Assessment of the Renal/Urinary System
The renal system includes the kidneys and the entire urinary tract. The ureters, bladder, and urethra provide a drainage route for the excretion of urine. Structural or functional problems in the kidney or urinary tract usually alter fluid, electrolyte, and acid-base balance.
Assessment of the client at risk for or with actual problems of the renal system begins with a history and physical assessment. A clear understanding of the anatomy, physiology, and diagnostic tests of the renal system will help the nurse in problem solving about renal function in the clinical setting. It will also assist the nurse in teaching the client about the purpose of tests or procedures and in physically and emotionally preparing the client for assessment.
Kidneys
■ Structure
GROSS ANATOMY
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Normally, two kidneys are located in the retroperitoneal space (behind the peritoneum, not really in the abdominal cavity), one on either side of the vertebral column . The adult kidney is 4 to
Fig. Renal anatomny
The kidneys receive 20% to 25% of the total cardiac output. Renal blood flow per minute varies from about 600 to 1300 mL/min. The blood supply to each kidney is usually delivered by a single renal artery, which branches from the abdominal aorta (Table 69-1). The renal artery separates into progressively smaller arteries, supplying all areas of the renal tissue (parenchyma) and the nephrons. The smallest arteries, the afferent arterioles, feed the nephrons directly to form urine. Venous blood from the kidneys starts with the capillaries surrounding each nephron. These capillaries drain into progressively larger veins, with blood eventually returned to the inferior vena cava through the renal vein.
■ MICROSCOPIC ANATOMY
The nephron is the functional unit of the kidney, and it is here that urine is actually formed from blood. There are about 1 million nephrons per kidney, and each nephron separately makes urine from blood.
There are two types of nephrons: cortical nephrons and juxtamedullary nephrons. The cortical nephrons are short, with all parts located in the renal cortex.
THE SEQUENCE OF RENAL BLOOD FLOW FROM THE RENAL ARTERY TO THE RENAL VEIN
1. Renal artery
2.Interlobar artery
3.Arcuate artery
4.Interlobular artery
5.Afferent arteriole
6.Glomerulus
7.Efferent arteriole
8.Peritubular capillaries or vasa recta
9.Stellate vein
10.Interlobular vein
11.Arcuate vein
12.Interlobar vein
13.Renal vein
Fig. Arcuate vein and artery
The juxtamedullary nephrons (about 20% of all nephrons) are longer, and their tubes and associated blood vessels dip deeply into the medulla. The purpose of the juxtamedullary nephrons is to concentrate urine during times of low fluid intake. The ability to concentrate urine allows for the maximum excretion of waste products with less fluid loss.
Blood supply to the nephron is delivered via the afferent arteriole, the smallest, most distal portion of the renal arterial system. From the afferent arteriole, blood flows into the glomerulus, a series of specialized capillary loops. It is through these capillaries that water and small particles are filtered from the blood to make urine. The remaining blood exits the glomerulus via the efferent arteriole. From the efferent arteriole, blood exits into one of two additional capillary systems:
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• The peritubular capillaries around the tubular component of cortical nephrons
Fig. Renal anatomy
Each nephron is a tubular structure with distinct parts (Figure 69-3). The tubular component of the nephron begins with Bowman’s capsule, a saclike structure that surrounds the glomerulus. The tubular tissue of Bowman’s capsule narrows into the proximal convoluted tubule (PCT). The PCT twists and turns, finally straightening into the descending limb of the loop of Henle. The descending loop of Henle dips in the direction of the medulla but forms a hairpin loop and comes back up into the cortex.
As the loop of Henle changes direction, two segments are identified in the ascending limb of the loop of Henle: the thin and thick segments. The distal convoluted tubule (DCT) is formed from the thick segment of the ascending limb of the loop of Henle. The DCT ends in one of many collecting ducts located in the kidney tissue. The urine in the collecting ducts passes through the papillae and empties into the renal pelvis.
