the greater needs of menstruating women and adolescents during growth spurts. Fortunately, if iron intake is inadequate, or if bleeding or pregnancy occurs, the gastrointestinal tract is capable of increasing the absorption of iron to about 20% to 30% of the total daily intake (Cotran, Kumar, & Robbins, 1999). When iron deficiency anemia is severe, iron preparations can be administered intramuscularly. Such preparations are administered using the Z-track best practice method outlined in Chart 40-4.
Vitamin B12 Deficiency Anemia
OVERVIEW Proper production of RBCs depends on adequate deoxyribonucleic acid (DNA) synthesis in the precursor cells so that cell division and maturation into functional RBCs can occur. All DNA synthesis requires adequate amounts of folk acid (Mate) to ensure the availability of the nucleotide thymidine, which stimulates DNA synthesis. One function of vitamin B12 is to serve as a cofactor to activate the enzyme system responsible for transporting folic acid into the cell, where DNA synthesis occurs. Thus a deficiency of vitamin B12 indirectly causes anemia by inhibiting folic acid transportation and limiting DNA synthesis in RBC precursor cells. These precursor cells then undergo improper DNA synthesis and increase in size. Only a few are released from the bone marrow.
This type of anemia is called megaloblastic (macrocytic) because of the large size of these abnormal cells. Vitamin B12 deficiency can result from inadequate intake (dietary deficiency). This can occur with strict vegetarian diets or diets lacking sufficient dairy products. Conditions such as small bowel resection, diverticula, tapeworm, or overgrowth of intestinal bacteria can lead to poor absorption of vitamin B12 from the intestinal tract (Worrall, Tompkins, & Rust, 1999). Anemia caused by failure to absorb vitamin B12 (pernicious anemia) can also result from a deficiency of intrinsic factor (a substance normally secreted by the gastric mucosa), which is necessary for intestinal absorption of vitamin B12. Vitamin Bl2 deficiency anemia may be mild or severe, usually develops slowly, and produces few symptoms. Clients usually have pallor and jaundice, as well as glossitis (a smooth, beefy-red tongue), fatigue, and weight loss. Because vitamin B12 also is necessary for normal nervous system functioning, especially of the peripheral nerves, clients with pernicious anemia may also have neurologic abnormalities, such as paresthesias (abnormal sensations) in the feet and hands and disturbances of balance and gait (Chart 40-5).
COLLABORATIVE MANAGEMENT When anemia is caused by a dietary deficiency, the client must increase the intake of foods rich in vitamin B12 (animal proteins, eggs, dairy products). Vitamin supplements may be prescribed when anemia is severe. For clients who have anemia as a result of a deficiency of intrinsic factor, vitamin B12 must be administered parenterally on a regular schedule (usually weekly for initial treatment, then monthly for maintenance).
Folic Acid Deficiency Anemia
OVERVIEW Primary folic acid deficiency can also cause megaloblastic anemia. Clinical manifestations are similar to those of vitamin B 12 deficiency without the accompanying nervous system manifestations, because folic acid does not appear to affect nerve function. The absence of neurologic problems is an important diagnostic finding to differentiate folic acid deficiency from vitamin B12 deficiency. The disease develops slowly, and symptoms may be attributed to other problems or diseases. The three common causes of folic acid deficiency are poor nutrition, malabsorption, and drugs. Poor nutrition, especially a diet lacking green leafy vegetables, liver, yeast, citrus fruits, dried beans, and nuts, is the most common cause. Chronic alcohol abuse and parenteral alimentation without folic acid supplementation are other dietary causes. Malabsorption syndromes, such as Crohn’s disease, are the second most common cause. Specific drugs impede the absorption and conversion of folic acid to its active form and can also lead to folic acid deficiency and anemia. Such drugs include methotrexate, some anticonvulsants, and oral contraceptives.
COLLABORATIVE MANAGEMENT Prevention of folic acid deficiency anemia is aimed at identifying high-risk clients, such as older, debilitated clients with alcoholism; clients prone to malnutrition; and those with increased folic acid requirements. A diet high in folic acid and vitamin B12 prevents a deficiency (see Table 40-3). By routinely including assessment of dietary habits in a health history, the nurse can determine which clients are at risk for dietinduced anemias and provide appropriate follow-up. For the client diagnosed with this type of anemia, management includes oral folic acid 1 mg daily or intramuscular administration of folic acid for clients with absorption problems (Worrall, Tompkins, & Rust, 1999).
Aplastic Anemia
OVERVIEW Aplastic anemia is a deficiency of circulating erythrocytes resulting from arrested development of RBCs within the bone marrow. It is caused by an injury to the hematopoietic precursor cell, the pluripotent stem cell. Although aplastic anemia sometimes occurs alone, it is usually accompanied by agranulocytopenia (a reduction in leukocytes) and thrombocytopenia (a reduction in platelets). These three problems occur at the same time because the bone marrow produces not only RBCs but also white blood cells (WBCs) and platelets. Consequently, if the bone marrow is abnormal for any reason or if it has been exposed to a toxic substance that can damage bone marrow cells, production of erythrocytes, leukocytes, and thrombocytes slows greatly. Pancytopenia (a deficiency of all three cell types) is common in aplastic anemia. The onset of aplastic anemia may be insidious or rapid. The development of aplastic anemia, although relatively rare, is associated with chronic exposure to several toxic agents (see Table 39-4). In about 50% of cases, the cause of aplastic anemia is unknown. Aplastic anemia may occur as an aftermath of viral infection (Cotran, Kumar, & Robbins, 1999), but the mechanism of bone marrow damage is unknown.
COLLABORATIVE MANAGEMENT Blood transfusions are the mainstay of treatment for clients with aplastic anemia. Transfusion is indicated only when the anemia causes real disability or when bleeding is life threatening because of thrombocytopenia. Unnecessary transfusion, however, increases the opportunity for the development of immune reactions to platelets, shortens the life span of the transfused cell, and may increase the rate of rejection of transplanted marrow cells. Thus transfusions are discontinued as soon as the bone marrow begins to produce RBCs. Because clients with some types of aplastic anemia have a disease course similar to that of autoimmune problems, immunosuppressive therapy may be helpful.
Agents that selectively suppress lymphocyte activity, such as antilymphocyte globulin (ALG), antithymocyte globulin (ATG), and cyclosporine (Sandimmune), have brought about partial or complete remissions. In more severe cases, general immunosuppressive agents, such as prednisone and cyclophosphamide (Cytoxan, Procytox”*1), have been effective. Splenectomy (removal of the spleen) is considered in clients with an enlarged spleen that is either destroying normal RBCs or suppressing their development. Bone marrow transplantation, which replaces defective stem cells, has also resulted in a cure for some clients (Cotran, Kumar, & Robbins, 1999). Cost, availability, and complications limit this technique for treatment of aplastic anemia, however.
POLYCYTHEMIA
In polycythemia, the number of red blood cells (RBCs) in whole blood is greater thaormal. The blood of a client with polycythemia is hyperviscous (thicker thaormal blood). The problem may be temporary (occurring as a result of other conditions) or chronic. One type of polycythemia, polycythemia vera, is fatal if left untreated.
Polycythemia Vera
OVERVIEW Polycythemia vera (PV) is characterized by a sustained increase in blood hemoglobin concentration to 18 g/dL, an RBC count of 6 million/mm3, or a hematocrit increase to 55% or greater. PV is a cancer of the RBCs with three major hall marks: continuous production of massive numbers of RBCs, excessive leukocyte production, and overproduction of thrombocytes. As described in Chart 40-6, extreme hypercellularity (cell excess) of the peripheral blood occurs in people with PV.
The skin, especially facial, and mucous membranes have a dark, flushed (plethoric) appearance. These areas may appear purplish or cyanotic because the blood in these tissues is incompletely oxygenated. Most clients experience intense itching related to vasodilation and variation in tissue oxygenation. Blood viscosity is also greatly increased, causing a corresponding increase in peripheral resistance. Superficial veins are visibly distended. Blood moves more slowly through all tissues and thus places increased demands on the pumping action of the heart, resulting in hypertension. In some highly vascular areas, blood flow may become so slow that vascular stasis occurs. Vascular stasis causes thrombosis (clot formation) within the smaller vessels to the extent that the vessels are occluded and the surrounding tissues experience hypoxia, progressing to anoxia and further to infarction and necrosis. Tissues most prone to this complication are the heart, spleen, and kidneys, although infarction with loss of tissue and organ function can occur in any organ or tissue.
Because the actual number of cells in the blood is greatly increased and the cells are not completely normal, individual cell life spans are shorter. The shorter life spans, coupled with increased cell production, result in a rapid turnover of peripheral blood cells. This rapid turnover increases the amount of intracellular products (released when cells die) in the blood, adding to the general “sludging” of the blood. These products include uric acid and potassium, which cause the symptoms of gout and hyperkalemia (elevated serum potassium level). Later clinical manifestations of PV are related to abnormal blood cells. Even though the number of circulating erythrocytes is greatly increased, their oxygen-carrying capacity is impaired, and clients experience severe generalized hypoxia. In spite of the RBC excess, most clients with PV are susceptible to bleeding problems because of an associated platelet dysfunction (Cotran, Kumar, & Robbins, 1999).
COLLABORATIVE MANAGEMENT
Polycythemia vera is a malignant disease that progresses in severity over time. If left untreated, few people with PV live longer than 2 years. Conservative management with repeated phlebotomies (two to five times per week) can prolong life for 5 to 10 years. (Phlebotomy is the collection of the client’s RBCs to decrease the number of RBCs and diminish blood viscosity.) Maintaining adequate hydration and promoting venous return are essential to prevent thrombus formation. Therapy aims to prevent clot formation and includes the use of anticoagulants. Chart 40-7 lists preventive tips for clients with PV.
As the disease progresses, clients need more intensive therapies that suppress bone marrow activity, including oral alkylating agents and/or irradiation with injections of radioactive phosphorus. Bone marrow transplantation, an experimental treatment, is promising, but the results are too limited to determine its application to PV.
White Blood Cell Disorders: Acute Leukemias. Interventions For Clients With Acute Leukemias
Disorders of the hematologic system can occur as a result of problems in the production, function, or normal destruction of any type of blood cell. The type and severity of the specific disorder determine the degree of threat to the client’s wellbeing. This chapter discusses hematologic conditions that may have only a minor impact on activities of daily living (ADLs), as well as those disorders that are potentially life threatening, such as sickle cell disease and leukemia.
WHITE BLOOD CELL DISORDERS
As discussed in Chapter 20, white blood cells (WBCs), or leukocytes, provide protection from invading non-self cells and cancer cells in several ways. These protective functions depend on maintaining normal numbers and ratios of many specific mature, circulating leukocytes. When any one type of WBC is present in either abnormally high or abnormally low amounts, hematopoietic function and immune function may be altered to some degree, placing clients at risk for specific complications. This section covers the pathologic changes and nursing care requirements for clients with disorders involving overgrowth of specific types of WBCs.
LEUKEMIA
OVERVIEW The leukemias are a group of malignant disorders involving abnormal overproduction of a specific WBC type, usually at an immature stage, in the bone marrow. Leukemia may be acute, with a sudden onset and short duration, or chronic, with a slow onset and persistent symptoms over a period of years. Leukemias are categorized by the specific maturational pathway from which the abnormal cells arise (Dietz, 1999). Leukemias in which the abnormal cells arise from within the committed lymphoid maturational pathways are lymphocytic or lymphoblastic. Leukemias in which the abnormal cells arise within the committed myeloid maturational pathways are myelocytic or myelogenous. Several subtypes exist for each of these diseases, which are classified according to the degree of maturity of the abnormal cell and the specific cell type involved (Table 40-4).
Pathophysiology The basic problem in leukemia is a malignant transformation of the stem cells or early committed precursor leukocyte cells, causing an abnormal proliferation of a specific type of leukocyte. The functionally and structurally abnormal immature leukocytes, produced in excessive quantities in the bone marrow, essentially shut down normal bone marrow production of erythrocytes, platelets, and other mature leukocytes. This situation leads to anemia, thrombocytopenia, and leukopenia of the unaffected WBC types, even though the number of immature, abnormal WBCs in the circulation is greatly elevated (Dietz, 1999). Without treatment, the client usually dies of infection or hemorrhage. For clients with acute leukemias, these pathologic changes occur rapidly and, without intervention, progress quickly to death. Chronic leukemia may be present for many years before overt pathologic changes occur (Pittinger, 1999).
Etiology Epidemiologic studies suggest that many different genetic and environmental factors may be involved in the development of leukemia. Although only a few of these factors have been positively identified, the basic mechanism appears to involve gene damage of cells, changing those cells from a normal to a malignant (cancer) state. The following conditions or substances are possible risk factors: ionizing radiation, chemicals and drugs, marrow hypoplasia (slow functioning with less than the normal production rate of blood cells), environmental interactions, genetic factors, viral factors, immunologic factors, and the interaction of these factors (Dietz, 1999). Ionizing radiation exposure in large quantities appears to be a major risk factor. Exposures ranging from therapeutic irradiation (for such diseases as ankylosing spondylitis and Hodgkin’s lymphoma) to environmental irradiation (such as the atomic bomb at Hiroshima or the nuclear accident at Chernobyl) have been associated with leukemia. Chemicals and drugs have been linked to the development of leukemia.
Marrow hypoplasia can increase the risk of leukemia. A reduction or alteration in the production of hematopoietic cells may be responsible. Examples of conditions associated with the later development of leukemia include Fanconi’s syndrome, paroxysmal nocturnal hemoglobinuria during its aplastic phase, and myelodysplastic syndromes. Genetic factors are suspected as a cause of leukemia because of the increased frequency of leukemia in the following populations: identical twins of clients with leukemia, as well as people with Down syndrome, Bloom syndrome, Fanconi’s syndrome, and Klinefelter’s syndrome. Chromosomal aberration may be an important factor in these syndromes (Dietz, 1999). Immunologic factors, especially immune deficiencies, may also favor the development of leukemia. Leukemia among im- munodeficient people may be a result of immunosurveillance failure, or the pathologic mechanisms that cause the immune deficiency may also trigger cancer in the WBC population. Interaction of multiple host and environmental factors may result in leukemia. Because each person tolerates the interaction of these factors differently, it is difficult to determine the origin of any specific leukemia.
Incidence/Prevalence The leukemias account for 2% of all newly diagnosed cases of cancer and for 4% of all deaths from cancer (American Cancer Society, 2001). The incidence and the frequency of leukemia depend on many factors, including the type of WBC affected, age, gender, race, and geographic locale. In the United States an estimated 28,800 new cases of leukemia were projected for 2001 (American Cancer Society, 2000).
In this country, leukemia is categorized into any one of four basic types based on the cell type affected and the rate of progression of the leukemia:
• Acute myelogenous leukemia (AML) occurs with similar frequency in all ages and is the most common form of leukemia in adults.
• Acute lymphocytic leukemia (ALL) constitutes about 10% of adult leukemias but is most common in children.
• Chronic myelogenous leukemia (CML) constitutes about 20% of adult leukemias, occurring more often in people older than 50 years of age.
• Chronic lymphocytic leukemia (CLL) is the rarest type of leukemia, occurring primarily in people older than 50 years of age. Characteristics and risk factors associated with these four types of leukemia are presented in Table 40-4.
COLLABORATIVE MANAGEMENT
Assessment
HISTORY The nurse asks the client about risk factors and causative factors. Age is important because the incidence of adult leukemia increases with age. Occupation and hobbies may also reveal specific environmental exposures that increase the risk of leukemia. Previous illnesses and the medical history may indicate exposure to ionizing radiation or medications that increase risk. Because of leukemia-related alterations of immune function, the risk for infection is increased in the client with leukemia. The nurse asks about the frequency and severity of infectious processes (such as colds, influenza, pneumonia, bronchitis, or unexplained episodes of fever) during the preceding 6 months (Pittinger, 1999).
Because platelet function may be diminished in people with leukemia, the client is asked about any overt or hidden excessive bleeding episodes, such as the following:
• A tendency to bruise easily
• Nosebleeds
• Increased menstrual flow
• Bleeding from the gums
• Rectal bleeding
• Hematuria (blood in the urine)
• Prolonged bleeding after minor abrasions or lacerations
If the client has experienced such an episode, the nurse asks whether this type and extent of bleeding constitute the usual response to injury or represent a change. The client with leukemia often experiences weakness and fatigue resulting from anemia and increased metabolic and energy demands of the leukemic cells.
The client is asked whether he or she has experienced any of the following:
Ø Headaches
Ø Behavior changes
Ø Increased somnolence
Ø Decreased alertness
Ø Decreased attention span
Ø Lethargy, muscle weakness
Ø Diminished appetite
Ø Weight loss
Ø Increased fatigue
Listing activities in the previous 24 hours may disclose additional information about activity intolerance, changes in behavior, and unexplained fatigue. The nurse determines how long the client has had any of these debilitating symptoms.
PHYSICAL ASSESSMENT/CLINICAL MANIFESTATIONS Because leukemia affects all blood cells, and blood influences the health and functional capacity of all organs and systems, many areas remote from the actual site of origin of malignant cells may be affected (Chart 40-8).
The following clinical manifestations are associated with the acute leukemias (Cotran, Kumar, & Robbins, 1999). Some of these findings may also be present in the client with chronic leukemia in the blast phase.
CARDIOVASCULAR MANIFESTATIONS. Cardiovascular manifestations are usually related to anemia. The heart rate may be increased and blood pressure decreased. Murmurs (abnormal blood flow sounds through the heart) and bruits (abnormal blood flow sounds heard over arteries) may be present. Capillary filling time is increased.
RESPIRATORY MANIFESTATIONS. Respiratory manifestations are primarily associated with anemia and infectious complications. The respiratory rate increases as the degree of anemia becomes greater. If respiratory tract infections are present, the client may experience signs and symptoms of pneumonia, including cough and shortness of breath. Abnormal breath sounds are present on auscultation.
INTEGUMENTARY MANIFESTATIONS. The skin and mucous membranes may manifest abnormalities. The skin may be pale and cool to the touch as a result of accompanying anemia. Pallor is especially evident on the face, around the mouth, and in the nail beds. The conjunctiva of the eye also is pale, as are the creases on the palm of the hand (most evident when the skin over the palm of the hand is stretched). Petechiae (raised red spots) may be present on any area of skin surface, especially the lower extremities (Dietz, 1999). The petechiae may be unrelated to any obvious trauma. The nurse carefully inspects for any skin infections or traumatized areas that have failed to heal. The mouth is inspected for evidence of bleeding from the gums and any sore or lesion of the oral cavity indicating infection.
GASTROINTESTINAL MANIFESTATIONS. Gastrointestinal manifestations may be related to an increased tendency toward bleeding and to fatigue. Weight loss, nausea, and anorexia are common. The nurse examines the rectal area for fissures and tests the stool for occult blood. Many clients with leukemia have diminished bowel sounds and constipation. Enlargement of the liver and spleen and abdominal tenderness also may be present from leukemic infiltration of abdominal viscera (Chielens, 1999).
CENTRAL NERVOUS SYSTEM MANIFESTATIONS. Cranial nerve disturbances, headache, papilledema as a result of leukemic infiltration of the meninges or central nervous system (CNS), and in advanced cases, seizure activity and coma may occur. Although clients often have fever, this manifestation may be more a response to infection than to malignant changes in the CNS.
MISCELLANEOUS MANIFESTATIONS. Other manifestations include bone and joint tenderness as a result of marrow involvement and bone resorption. Leukemic cell growth or infiltration may produce enlarged lymph nodes or masses.
PSYCHOSOCIAL ASSESSMENT The client with newly diagnosed leukemia is extremely anxious, because the average layperson equates a diagnosis of any cancer with a death sentence (Dietz, 1999). Current therapies have greatly improved the prognoses of most cancers, yet the public is largely unaware of these advances. The nurse spends time with the client and family to ascertain what the diagnosis means to them and what they expect from the future. Without knowing the client’s expectations and feelings, the nurse cannot educate and provide support in an individualized manner or develop a meaningful plan of care. A diagnosis of leukemia has dramatic implications for a person’s lifestyle. Hospitalization for initial treatment often lasts several weeks and may result in boredom, loneliness, and isolation. The nurse assesses coping patterns, including activities that the client finds enjoyable and methods that help the client to relax. A plan of care to prevent diversional activity deficit is particularly beneficial. After initial therapy, the client may be able to resume work, depending on his or her occupation. However, he or she often must make adjustments to accommodate changes in functional status. Repeated hospitalizations may also be necessary.