A series of specialized cells located in the afferent arteriole, efferent arteriole, and DCT are collectively known as the jux-taglomerular complex (Figure 69-4). The specialized cells in this area are the renin-producing cells, which produce and store renin. Renin is a hormone that helps to regulate blood flow, glomerular filtration rate (GFR), and systemic blood pressure. Renin is secreted when special cells in the DCT called the macula densa sense changes in blood volume and pressure. The macula densa lies next to the renin-producing granular cells of both afferent and efferent arterioles. Renin is secreted when the macula densa cells sense that blood volume, blood pressure, or blood sodium levels are low. Renin then converts angiotensinogen into angiotensin I. This leads to a series of reactions that cause secretion of the hormone aldosterone (Figure 69-5). Aldosterone increases kidney reabsorption of sodium and water, restoring blood pressure, blood volume, and blood sodium levels. (See Chapter 11 for a more complete description of the renin-angiotensin-aldosterone pathway).
Microscopically, the glomerular capillary wall has three layers (Figure 69-6): the endothelium, the basement membrane, and the epithelium. The endothelial and epithelial cells lining the glomerular capillary are separated by pores that filter water and small particles from the blood into Bowman’s capsule. This fluid is called the filtrate, or early urine.
Function
The kidneys have both regulatory and hormonal functions. The regulatory functions control fluid, electrolyte, and acid-base balance. The hormonal functions control red blood cell formation, blood pressure, and vitamin D activation.
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REGULATORY FUNCTIONS
Fig. Anatomy of the nephron, the functional unit of the kidney.
Note that the particular nephron labeled here is a juxtamedullary nephron.
These processes occur through filtration, diffusion, active transport, and osmosis.
GLOMERULAR FILTRATION.
Glomerular filtration is the first process in urine formation. As blood passes from the afferent arteriole into the glomerulus, water, electrolytes, and other particles (e.g., creatinine, urea nitrogen, and glucose) are filtered across the glomerular membrane into Bowman’s capsule to form glomerular filtrate. As the filtrate enters the proximal convoluted tubule (PCT), it is called tubular filtrate.
Large-molecular weight substances (>69,000 daltons), such as albumin and globulin, are too large to filter through the glomerular capillary walls. Red blood cells (RBCs) also are too large to pass from the arterioles into the filtrate. Therefore these substances are not normally present in the filtrate or in the final urine.
Approximately
The GFR is related to blood pressure and blood flow. The ability of the kidneys to self-regulate renal blood pressure and renal blood flow keeps GFR constant. GFR is controlled by selectively constricting and dilating the afferent and efferent arterioles. When the afferent arteriole is constricted and/or the efferent arteriole is dilated, pressure in the glomerular capillaries falls and filtration decreases. When the afferent arteriole is dilated and/or the efferent arteriole is constricted, pressure in the glomerular capillaries rises and filtration increases. Through this self-regulation the kidney can maintain a constant GFR, even when systemic blood pressure changes. When systolic blood pressure drops below about
TUBULAR REABSORPTION. Tubular reabsorption is the second process involved in urine formation. It is the tubular reabsorption of most of the filtrate that keeps normal urine output at 1 to 3 L/day and prevents dehydration. As the filtrate passes through the tubular component of the nephron, the kidney reabsorbs variable amounts of water and electrolytes. Reabsorption returns particles (solutes) and water to the blood.