LABORATORY ASSESSMENT The client with acute leukemia usually has decreased hemoglobin and hematocrit levels, a decreased platelet count, and an altered white blood cell (WBC) count. The WBC count may be low, normal, or elevated but usually is quite elevated; counts of 20,000 to 100,000 are common. The client with a higher WBC count on diagnosis has a poorer prognosis (Dietz, 1999). The definitive test for leukemia includes various examinations of cells obtained from bone marrow aspiration and biopsy. The bone marrow is full of leukemic blast phase cells (immature cells that are dividing). The composition of various proteins (antigens) on the surfaces of the leukemic cells helps diagnose the type of leukemia (Scheinberg, Mazslak, & Weiss, 1997). Such markers include the Til protein, the enzyme terminal deoxynucleotidyl transferase (TDT), and the common acute lymphoblastic leukemia antigen (CALLA). These markers also indicate the prognosis. Blood-clotting times and factors are usually abnormal for the client with acute leukemia. Reduced levels of fibrinogen and other coagulation factors are typical. Whole blood-clotting time (Lee-White clotting test) is increased, as is the activated partial thromboplastin time (aPTT). Chromosome analysis of the malignant bone marrow cells may identify specific marker chromosomes to assist in the diagnosis of the type of leukemia, predict the prognosis, and determine the effectiveness of therapy. An example is the Philadelphia chromosome, which is important in the diagnosis of chronic myelogenous leukemia (CML) (Chielens, 1999).
RADIOGRAPHIC ASSESSMENT Specific symptoms determine the need for specific tests. For example, in a client with dyspnea, a chest x-ray study is needed to determine whether leukemic infiltrates are present in the lung. Skeletal x-ray films may help to determine whether bone resorption (loss of bone minerals and density) is present.
Analysis
COMMON NURSING DIAGNOSES AND COLLABORATIVE PROBLEMS The following are commoursing diagnoses for adult clients with acute myelogenous leukemia (AML), the most common type of adult leukemia:
1. Risk for Infection related to decreased immune response
2. Risk for Injury related to thrombocytopenia
3. Fatigue related to decreased tissue oxygenation and increased energy demands
The primary collaborative problem is Potential for Antineoplastic Therapy Adverse Effects.
ADDITIONAL NURSING DIAGNOSES AND COLLABORATIVE PROBLEMS In addition to the commoursing diagnoses and collaborative problems, clients with AML may have one or more of the following:
• Impaired Skin Integrity related to prolonged immobility
• Impaired Oral Mucous Membrane related to effects of chemotherapy and pancytopenia
• Self-Care Deficit (Total) related to progressive debilitation and weakness
• Imbalanced Nutrition: Less Than Body Requirements related to anorexia, nausea, and vomiting
• Anxiety related to fear of death
• Powerlessness related to an inability to control disease progression
• Interrupted Family Processes related to acute, life-threatening illness of a family member
• Ineffective Role Performance related to perceived inability to fulfill parental and other family roles and prolonged hospitalization
• Deficient Diversional Activity related to prolonged hospitalization.
Planning and Implementation
RISK FOR INFECTION
PLANNING: EXPECTED OUTCOMES.
The client with leukemia is expected to:
• Remain free of cross-contamination-induced infection
• Remain free of autocontamination-induced infection
• Not experience sepsis
INTERVENTIONS. Infection is a major cause of death in the immunosuppressed client, and septicemia is a common complication (Pittinger, 1999). Infection of the client with leukemia occurs through both autocontamination (normal flora overgrows and penetrates the internal environment) and cross-contamination (microorganisms from another person or the environment are transmitted to the client). The three most common sites of infection are the skin, respiratory tract, and gastrointestinal tract. Gram-negative bacteria are most often the cause of infection, although gram-positive and fungal infections do occur. Interventions aim to interrupt or halt the process of infection and control specific infections early. Chart 40-9 emphasizes the importance of thorough assessment for the client at risk for infection.
DRUG THERAPY FOR LEUKEMIA. Drug therapy for clients with AML is divided into three distinctive phases: induction, consolidation, and maintenance.
INDUCTION THERAPY. Induction therapy is intensive and consists of combination chemotherapy initiated at the time of diagnosis. This therapy is aimed at achieving a rapid, complete remission of all manifestations of disease. Institutions and physicians differ in agents used and the treatment schedule, but a typical course of aggressive chemotherapy includes IV administration of cytosine arabinoside for 7 days with concomitant administration of daunorubicin for the first 3 days (Dietz, 1999). A major side effect of these agents is severe bone marrow suppression. As a result, the client becomes even more vulnerable to infection than before the treatment started. Prolonged hospitalizations are common while the client is immunosuppressed. Recovery of bone marrow function requires at least 2 to 3 weeks, during which time the client must be protected from life-threatening infections. Other adverse reactions include nausea, vomiting, diarrhea, alopecia (hair loss), stomatitis (mouth sores), kidney toxicity, liver toxicity, and cardiac toxicity. (See Chapter 25 for information oursing management of adverse reactions to anticancer agents.)
CONSOLIDATION THERAPY. Consolidation therapy usually consists of another course of either the same agents used for induction at a different dosage or a different combination of chemotherapeutic agents (Dietz, 1999). This treatment occurs early in remission, and its intent is to cure. At some institutions, consolidation therapy is a single course of chemotherapy; at others, it involves regularly scheduled, repeated courses of chemotherapy for 1 to 2 years.
MAINTENANCE THERAPY. Maintenance therapy may be prescribed for months to years after successful induction and consolidation therapies. It is commonly indicated for clients with acute lymphocytic leukemia (ALL). The purpose is to maintain the remission achieved through induction and consolidation. Maintenance agents are milder and are often given orally for 2 to 5 years. There are conflicting data regarding the effectiveness of maintenance therapy. Maintenance therapy is not beneficial for clients with AML (Dietz, 1999).
DRUG THERAPY FOR INFECTION. Drug therapy is the primary defense against infections that develop in clients undergoing therapy for AML. Agents used depend on the sensitivity of the specific organism causing the infection, as well as the extent of the infection, and are categorized by specificity as antibacterial, antiviral, or antifungal. Figure 40-2 outlines pharmacologic management of the febrile neutropenic client.
ANTIBIOTIC AND ANTIBACTERIAL AGENTS. Antibiotic and antibacterial agents used for prophylaxis or treatment of infection in clients with AML usually include at least one of the aminoglycoside antibiotics (amikacin, gentamicin, and tobramycin) and a systemic penicillin. Additional, powerful antibiotics used may include vancomycin and drugs from the tetracycline and third-generation cephalosporin classes.
ANTIFUNGAL AGENTS. Systemic antifungal agents, used when a fungal infection has been diagnosed or is strongly suggested, include amphotericin B, ketoconazole (Nizoral), and nystatin (Mycostatin, Nadostine, Nilstat). Ieutropenic clients, antifungal creams (e.g., miconazole nitrate) are administered intravaginally to prevent yeast infections.
ANTIVIRAL AGENTS. Antiviral agents are commonly used in clients with leukemia to prevent and treat viral infections. Acyclovir is administered either orally or parenterally before the initiation of antineoplastic agents, especially in clients who are cytomegalovirus (CMV) positive. If a viral infection is suspected or diagnosed with positive cultures, pharmacologic treatments may include ganciclovir, foscarnet, or steroids. The antivirals, although helpful in combating severe infections, are associated with a wide range of serious adverse effects, especially ototoxicity (disruption of hearing and/or balance) and nephrotoxicity (disruption of kidney function). The nurse carefully monitors the client treated with such drugs for signs of hearing impairment and renal insufficiency.
INFECTION PROTECTION. A major objective in caring for the client with leukemia is protection from infection (Chart 40-10).
Nurses and all assistive nursing personnel must use extreme care during all nursing procedures. Frequent, thorough handwashing is of the utmost importance. Anyone with an upper respiratory tract infection who must enter the client’s room must wear a mask. Nurses must also observe strict procedures when performing dressing changes or when helping a physician to insert a central venous catheter. The nurse maintains strict aseptic technique in the care of these catheters at all times. If possible, the nurse ensures that the client is in a private room to minimize cross-contamination. Because infection in the immunosuppressed person is most commonly caused by normal body microorganisms, protective (reverse) isolation has been eliminated from the Centers for Disease Control and Prevention (CDC) guidelines for infection control (see the Evidence-Based Practice for Nursing box on p. 852). However, other environmental precautions are heeded, such as allowing no standing collections of water in vases, denture cups, or humidifiers in the client’s room, because they are excellent breeding grounds for microorganisms. Some institutions prescribe a “minimal bacteria diet” during the neutropenic period. Any uncooked foods, such as raw fruits and vegetables, and pepper are eliminated from the diet because they contain large numbers of microorganisms.
Whether clients benefit from this diet is controversial. In some institutions, the immunosuppressed client is placed in a room with a high-efficiency particulate air (HEPA) filtration or laminar airflow system. These systems decrease the number of airborne pathogens. Again, whether these restrictions benefit clients is debatable.
The nurse continually assesses the client for the presence of infection. This task is difficult because manifestations of infection may not be obvious in the client with leukopenia. The development of fever and the formation of pus (both common indicators of infection) depend on the presence of leukocytes. Therefore the client with leukopenia may have a severe infection without pus and with a relatively low fever. The nurse monitors the client’s daily complete blood count (CBC) with differential white blood cell (WBC) count. The oral mucosa is inspected during every nursing shift for lesions indicating fungal or viral infection.
The nurse also auscultates the lungs every 8 hours for crackles, wheezes, or diminished breath sounds. Each time the client voids, the urine is assessed for odor and cloudiness. The client is asked about any urgency, burning, or pain present on urination. Vital signs are taken at least every 4 hours to assess for fever. A temperature elevation of even 0.5° F (or 0.5° C) above baseline is significant for a client with leukopenia and indicates infection until it has been proved otherwise. Many hospital units that specialize in the care of clients with neutropenia have specific protocols for antibiotic therapy if infection is suspected.
Usually, physicians are notified immediately, and specific specimens are obtained for culture. Blood for bacterial and fungal cultures is obtained from peripheral sites and from the central venous catheter. Urine specimens, sputum specimens, and specimens from open lesions are taken for culture, and chest x-ray films are taken. After the specimens are obtained, the client begins a regimen of IV antibiotics.
SKIN CARE. Skin care is important for preventing infection in the client with leukemia. The skin may be the only intact defense. The nurse teaches the ambulatory client thorough hygiene care and encourages daily bathing. If the client is immobile, turning is necessary every hour and skin lubricants are applied.
RESPIRATORY CARE. Respiratory care, including pulmonary hygiene, is performed every 2 to 4 hours. The nurse auscultates the lungs for crackles, wheezes, or diminished breath sounds. The client is encouraged to cough and deep breathe or to perform sustained maximal inhalations every hour while awake.
BONE MARROW TRANSPLANTATION. Once viewed as a treatment of last resort, bone marrow transplantation (BMT) is now considered a standard treatment for the client with leukemia. This treatment modality began more than 25 years ago (Johns, 1998). BMT is the treatment of choice for the client with leukemia who has a closely matched donor and who is experiencing temporary remission with induction therapy. Because of the success of BMT in the client with leukemia, this therapy is now being used for lymphoma, aplastic anemia, inborn errors of metabolism, and many solid tumors (Wolf, 1999). The bone marrow is the actual site of production of leukemic cells. Because it can be difficult to ensure that all leukemic cells have been eradicated during induction therapy, the goal is for extremely high doses of chemotherapy to destroy all of the affected marrow. The new, healthy marrow then begins the process of hematopoiesis, which results iormal, properly functioning cells and, it is hoped, a permanent cure. For many malignant disorders, the dose-limiting toxicity of treatments is bone marrow suppression.
The aim of bone marrow or stem cell transplantation is to rid the client of all leukemic or other malignant cells through high doses of chemotherapy, often in conjunction with whole-body irradiation. These treatments are lethal to the bone marrow, and without replacement of bone marrow function through transplantation of progenitor cells of the hematopoietic system, the client would die of infection or hemorrhage. Advances in the field of transplantation have been remarkable. Even as recently as the late 1980s, the client undergoing transplantation would have been seen only in major medical centers. Today, transplant units are becoming commonplace, even in community hospital settings. With long-term survival after transplantation increasing, nurses can expect to be caring for these people, if not during the actual transplantation or recovery period, then during the post-transplantation period, in a variety of health care settings.
SOURCES OF STEM CELLS. BMT originated with the use of allogeneic bone marrow transplantation (transplantation of identical bone marrow from a sibling) and has advanced to the use of human leukocyte antigen (HLA)-matched stem cells from the umbilical cords of unrelated donors (Wolf, 1999). Transplants can be classified based on the source of stem cells. In autologous transplants, the clients receive their own stem cells, which were collected before therapy. Syngeneic transplants are rare and involve the client’s own identical twin as the donor of stem cells. In allogeneic transplants, a closely HLA-matched sibling or an unrelated donor provides the stem cells. Stem cells for transplantation may be obtained by one of the following methods: bone marrow harvest, peripheral stem cell pheresis, or umbilical cord blood stem cell banking. Table 40-5 provides an overview of the types of transplants. Transplantation procedures have five phases: stem cell procurement, conditioning regimen, transplantation, engraftment, and post-transplantation recovery.
OBTAINING STEM CELLS. Stem cells for transplantation are obtained either by harvest of bone marrow, by pheresis for peripheral blood stem cells, or by collection of umbilical cord stem cells. Bone marrow is harvested either from the client directly (autologous marrow) or from an HLA-matched person (allogeneic marrow).
For allogeneic marrow, a suitable donor is selected after family members are tested for HLA type. Preferred transplantations are those between HLA-identical siblings, but transplantation can also be successful between those with closely matched HLA types. The chance of matching with any given sibling is 25%. Several donor registries have been formed that keep records of people willing to donate marrow to provide marrow for clients who do not have a family member HLA match. The chance of matching with an unrelated donor is one in 5000 (Alcoser & Burchett, 1999).
After a suitable donor is identified by tissue typing, the donor is taken to the operating room, where sufficient marrow for transplant is harvested through multiple aspirations aspirated; this amount is approximately 5% to 10% of the donor’s marrow supply and will be replenished in a few weeks (Poliquin, 1997).
The marrow is then filtered and may be further processed to purge the autologous marrow of any residual cancer cells or to deplete the allogeneic marrow of T-cells, which may later cause graft-versus-host disease (GVHD) (see p. 855). Allogeneic marrow is transfused into the recipient immediately; autologous marrow is frozen for later use. The nurse monitors the donor for signs and symptoms of fluid loss, assesses for complications of anesthesia, and manages postoperative pain. During surgery, donors may lose a significant amount of fluid in addition to the volume of marrow donated. Donors are often hydrated with saline infusions before and immediately after surgery. Occasionally the donor may require an infusion of autologous salvaged red blood cells (RBCs) (Poliquin, 1997). The nurse assesses the harvest sites to ensure that the dressings are dry and intact and that the donor is not bleeding excessively. Marrow donation is usually a same-day surgical procedure. At home the donors are taught to inspect the harvest sites for bleeding and to take analgesics for pain. Pain is often experienced at the harvest sites (hip) and is usually managed effectively with oral non-aspirin-containing analgesics. Individual differences do occur, however. Some donors refuse pain medication, but others require opioid analgesics.
There are three phases to obtaining peripheral blood stem cells (PBSCs): mobilization, collection, and reinfusion. During the mobilization phase, chemotherapy or hematopoietic growth factors are administered to the client (Wagner & Quinones, 1998). These agents cause stem cells to circulate in the peripheral blood and the number of WBCs to increase. The stem cells are then collected by pheresis (withdrawing whole blood, filtering out the cells, and returning the plasma to the client). One to five pheresis procedures, each lasting 2 to 4 hours, are usually required to obtain enough stem cells for PBSC transplantation.
The stem cells are then frozen and stored for reinfusion after the conditioning regimen (Wolf, 1999). The nurse must monitor the client closely during pheresis. Common complications include catheter clotting, which may delay pheresis, and hypocalcemia caused by anticoagulants (Poliquin, 1997). The client with hypocalcemia may experience chills, paresthesia, abdominal or muscle cramping, or chest pain, and the nurse may need to administer oral calcium supplements to manage these symptoms.
The nurse must also monitor vital signs frequently. The client may experience hypotension as a result of fluid volume changes during the procedure. Stem cells may also be obtained from umbilical cords. The first cord blood transplant was done in France in 1988 (Wolf, 1999). Umbilical stem cells are obtained via a simple phlebotomy procedure. After birth, before the placenta detaches, a syringe is used to withdraw 40 to 150 mL of blood from the umbilical vein. The syringes are placed in a kit, which is returned to the Cord Blood Registry for processing and storage (Wolf, 1999). The stem cells may be used later for an unrelated recipient or stored in case the infant develops a serious illness later in life and needs them. The cost of banking and processing umbilical cord stem cells is approximately $1500, with an additional charge of $100 per year for storage. Umbilical stem cells can last for years when stored properly in liquid nitrogen. The oldest viable sample is nearly 20 years old (Wolf, 1999).
CONDITIONING REGIMEN. Figure 40-3 outlines the timing and steps typically involved in BMT. The day the client receives the bone marrow is considered day T-0.
Pretransplantation conditioning days are counted in reverse chronologic order from T-0, just like a rocket countdown. Post-transplantation days are counted in chronologic order from the day of transplantation. The client must first undergo a conditioning regimen, which varies with the diagnosis and type of transplant to be received. The conditioning regimen serves two purposes: (1) to obliterate, or “wipe out,” the client’s own bone marrow, thus preparing the client for optimal graft take, and (2) to give higher thaormal doses of chemotherapy and/or radiotherapy to obliterate, or wipe out, a malignancy, such as breast cancer. Usually a period of 5 to 10 days is required. The conditioning regimen always includes intensive chemotherapy and sometimes includes radiotherapy, usually total-body irradiation (TBI). Each conditioning regimen is individually tailored, with the client’s specific disease, overall health, and previous treatment taken into account (Poliquin, 1997). A typical conditioning regimen for an adult client receiving an allogenic BMT for treatment of acute myelogenous leukemia (AML) is as follows:
Days T-7 through T-5: High-dose chemotherapy to obliterate the client’s own bone marrow cells and to eradicate any remaining leukemic cells. Specific agents include busulfan, carmustine, cyclophosphamide, cytosine arabinoside, etoposide, and melphalan. The dosages are many times higher than those used for normal chemotherapy.
Days T-4 through T-2: Delivery of fractionated TBI (smaller doses of radiation given over a period of time instead of one larger dose). The typical radiation dose for TBI is 1200 rad. The client usually receives no cellkilling treatment on day T-l. During conditioning, bone marrow and normal tissues begin to respond immediately to the chemotherapy and radiotherapy. The client experiences all of the expected side effects associated with both therapies. Because the chemotherapy is administered in such high doses, these side effects are much more intense than those seen with either standard chemotherapy or radiation. These side effects include severe nausea and vomiting, mucositis, capillary leak syndrome, diarrhea, and bone marrow suppression (Poliquin, 1997). Late effects from the conditioning regimen are also common, occurring as late as 3 to 10 years after transplantation, and include veno-occlusive disease (VOD), skin toxicities, cataracts, fibrotic pulmonary disease, secondary malignancies, cardiomyopathy, endocrine complications, and neurologic complications (Poliquin, 1997).
TRANSPLANTATION. Day T-0, the day of transplantation, is separated from the chemotherapy conditioning by at least 2 days to ensure that the chemotherapeutic agent has cleared and will not exert any cytotoxic effects on the transplanted stem cells. The client should have few, if any, circulating white blood cells (WBCs) at this point, indicating successful conditioning. The transplantation itself is very simple. Frozen marrow, PBSCs, or umbilical cord blood cells are thawed in a temperature- controlled warm water bath (D’Andrea et al., 1997). The bone marrow is administered through the client’s central catheter like an ordinary blood transfusion, but not using blood administration tubing. Usually the marrow is infused over a 30-minute period, although it may also be administered by IV push directly into the central catheter with syringes. Side effects of all types of stem cell transfusions are similar. The client may experience fever and hypertension as a result of a reaction to the preservative used for storage of stem cells (D’Andrea et al., 1997). To prevent these reactions, the nurse administers acetaminophen (Tylenol), hydrocortisone, and diphenhydramine (Benadryl) before the transfusion (Johns, 1998). Antihypertensives or diuretics may also be required to treat fluid volume changes. The client may experience red urine secondary to hemolysis of erythrocytes in the infused product.