Fig. Glomerular filtration
VASCULAR COMPONENTS
Afferent arteriole
Glomerulus
Efferent arteriole
Peritubular capillaries (PTCs) and vasa recta (VR)
Delivers arterial blood from the branches of the renal artery into the glomerulus
Capillary loops with thin semipermeable membrane
Delivers arterial blood from the glomerulus into the peritubular capillaries or the vasa recta
PTCs: surround tubular components of cortical nephrons
VR: surround tubular components of juxtamedullary nephrons
Autoregulation of renal blood flow via vasoconstriction or vasodilation Renin-producing granular cells
Site of glomerular filtration
Glomerular filtration occurs when hydrostatic pressure (blood pressure) is greater than opposing forces (tubular filtrate and on-cotic pressure)
Autoregulation of renal blood flow via vasoconstriction or vasodilation Renin-producing granular cells
Tubular reabsorption and tubular secretion allow movement of water and solutes to or from the tubules, interstitium, and blood
TUBULAR COMPONENTS
Bowman’s capsule (ВС)
Proximal convoluted tubule (PCT)
Loop of Henle Descending limb (DL)
Ascending limb (
Distal convoluted tubule (DCT)
Collecting ducts
Thin membranous sac surrounding V8 of the glomerulus
Evolves from and is continuous with Bowman’s capsule
Specialized cellular lining facilitates tubular reabsorption
Continues from PCT
Juxtamedullary nephrons dip deep into the medulla
Permeable to water, urea, and sodium chloride Emerges from DL as it turns and is redirected up toward the renal cortex
Evolves from
Collects formed urine from several tubules and delivers it into the renal pelvis
Collects glomerular filtrate (GF) and funnels GF into the tubule
Site for reabsorption of sodium, chloride, water, glucose, amino acids, potassium, calcium, bicarbonate, phosphate, and urea
Regulation of water balance
Potassium and magnesium reabsorption in
the thick segment Thin segment is impermeable to water
Site of additional water and electrolyte reabsorption, including bicarbonate Potassium and hydrogen secretion
Fig. Sodium and water reabsorption by the tubules of a cortical nephron.
Reabsorption occurs from the filtrate across the tubular lumen of the nephron and into the blood of the peritubular capillaries. The PCT reabsorbs approximately 65% of the total glomerular filtrate.
WATER REABSORPTION. The tubules reabsorb more than 99% of all filtered water back into the body (Figure 69-8). Most water reabsorption from the filtrate into the plasma occurs as the filtrate passes through the PCT. Water reabsorption continues as the filtrate flows down the descending loop of Henle. The thin segment of the ascending loop of Henle is not permeable to water.
The distal convoluted tubule (DCT) is potentially permeable to water, and therefore water reabsorption can occur as the filtrate continues to flow through the tubule. The membrane of the DCT may be made more permeable to water through the influence of the hormones antidiuretic hormone (ADH) and aldosterone. ADH increases the permeability of the membrane to water and enhances water reabsorption. Aldosterone promotes the reabsorption of sodium in the DCT; water reabsorption occurs as a result of the movement of sodium (where sodium goes, water follows).
The ability of the kidneys to vary the volume or concentration of urine helps regulate total water balance regardless of water intake. In this way, the healthy kidney can prevent dehydration when fluid intake is low and prevent circulatory overload when fluid intake is excessive.
SOLUTE REABSORPTION. Some particles in the tubular filtrate are returned to the blood. This process is called tubular reabsorption. About 50% of all urea present in the glomerular filtrate is reabsorbed, but virtually no creatinine is reabsorbed.
Most sodium, chloride, and water reabsorption occurs in the PCT. The collecting ducts are the other major site of sodium, chloride, and water reabsorption, which usually occurs under the stimulation of aldosterone. Potassium is also primarily reabsorbed in the PCT, with 20% to 40% of potassium reabsorption occurring in the thick segment of the ascending loop of Henle.
Bicarbonate, calcium, and phosphate are reabsorbed in the PCT, with a little additional reabsorption occurring in the ascending loop of Henle and the DCT. The reabsorption of bicarbonate helps neutralize acids and maintain a normal blood pH. Calcium reabsorption and excretion is controlled by circulating calcitonin and parathyroid hormone (PTH) levels.
The kidney reabsorbs some of the glucose filtered from the blood. However, there is a limit to how much glucose the kidney can reabsorb. This limit is called the renal threshold for glucose reabsorption or the transport maximum for glucose reabsorption. The usual renal threshold for glucose is about 220 mg/dL. This means that at a blood glucose level of 220 mg/dL, all glucose is reabsorbed from the filtrate and returned to the blood. When blood glucose levels are greater than 220 mg/dL, some glucose stays in the filtrate and is present in the urine. Normally, almost all glucose and any filtered amino acids or proteins are reabsorbed.