ENGRAFTMENT. The transfused PBSCs and marrow cells circulate only briefly in the peripheral blood. Most of the cells, especially the stems cells, find their way to the marrowforming sites of the recipient’s bones and establish residency there. The mechanism by which the donated marrow cells “home in” on the appropriate sites is not yet understood. Engraftment, successful “take” of the transplanted cells in the recipient’s bone marrow, is key to the whole transplantation process. For the donated marrow or stem cells to “rescue” the client after large doses of chemotherapy and/or radiotherapy wipe out his or her own bone marrow, the transfused stem cells must survive and grow in the clients’ bone marrow sites. The engraftment process takes 8 to 12 days for peripheral blood stem cells and 12 to 28 days for bone marrow stem cells (Poliquin, 1997). To facilitate engraftment, hematopoietic growth factors, such as granulocyte colony-stimulating factor or granulocyte-macrophage colonystimulating factor, may be administered (Alcoser & Burchett, 1999). When engraftment is successful, the client’s WBC, erythrocyte, and platelet counts begin to rise.
PREVENTION OF COMPLICATIONS. The post-transplantation period is difficult. Because the client remains without any natural immunity until the transfused stem cells begin to proliferate and engraftment occurs, infection and severe thrombocytopenia are major problems. The nursing care requirements for this client are virtually identical to those for the client undergoing aggressive induction therapy for AML. Helping the client to maintain hope through this long recovery period is difficult (Campbell, 1999). Complications are often severe and life threatening.
The nurse should try to encourage the client to maintain a positive attitude and be involved in his or her own recovery. In addition to the problems related to the period of pancytopenia (too few circulating blood cells), other immediate hazards associated with BMT include failure to engraft, development of GVHD, and VOD.
Failure to Engraft. Sometimes the donated marrow or stem cells fail to engraft. This possibility is discussed in advance with the client and the donor. Failure to engraft occurs more often among allogeneic stem cell recipients than among autologous stem cell recipients. The causes may be related to insufficient numbers of cells transplanted, attack or rejection of donor cells by the remaining immunologically competent recipient cells, infection of transplanted cells, and unknown biologic factors. If the transplanted stem cells fail to engraft, the client will die unless another transplantation is successful.
Graft-Versus-Host Disease. Graft-versus-host disease (GVHD) is an immunologic event that occurs in allogeneic transplants. The immunocompetent cells of the donated marrow recognize the client’s (recipient) cells, tissues, and organs as foreign and mount an immune offense against them. The graft is actually trying to attack the host (Alcoser & Burchett, 1999). Although all host tissues can be attacked and harmed, the tissues most commonly damaged are the skin, gastrointestinal tract, and liver. Approximately 25% to 50% of all allogeneic BMT recipients experience some degree of GVHD, and more than 15% of the clients who experience GVHD die of its complications (Johns, 1998). The presence of GVHD indicates that the transplanted cells are competent and have successfully engrafted. Management of GVHD is achieved by limiting the activation of donor T-lymphocytes through the administration of immunosuppressive agents such as cyclosporine, methotrexate, corticosteroids, and antithymocyte globulin (Alcoser & Burchett, 1999). Care is taken to avoid suppressing the new immune system to the extent that either the client becomes more susceptible to infection or the transplanted cells stop engrafting.
Veno-occlusive Disease. Veno-occlusive disease (VOD) involves occlusion of the hepatic blood vessels by clotting and inflammation (phlebitis). This condition occurs in up to 20% of clients who receive either an autologous or an allogeneic transplant, and symptoms usually occur within the first 30 days after transplantation (Johns, 1998). Clients who have received high doses of chemotherapy, especially alkylating agents, are at risk for life-threatening hepatic complications. Clinical signs include jaundice, pain in the right upper quadrant, ascites, weight gain, and liver enlargement. Because there is no known way of opening the hepatic vessels, treatment is supportive. Early detection enhances the chances of survival. Fluid management is also crucial. The nurse assesses the client daily for weight gain, fluid accumulation, increases in abdominal girth, and hepatomegaly.
RISK FOR INJURY
Because normal bone marrow production is severely limited with acute myelogenic leukemia (AML), the number of circulating platelets is severely diminished, causing thrombocytopenia. This condition puts the client with AML at a greatly increased risk for excessive bleeding in response to minimal trauma. Thrombocytopenia can also be induced by induction therapy for AML or high-dose chemotherapy for transplantation (Rust, Wood, & Battiato, 1999).
PLANNING: EXPECTED OUTCOMES. The client with leukemia is expected to remain free from bleeding. INTERVENTIONS. As a result of chemotherapy-induced pancytopenia, the client’s platelet count is decreased. During the period of greatest bone marrow suppression (the nadir), the platelet count may be extremely low (<10,000/mm3). The client is at great risk for bleeding once the platelet count falls below 50,000/mm3, and spontaneous bleeding often occurs when the platelet count is lower than 20,000 (Harrahill & DeLoughery, 1998).
BLEEDING PRECAUTIONS. The nurse’s major objectives are to protect the client from situations that could lead to bleeding and to closely monitor any bleeding that does occur. The nurse assesses the client frequently for evidence of bleeding: oozing, confluent ecchymoses, petechiae, or purpura. All stools, urine, nasogastric drainage, and vomitus are examined visually for blood and tested for occult blood. The nurse measures any blood loss as accurately as possible and measures the client’s abdominal girth daily. Increases in abdominal girth can indicate internal hemorrhage. Bleeding precautions are instituted (Chart 40-11).
The nurse also monitors laboratory values daily. Complete blood count (CBC) results are reviewed daily to determine the risk for bleeding, as well as actual blood loss. The client with a platelet count below 20,000/mm3 may need a platelet transfusion. An alternative treatment is the administration of oprelvekin (Neumega), a platelet (thrombopoietic) growth factor. The recommended dose is 50 xg/kg/day subcutaneously starting 6 to 12 hours after the completion of chemotherapy (Rust, Wood, & Battiato, 1999). For the client with severe blood loss, packed RBCs may be ordered.
FATIGUE
Because normal bone marrow production is severely limited in leukemia, the number of circulating erythrocytes is severely diminished, creating a condition of anemia, leading in turn to fatigue. Because leukemic cells tend to have higher rates of metabolism and greater utilization of oxygen, the anemic client with leukemia is at risk for severe fatigue. Anemia also occurs secondary to chemotherapy treatment (Richardson, Ream, & Wilson-Barnett, 1998).
PLANNING: EXPECTED OUTCOMES.
The client with leukemia is expected to:
• Experience no increase in fatigue
• Recognize symptoms of fatigue and alter activity before fatigue becomes excessive
INTERVENTIONS
ENERGY MANAGEMENT. Energy management aims at decreasing the effects of anemia and conserving energy expenditure (see Chart 40-10).
DIET THERAPY. Diet therapy is indirectly related to fatigue and subsequent activity intolerance. The client must ingest enough calories to meet at least basal energy requirements, but increasing dietary intake can be difficult when the client is extremely fatigued. The nurse thus provides small, frequent meals high in protein and carbohydrates. Food items that are liquid or easy to chew also require less effort to eat.
BLOOD REPLACEMENT THERAPY. Blood transfusions are sometimes indicated for the client with fatigue. Transfusions increase the blood’s oxygen-carrying capacity and replace missing red blood cells (RBCs) and some coagulation factors (see Table 40-2). For the client with leukemia who is experiencing fatigue related to anemia, packed RBCs are usually the blood component of choice. (See Transfusion Therapy, p. 862, for a discussion of nursing care during transfusions.)
DRUG THERAPY. Clients may receive subcutaneous injections of epoetin alfa (Epogen or Procrit) 50 to 100 units/kg three times per week (Cella & Bron, 1999). This growth factor is naturally secreted by the kidney and boosts the production of RBCs. Epoetin alfa has previously been used in anemia associated with chronic renal failure and in clients with human immunodeficiency virus (HIV) who are receiving zidovudine and is now approved for use in anemia associated with chemotherapy. The nurse administers injections three times a week and assesses for side effects such as hypertension, headaches, fever, myalgia (muscle aches), and rashes.
CONSERVATION OF ENERGY. The nurse examines the hospitalized client’s schedule of prescribed and routine activities. Those activities that do not have a direct positive effect on the client’s condition are assessed in terms of their usefulness. If the actual or potential benefit of an activity is less than its actual or potential worsening of fatigue, the nurse consults with other members of the health care team about eliminating or postponing it. Candidates for cancellation or postponement include physical therapy and certain invasive diagnostic tests not required for assessment or treatment of current problems.
Community-Based Care The client with leukemia is discharged after induction chemotherapy and recovery of blood cell-producing function. Follow-up care is provided on an outpatient basis. Although the majority of transplant centers discharge clients following engraftment, some centers administer high-dose chemotherapy and stem cell infusion on an outpatient basis. This plan involves daily clinic visits and frequent follow-up by nurses in the home care setting (D’Andrea et al., 1997).
HOME CARE MANAGEMENT
Planning for home care for the client with leukemia begins as soon as a client achieves remission. He or she will need assistance at home until the condition improves. The nurse assesses the available support mechanisms. Many clients require the services of a visiting nurse to assist with dressing changes for central venous catheters, to assist with hyperalimentation infusions, to transfuse platelets, and to answer questions. Occasionally they may also require home transfusion therapy for one or more blood components (Bean, 1998). The home care team is critical for the client receiving stem cell transplantation in the home setting. Potential candidates are evaluated in advance. Criteria include a knowledgeable caregiver, a clean home environment, close proximity to the hospital, telephone access, and emotional stability on the part of the client and caregiver (Herrmann et al., 1998). In one sample program, clients receive their daily dose of chemotherapy in the outpatient clinic in the morning and then receive a home visit in the evening. Home care nurses administer chemotherapy and monitor the client for complications. Nurses visit the client once or twice a day and spend between 4 and 8.5 hours per day in the home (D’Andrea et al., 1997). The client receives the stem cell transplant infusion in the outpatient clinic. Nursing care is similar to that provided in the hospital. If serious complications such as sepsis or veno-occlusive disease occur, the client is admitted to the inpatient facility
HEALTH TEACHING
The client and the family need to be educated about the importance of continuing therapy and appropriate medical follow-up, despite the unpleasant side effects of therapy. Many clients go home with a central venous catheter in place and require instructions about its care and maintenance (Bean, 1998). Chart 40-12 lists general guidelines for central venous catheter care at home.
These guidelines may be altered depending on the home setting, assistance available, and agency policy. Protecting the client from infection after discharge from the hospital is just as important as it was during hospitalization. The nurse urges the client to use proper hygiene and to avoid crowds or others with infections. Neither the client nor any household member should receive live virus immunization (poliomyelitis, measles, or rubella) for 2 years after transplantation (Alcoser & Burchett, 1999). The client should continue mouth care regimens at home. The nurse emphasizes that the client should immediately notify the physician if he or she experiences fever or any other sign of infection.
Chart 40-13 lists guidelines for clients for the prevention of infection.
Because platelet recovery is usually slower than recovery of white blood cells (WBCs), many clients return home still at risk for bleeding. Thrombocytopenia may be present for 6 months following transplantation (Hurley, 1997). The nurse reinforces the safety and bleeding precautions initiated in the hospital, emphasizing that the client must follow these precautions until the platelet count is above 50,000. The client and family are instructed to assess for petechiae, avoid trauma and sharp objects, apply pressure to wounds for 10 minutes, and report any unusual symptoms, including blood in the stool or urine, or headache that does not respond to acetaminophen. Chart 40-14 lists guidelines for clients at risk for bleeding.
PSYCHOSOCIAL PREPARATION The nurse’s responsibility in psychosocial preparation of the client before discharge is very important. A diagnosis of leukemia threatens self-esteem and the family role. The client is confronted with the reality of death, and treatment causes major adjustments in self-image. The client and family also experience changes in the client’s body image, level of independence, and lifestyle. Some feel threatened by their environment, seeing everything as potentially infectious. Clients who are cared for in protective isolation may experience loneliness and loss of contact with the outside world (Campbell, 1999). The nurse helps the client and family redefine priorities, understand the illness and its treatment, and find hope. The nurse makes referrals to support groups sponsored by organizations such as the American Cancer Society (“I Can Cope” and “Make Today Count”), which can be enormously beneficial to both the client and the family.
HEALTH CARE RESOURCES The client with limited social support may need assistance at home until strength and energy return. A home care aide may suffice for some clients, whereas for others a visiting nurse may be needed to reinforce teaching. The client may also need equipment to facilitate activities of daily living (ADLs) and ambulation. Financial resources are assessed. Treatment of cancer is expensive, and the nurse works closely with the local social services department to ensure that insurance is adequate. If the client is uninsured, other sources, such as drug company-sponsored compassionate aid programs, are ex plored. The Leukemia Society of America offers limited financial assistance for clients with leukemia, sponsors support groups, and provides publications for clients and health care providers. Prolonged outpatient contact and follow-up will be necessary, and clients will need transportation to the outpatient facility. Many local divisions of the American Cancer Society offer free transportation to clients with cancer, including leukemia.
Evaluation: Outcomes
The nurse evaluates the care of the client with leukemia on the basis of the identified nursing diagnoses and collaborative problems. The expected outcomes include that the client will:
• Remain free of cross-contamination-induced infection
• Remain free of autocontamination-induced infection
• Not experience sepsis
• Remain free of episodes of bleeding
• Balance activity and rest
• Use energy conservation techniques
• Adapt lifestyle to energy level
Malignant lymphoma
Malignant lymphomas occur as a result of abnormal overgrowth of one type of leukocyte (lymphocytes); they differbone marrow, and they fall into two major categories among adults: Hodgkin’s lymphoma and non-Hodgkin’s lymphoma.
Hodgkin’s Lymphoma i OVERVIEW
Hodgkin’s lymphoma is a cancer that can affect any age-group, although incidence peaks first in people in their mid-to-late 20s and then in people older than 50 years of age (Callaghan, 1998). Men and women are affected equally in the first group, but the disease is more prevalent in men in the older group. Factors implicated as possible causes of Hodgkin’s lymphoma include viral infections and previous exposure to alkylating chemical agents. This cancer usually originates in a single lymph node or a single chain of nodes. The lymphoid tissues within the node undergo malignant transformation, usually initiating some inflammatory processes. These nodes contain a specific transformed cell type, the Reed-Sternberg cell, a marker for Hodgkin’s lymphoma. The disease first metastasizes (spreads) to other nearby lymphoid structures and eventually invades nonlymphoid tissues. »
COLLABORATIVE MANAGEMENT
Assessment Assessment most often reveals a greatly enlarged but painless lymph node or nodes, usually the earliest manifestation of Hodgkin’s lymphoma. The client also often experiences fever, malaise, and night sweats (Table 40-6). More specific clinical manifestations depend on the site (or sites) of malignancy and the extent of disease. Diagnosis and grade are established when biopsy of a node or mass reveals Reed-Sternberg cells (Callaghan, 1998). The client then undergoes extensive staging procedures to determine the exact extent of disease. Staging must be detailed and accurate because the treatment regimen is determined by the extent of disease (DeVita, Mauch, & Harris, 1997). Staging procedures for Hodgkin’s lymphoma include biopsies of distant lymph nodes, computed tomography (CT) of the thorax and abdomen, staging laparotomy, a complete blood count (CBC), liver function studies, and bilateral bone marrow biopsies.
Interventions Such great progress has been made in treatment regimens that Hodgkin’s lymphoma is now one of the most curable types of cancer (Callaghan, 1998). Generally, for stage I and stage II disease without mediastinal node involvement, the treatment of choice is extensive external radiation of involved lymph node regions. With more extensive disease, radiation coupled with an aggressive multiagent chemotherapy regimen is most effective in achieving a cure (DeVita, Mauch, & Harris, 1997).
Specific nursing management of the client undergoing treatment for Hodgkin’s lymphoma focuses on the side effects of therapy, especially the following:
Ø Drug-induced pancytopenia, which results in increased risk for infection, bleeding, and anemia
Ø Severe nausea and vomiting
Ø Skin irritation and breakdown at the site of radiation from the leukemias in the degree of maturation of the affected cells and the location of cell production.
Ø Impaired hepatic function either by metastasis to the liver or by multiagent chemotherapy
Ø Permanent sterility for male clients receiving radiation to the abdominopelvic region in the pattern of an inverted Y in combination with specific chemotherapeutic agents (the client should be informed of this side effect and given the option to store sperm in a sperm bank before treatment)
Ø Secondary malignancies for clients receiving radiation alone or chemotherapy (Long-term follow-up should include screening for recurrence, as well as the possible development of a secondary cancer.)
Non-Hodgkin’s Lymphoma
OVERVIEW Non-Hodgkin’s lymphoma is the classification for all cancers originating from lymphoid tissues that are not diagnosed as Hodgkin’s lymphoma. There are more than 12 subtypes of non-Hodgkin’s lymphoma, including low-grade, intermediate, and high-grade lymphomas.
The low-grade lymphomas usually arise from B-cell lymphocytes and progress slowly. Although clients with lowgrade lymphomas have longer survival rates, the diseases are less responsive to treatment and, consequently, cures are rare (Bilodeau & Fessele, 1998).
At the other end of the spectrum are the high-grade lymphomas, which are aggressive tumors of usually mixed cellularity with rapid doubling times. High-grade lymphomas are more responsive to chemotherapy, and the chances for a longterm cure are greater.
Non-Hodgkin’s lymphoma is ranked as the sixth most common cause of cancer-related death in the United States. The disease is more prevalent in men, Caucasians, and individuals older than 50 years of age. The long-term prognosis is better for women and clients younger than 65 years of age (Bilodeau & Fessele, 1998). Most non-Hodgkin’s lymphomas arise from lymph nodes, but they can originate in virtually any tissue or organ. A low-grade lymphoma also can convert to a highergrade lymphoma. Definitive causes are unknown, but viral infection, exposure to ionizing radiation, autoimmune disorders, and exposure to toxic chemicals have all been implicated.
COLLABORATIVE MANAGEMENT
Because lymphomas may arise from lymphoid cells in any tissue and because the malignancy can spread to any organ, assessment reveals no specific clinical manifestations other than lymphadenopathy common to all types of lymphoma. Diagnosis is made from the histologic features apparent on biopsy of any suspicious node or mass. Classification of the specific lymphoma subtype is based on a complex grading of surface markers, cytogenetic features, cell size, and expression of viral antigens (Bilodeau & Fessele, 1998). Staging is similar to that for Hodgkin’s lymphoma (see Table 40-6). Treatment consists of radiation therapy and multiagent chemotherapy. Nursing care needs are similar to those for clients with Hodgkin’s lymphoma, with additional organspecific problems taken into account if the disease is widely disseminated.
COAGULATION DISORDERS
Coagulation disorders are synonymous with bleeding disorders and are characterized by abnormal or increased bleeding resulting from defects in one or more components regulating hemostasis. Bleeding disorders may be spontaneous or traumatic, localized or generalized, lifelong or acquired. They can originate from a defect in the hemostatic processes at the vascular, platelet, or clotting factor level. Figure 40-4 outlines blood-clotting cascades and sites where specific defects and drugs disrupt the hemostatic processes.
PLATELET DISORDERS Platelets play a vital role in hemostasis. For both the intrinsic and the extrinsic pathways, blood clotting starts with platelet adhesion and the formation of a platelet plug. Any condition that either reduces the number of platelets or interferes with their ability to adhere (to one another, blood vessel walls, collagen, or fibrin threads) can be manifested as increased bleeding. Platelet disorders can be inherited, acquired, or temporarily induced by the ingestion of substances that limit platelet production or inhibit aggregation. A drop in the number of platelets below the level needed for normal coagulation is called thrombocytopenia. Thrombocytopenia may occur as a result of other conditions or treatments that suppress general bone marrow activity. It also can occur through processes that specifically limit platelet formation or increase the rate of platelet destruction. The two thrombocytopenic conditions affecting adults are autoimmune thrombocytopenic purpura and thrombotic thrombocytopenic purpura.
Autoimmune Thrombocytopenic Purpura
OVERVIEW Before the underlying cause of autoimmune thrombocytopenic purpura was identified, this condition was known as idiopathic thrombocytopenic purpura (ITP). Although the cause is now thought to be an autoimmune reaction, the condition is still commonly known as ITP. The total number of circulating platelets is greatly reduced in ITP, even though platelet production in the bone marrow is normal. Clients with idiopathic thrombocytopenic purpura make an antibody directed against the surface of their own platelets (an antiplatelet antibody). This antibody coats the surface of the platelets, making them more susceptible to attraction and destruction by phagocytic leukocytes, especially macrophages. Because the spleen contains a large concentration of macrophages and because the blood vessels of the spleen are long and twisted, antibody-coated platelets are destroyed primarily in the spleen. When the rate of platelet destruction exceeds that of production, the number of circulating platelets decreases and blood clotting slows. Although the cause of this disorder appears to be autoimmune, the exact mechanism initiating the production of autoantibodies is unknown. ITP is most common among women between the ages of 20 and 40 and among people with a preexisting autoimmune condition, such as systemic lupus erythematosus (Cotran, Kumar, & Robbins, 1999).
COLLABORATIVE MANAGEMENT
Assessment Clinical manifestations associated with ITP are generally limited to the skin and mucous membranes: large ecchymoses (bruises) on the arms, legs, upper chest, and neck or a petechial rash. Mucosal bleeding occurs easily. If the client has experienced significant blood loss, signs of anemia may also be present. A rare complication is an intracranial bleeding-induced stroke. The nurse assesses for neurologic function and mental status. Family members or significant others are asked if the client’s behavior and responses to the mental status examination are typical or represent a change from usual reactions. Idiopathic thrombocytopenic purpura is diagnosed by a decreased platelet count and large numbers of megakaryocytes in the bone marrow. Antiplatelet antibodies may be present in detectable levels in peripheral blood. If the client experiences any episodes of bleeding, hematocrit and hemoglobin levels also are low.
Interventions
NONSURGICAL MANAGEMENT. As a result of the decreased platelet count, the client is at great risk for bleeding. Interventions include therapy for the underlying condition, as well as protection from trauma-induced bleeding episodes.
DRUG THERAPY. Agents used to control ITP include drugs that suppress immune function to some degree. The premise for the use of agents such as corticosteroids and azathioprine (Imuran) is to inhibit immune system synthesis of antiplatelet autoantibodies. More aggressive therapy can include low doses of chemotherapeutic agents, such as the antimitotic agents and cyclophosphamide.
BLOOD REPLACEMENT THERAPY. For the client with a platelet count of less than 20,000/mm3 who is experiencing an acute life-threatening bleeding episode, a platelet transfusion may be required. Platelet transfusions are not performed routinely, because the donated platelets are just as rapidly destroyed by the spleen as the client’s own platelets (see later discussion under Platelet Transfusions, p. 865).
MAINTAINING A SAFE ENVIRONMENT. The nurse’s major objectives are to protect the client from situations that can lead to bleeding and to closely monitor the amount of bleeding that is occurring. (For nursing care actions, see Risk for Injury [Leukemia], p. 856.)
SURGICAL MANAGEMENT. For the client who does not respond to drug therapy, splenectomy may be the treatment of choice. Because the leukocytes in the spleen perform many different immunodefensive functions, the client who has undergone a splenectomy is at increased risk for infection.
Thrombotic Thrombocytopenic Purpura
OVERVIEW Thrombotic thrombocytopenic purpura (TTP) is a rare disorder in which platelets clump together inappropriately in the microcirculation and insufficient platelets remain in the systemic circulation. The client experiences inappropriate clotting, yet the blood fails to clot properly when trauma occurs. The underlying cause of TTP appears to be an autoimmune reaction in blood vessel cells (endothelial cells) that makes platelets clump together in very small blood vessels. As a result, tissues become ischemic. Common manifestations include renal failure, myocardial infarction, and stroke. If left untreated, this condition is fatal within 3 months in 90% of clients (McBrien, 1997).
COLLABORATIVE MANAGEMENT Treatment for the client with TTP focuses on inhibiting the inappropriate platelet aggregation and disrupting the underlying autoimmune process. Primary treatment consists of plasma pheresis with the infusion of fresh frozen plasma. This treatment provides the necessary platelet aggregate inhibitors (McBrien, 1997). Drugs that inhibit platelet clumping, such as aspirin, alprostadil (Prostin), and plicamycin, also may be helpful. Immunosuppressive therapy reduces the intensity of this disorder.
CLOTTING FACTOR DISORDERS
Coagulation or bleeding disorders can result from a clotting factor defect, including the inability to produce a specific clotting factor, production of insufficient quantities, or a less active form of clotting factor. Most clotting factor disorders are congenitally transmitted gene abnormalities of one clotting factor. The few acquired clotting factor disorders are related to an inability to synthesize many clotting factors at the same time as a result of liver damage or an insufficiency of clotting cofactors and precursor products. Common congenital disorders that result in defects at the clotting factor level include hemophilias A and B and von Willebrand’s disease. Disseminated intravascular coagulation (DIC) may be considered an acquired clotting disorder but is more closely associated with septic shock.
Hemophilia
OVERVIEW Hemophilia comprises two hereditary bleeding disorders resulting from deficiencies of specific clotting factors. Hemophilia A (classic hemophilia) results from a deficiency of factor VIII and accounts for 80% of cases of hemophilia. Hemophilia B (Christmas disease) is a deficiency of factor IX and accounts for 20% of cases. The incidence of both is
COLLABORATIVE MANAGEMENT
Assessment
Assessment of the client with hemophilia reveals the following:
• Excessive hemorrhage from minor cuts or abrasions caused by abnormal platelet function
• Joint and muscle hemorrhages that lead to disabling long-term sequelae
• A tendency to bruise easily
• Prolonged and potentially fatal postoperative hemorrhage
The laboratory test results for a client with hemophilia demonstrate a prolonged partial thromboplastin time (PTT), a normal bleeding time, and a normal prothrombin time (PT) (Cotran, Kumar, & Robbins, 1999). The most common health problem associated with hemophilia is degenerating joint function resulting from chronic bleeding into the joints, especially at the hip and knee.
• Interventions The bleeding problems of hemophilia A can be well managed by either regularly scheduled IV administration of factor VIII cryoprecipitate or intermittent administration as needed, depending on the individual’s activity level and injury probability (see Cryoprecipitate, p. 865). However, the cost of cryoprecipitate is prohibitive for many people with hemophilia. In addition, because the precipitated clotting factors are derived from pooled human serum, a risk of viral contamination remains, even with the
use of heat-inactivated serum (Ligda, 1998). Major complications of hemophilia therapy during the 1980s were infection with hepatitis B virus, cytomegalovirus, and human immunodeficiency virus (HIV). Although heat-inactivated serum and the elimination of HIV-positive donors have reduced these risks, they have not yet been eliminated.
TRANSFUSION THERAPY
Any blood component may be removed from a donor and transfused to benefit a recipient. Components may be transfused individually or collectively, with varying degrees of benefit to the recipient.
PRETRANSFUSION RESPONSIBILITIES Nursing actions during transfusions aim largely at prevention or early recognition of adverse transfusion reactions. Preparation of the client for transfusion therapy is imperative, and in stitutional blood product administration procedures should be carefully followed. Before administering any blood product, the nurse reviews the agency’s policies and procedures. Chart 40-15 presents best practices for transfusion therapy.
Legally, a physician’s order is needed to administer blood or its components. The order specifies the type of component to be delivered, the volume to be transfused, and any special conditions the physician judges to be important. The nurse verifies the order for accuracy and completeness. The nurse also evaluates the need for transfusion, considering both the client’s clinical condition and the laboratory values. In many hospitals a separate consent form must be obtained for the administration of blood products before a transfusion is performed.
A blood specimen is obtained for crossmatching (testing of the donor’s blood and the recipient’s blood for compatibility). The procedure and responsibility for obtaining this specimen are specified by hospital policy. The laboratory requires at least 45 minutes to complete the crossmatch testing. In most hospitals a new crossmatching specimen is required at least every 48 hours (Dreger & Tremback, 1998).
Because of the viscosity of blood components, a 19-gauge needle or larger is used, whenever possible, for venous access. Both Y-tubing and straight tubing sets are available for blood component administration. A blood filter (approximately 170 xm) to remove aggregates from the stored blood products is included with component administration equipment and must be used to transfuse all blood products. In massive transfusion, a microaggregate filter (20 to 40 jam) may be used.
Normal saline is the solution of choice for administration. Ringer’s lactate and dextrose in water are contraindicated for administration with blood or blood products because they cause clotting or hemolysis of blood cells.
Medications are never added to blood products.
Before the transfusion is initiated, it is essential to determine that the blood component delivered is correct. Two registered nurses simultaneously check the physician’s order, the client’s identity, and whether the hospital identification band name and number are identical to those on the blood component tag. The blood bag label, the attached tag, and the requisition slip are examined to ensure that the ABO and Rh types are compatible. The expiration date is also checked, and the product is inspected for discoloration, gas bubbles, or cloudiness—indicators of bacterial growth or hemolysis.
TRANSFUSION RESPONSIBILITIES The nurse takes the vital signs, including temperature, immediately before initiating the transfusion. Infusion begins slowly. A nurse remains with the client for the first 15 to 30 minutes. Any severe reaction usually occurs with administration of the first 50 mL of blood. The nurse assesses vital signs 15 minutes after initiation of the transfusion to detect signs of a reaction. If there are none, the infusion rate can be increased to transfuse 1 unit in about 2 hours (depending on the client’s cardiovascular status). The nurse takes the vital signs every hour throughout the transfusion or as specified by agency policy. Blood components without large amounts of red blood cells (RBCs) can be infused more quickly. The identification checks are the same as for RBC transfusions. Physiologic changes in older clients may necessitate that blood products be transfused at a slower rate. Best practices related to the nursing care needs of older clients undergoing transfusion therapy are provided in Chart 40-16.
TYPES OF TRANSFUSIONS
Red Blood Cell Transfusions RBCs are administered to replace erythrocytes lost as a result of trauma or surgical interventions. Clients with clinical conditions that result in the destruction or abnormal maturation of RBCs may also benefit from RBC transfusions. Packed RBCs, supplied in 250-mL bags, are a concentrated source of RBCs and are the most common component administered to RBCdeficient clients (Dreger & Tremback, 1998). Packed RBCs are administered to individuals with a hemoglobin concentration less than 6 g/dL (or a hemoglobin value of 6 to 10 g/dL if clinical symptoms are present) (Kennedy, 1999). Blood transfusions are actually transplantations of tissue from one person to another. The donor and recipient blood must thus be carefully checked for compatibility to prevent potentially lethal reactions (Table 40-7).
Compatibility is determined by two different types of antigen systems (cell surface proteins): the ABO system antigens and the Rh antigen, present on the membrane surface of RBCs (Dreger & Tremback, 1998). RBC antigens are inherited.
For the ABO antigen system, a person inherits one of the following:
• A antigen (type A blood)
• B antigen (type B blood)
• Both A and B antigens (type AB blood)
• No antigens (type O blood)
Within the first few years of a child’s life, circulating antibodies develop against the blood type antigens that were not inherited. For example, a child with type A blood will form antigens against type B blood. A child with type O blood has not inherited either A or B antigens and will form antibodies against RBCs that contain either A or B antigens. If erythrocytes that contain a foreign antigen are infused into a recipient, the donated tissue can be recognized by the immune system of the recipient as non-self, and the client may have a reaction to the transfused products. The mechanism of the Rh antigen system is slightly different. An Rh-negative person is born without the antigen and does not form antibodies unless he or she is specifically sensitized to it. Sensitization can occur with RBC transfusions from an Rh-positive person or from exposure during pregnancy and birth. Once an Rh-negative person has been sensitized and antibody development has occurred, any exposure to Rh-positive blood can cause a transfusion reaction. Antibody development can be prevented by administration of Rh-immune globulin as soon as exposure to the Rh antigen is suspected. People who have Rh-positive blood can receive an RBC transfusion from an Rh-negative donor, but Rh-negative people must never receive Rh-positive blood.
Platelet Transfusions Platelets are administered to clients with platelet counts below 20,000 mm3 and to clients with thrombocytopenia who are actively bleeding or are scheduled for an invasive procedure (Dreger, & Tremback, 1998). Platelet transfusions are usually pooled from as many as 10 donors and do not have to be of the same blood type as the client. For clients who are candidates for bone marrow transplantation (BMT) or who require multiple platelet transfusions, single-donor platelets may be ordered. Single-donor platelets are obtained from one person and decrease the amount of antigen exposure to the recipient, helping prevent the formation of platelet antibodies. The chances of allergic transfusion reactions to future platelet transfusions are thus reduced. Platelet infusion bags usually contain 300 mL for pooled platelets and 200 mL for single-donor platelets. Because the platelet is a fragile cell, platelet transfusions are administered rapidly after being brought to the client’s room, usually over a 15- to 30-minute period. A special transfusion set with a smaller filter and shorter tubing is used. Standard transfusion sets are not used with platelets because the filter traps the platelets, and the longer tubing increases platelet adherence to the lumen. Additional platelet filters help remove white blood cells (WBCs) in the platelet concentrate. These filters are connected directly to the platelet transfusion set and are used for clients who have a history of febrile reactions or who will require multiple platelet transfusions. The nurse takes the vital signs before the infusion, 15 minutes after the infusion is initiated, and at its completion. The client may be premedicated with meperidine (Demerol) or hydrocortisone to minimize the chances of a reaction. He or she can become febrile and experience rigors (severe chills) during transfusion, but these symptoms are not considered a true transfusion reaction. IV administration of amphotericin B (Amphotec, Fungizone), an antifungal agent given to many clients with leukemia, is discontinued during platelet transfusion and not resumed for at least 1 hour after transfusion. Amphotericin B can cause severe allergic reactions that are difficult to distinguish from transfusion reactions.
Plasma Transfusions
Historically, plasma infusions have been administered to replace blood volume, and they are occasionally still used for this purpose. It is more common for plasma to be frozen immediately after donation. Freezing preserves the clotting factors, and the plasma can then be used for clients with clotting disorders (Kennedy, 1999).
Fresh frozen plasma (FFP) is infused immediately after thawing while the clotting factors are still viable. Clients who are actively bleeding with a prothrombin time (PT) or partial thromboplastin time (FIT) greater than 1.5 times normal are candidates for an FFP infusion (Harrahill & DeLoughery, 1998). ABO compatibility is required for transfusion of plasma products. The volume of the infusion bag is approximately 200 mL. The infusion takes place as rapidly as the client can tolerate, generally over a 30- to 60-minute period, through a regular Y-set or straight-filtered tubing.
Cryoprecipitate is a product derived from plasma. Clotting factors VIII and XIII, von Willebrand’s factor, fibronectin, and fibrinogen are precipitated from pooled plasma to produce cryoprecipitate. Clients with a fibrinogen level less than 100 mg/dL are candidates for a cryoprecipitate infusion (Harrahill & DeLoughery, 1998). This highly concentrated blood product is administered to clients with clotting factor disorders at a volume of 10 to 15 mL/unit. Although cryoprecipitate can be infused, it is usually given by IV push within 3 minutes. Dosages are individualized, and it is best if the cryoprecipitate is ABO compatible.
Granulocyte Transfusions At some centers, neutropenic clients with infections receive granulocyte transfusions for WBC replacement. However, this practice is highly controversial because the potential benefit to the client must be weighed against the potential severe reactions that often accompany granulocyte transfusions. The surfaces of granulocytes contaiumerous antigens that can cause severe antibody-antigen reactions when infused into a recipient whose immune system recognizes these antigens as non-self. In addition, transfused granulocytes have a very short life span and are probably of minimal benefit to the client (see Chapter 20). There is some evidence that treatment with antibiotics alone results in better survival rates. Granulocytes are suspended in 400 mL of plasma and should be transfused over a 45- to 60- minute period. Institutional policies often require more stringent monitoring of clients receiving granulocytes. A physician may need to be present in the hospital unit, and vital signs may need to be taken every 15 minutes throughout the transfusion. Administration of amphotericin B and granulocyte transfusions should be separated by 4 to 6 hours.
TRANSFUSION REACTIONS Clients can experience any of the following transfusion reactions: hemolytic, allergic, febrile, or bacterial reactions; circulatory overload; or transfusion-associated graft-versus-host disease (GVHD). The nurse is vigilant to prevent serious complications through early detection and initiation of appropriate treatment.
Hemolytic Transfusion Reactions Hemolytic transfusion reactions are caused by blood type or Rh incompatibility. When blood containing antibodies against the recipient’s blood is infused, antigen-antibody complexes are formed and released into the circulation. These complexes can destroy the transfused cells and initiate inflammatory responses in the recipient’s blood vessel walls and organs. The ensuing reaction may be mild, with fever and chills, or life threatening, with disseminated intravascular coagulation (DIC) and circulatory collapse (Robb, 1999).
Other clinical signs include the following:
• Apprehension
• Headache
• Chest pain
• Low back pain
• Tachycardia
• Tachypnea.
• Hypotension
• Hemoglobinuria
• A sense of impending doom
The onset of a hemolytic transfusion reaction may be immediate or may not occur until subsequent units have been transfused.
Allergic Transfusion Reactions Allergic transfusion reactions are most often seen in clients with a history of allergy. They may have urticaria, itching, bronchospasm, or occasionally anaphylaxis. Onset of this type of reaction usually occurs during or up to 24 hours after the transfusion. Clients with a history of allergy can be given buffy coat-poor or washed red blood cells (RBCs) in which the white blood cells (WBCs) and plasma have been removed. This procedure minimizes the possibility of an allergic reaction.
Febrile Transfusion Reactions Febrile transfusion reactions occur most commonly in the client with anti-WBC antibodies, a situation seen after multiple transfusions. The recipient experiences the following: • Sensations of cold • Tachycardia • Fever • Hypotension • Tachypnea Again, the physician can order buffy coat-poor RBCs or single-donor HLA-matched platelets. Leukocyte filters may also be used to trap WBCs and prevent their transfusion into the client.
Bacterial Transfusion Reactions Bacterial transfusion reactions are seen after transfusion of contaminated blood products. Usually a gram-negative organism is the source because these bacteria grow rapidly in blood stored under refrigeration. Symptoms include the following: • Tachycardia • Hypotension • Fever • Chills • Shock The onset of a bacterial transfusion reaction is rapid.
Circulatory Overload Circulatory overload can occur when a blood product is administered too quickly (Goldy, 1998). This complication is most common with whole-blood transfusions or when the client requires multiple transfusions. Older adults are most at risk for this condition (see Chart 40-16). Symptoms include the following: • Hypertension • Bounding pulse • Distended jugular veins • Dyspnea • Restlessness • Confusion The nurse can both manage and prevent this complication by monitoring intake and output, transfusing blood products more slowly, and administering diuretics.
Transfusion-Associated Graft-Versus-Host Disease Transfusion-associated graft-versus-host disease (TA-GVHD) is an infrequent but life-threatening complication that can occur in both immunosuppressed and immunocompetent clients. Its cause in immunosuppressed clients is similar to that of GVHD associated with allogeneic bone marrow transplantation (BMT), discussed on p.
AUTOLOGOUS BLOOD TRANSFUSIONS Autologous blood transfusions involve collection and transfusion of the client’s own blood. Advantages of this type of transfusion are guaranteed compatibility and elimination of the risk of transmitting diseases such as hepatitis or HIV. The four types of autologous blood transfusions are preoperative autologous blood donation, acute normovolemic hemodilution, intraoperative autologous transfusion, and postoperative blood salvage. Preoperative autologous blood donation, the most common type of autologous blood transfusion, involves collection of whole blood from the client, division into components, and then storage for later use (such as after a scheduled surgical procedure).
As long as hematocrit and hemoglobin levels are within a safe range, the client can donate blood on a weekly basis until the prescribed amount of blood is obtained. Fresh packed RBCs may be stored for 42 days. For individuals with rare blood types, blood may be frozen for up to 10 years. Platelets and plasma may be collected via pheresis. Some cardiovascular problems and bacteremia are contraindications for autologous blood donation. Acute normovolemic hemodilution involves withdrawal of a client’s RBCs and volume replacement just before a surgical procedure. The goal is to decrease RBC loss during surgery. The blood is stored at room temperature for up to 6 hours and reinfused after surgery. This type of autologous transfusion is appropriate for healthy clients but is contraindicated for individuals who are anemic or who have poor renal function. Intraoperative autologous transfusion and postoperative blood salvage involve the recovery and reinfusion of a client’s own blood, collected either from an operative field or postoperatively from a wound.
Several commercial products are available that collect, filter, and drain the blood into a transfusion bag. This autologous blood is often used for trauma or surgical clients with severe blood loss and must be reinfused within 6 hours. The nurse transfuses autologous blood products using the guidelines previously described. Although the client receiving autologous blood is not at risk for most types of transfusion reactions, the nurse must still assess for circulatory overload or bacterial transfusion reactions that can occur as a result of contamination