TUBULAR SECRETION. Tubular secretion is a third process involved in urine formation. Like glomerular filtration, it is a process by which substances may move from the blood into the tubular filtrate. During tubular secretion, molecules pass from the peritubular capillaries, across capillary membranes, and into the cells that line the tubules. From the cells these substances are moved into the urine to be excreted from the body. Potassium (K+) and hydrogen ions (H+) are some of the substances moved in this way to maintain homeo-stasis of electrolytes and pH.
HORMONAL FUNCTIONS
The kidneys produce renin, prostaglandins, bradykinin, eryth-ropoietin, and activated vitamin D. Other secretions, such as the kinins, influence renal blood flow and capillary permeability. The kidneys also have a role in the breakdown and excretion of insulin.
RENIN PRODUCTION. As discussed earlier under Microscopic Anatomy (pp. 1590 and 1591), renin assists in the regulation of blood pressure. Renin is formed and released when there is a decrease in blood flow, volume, or pressure through the renal arterioles or when a decrease in the sodium ion concentration of the tubular filtrate is detected through the receptors of the juxtaglomerular complex.
Raise blood pressure as result of angiotensin (local vasocon-striction) and aldosterone (volume expansion) secretion
Regulate intrarenal blood flow by vasodilation or vasoconstriction Increases blood flow (vasodilation) and vascular permeability Stimulates bone marrow to make red blood cells Promotes absorption of calcium in the gastrointestinal tract/. Makes DCT and CD permeable to water to maximize reabsorp-tion and produce a concentrated urine. Promotes sodium reabsorption and potassium secretion in DCT and CD; water and chloride follow sodium movement
Cause tubular secretion of sodium. The release of renin stimulates the production of angiotensin II through a series of metabolic steps (see Figure 69-5). Angiotensin II increases systemic blood pressure through powerful vasoconstrictive effects and stimulates the release of aldosterone from the adrenal cortex. Aldosterone increases the reabsorption of sodium in the distal tubule of the nephron. Therefore more water is reabsorbed and blood pressure is increased because of increases in blood volume expansion. When renal blood flow is diminished, this renin-angiotensin-aldosterone system of blood pressure regulation influences the autoregulatory blood pressure processes within the nephron as well as systemic blood pressure.
PROSTAGLANDIN PRODUCTION. Prostaglandins are produced in a variety of tissues, including the kidney. Specific prostaglandins produced in the kidney are prostaglandin E2 (PGE2) and prostacyclin (PGI2). These prostaglandins help regulate glomerular filtration, kidney vascular resistance, and renin production. PGE2 acts on the distal tubule and collecting duct to inhibit ADH secretion, decrease membrane permeability, and promote sodium and water excretion.
BRADYKININ PRODUCTION. The presence of angiotensin II, prostaglandins, and ADH stimulates the release of bradykinin in the renal system. Bradykinin dilates the afferent arteriole and increases capillary membrane permeability to some solutes. These actions maintain kidney blood flow and tubular function even when other conditions cause systemic vasoconstriction.
ERYTHROPOIETIN PRODUCTION. Erythropoietin
is produced and released in response to decreased oxygen tension in the renal blood supply. Erythropoietin stimulates red blood cell (RBC) production in the bone marrow. When kidney tissue is destroyed or nonfunctional, erythropoietin production decreases and the person becomes anemic.
VITAMIN D ACTIVATION. A series of metabolic changes are necessary for vitamin D, a hormone, to become active. Metabolic conversions take place in the skin through exposure to ultraviolet light and then in the liver. From there, vitamin D is converted to its active form (1,25-dihydroxy-cholecalciferol) in the kidney. Activated vitamin D is necessary to absorb calcium in the gastrointestinal tract and is critical in the regulation of calcium balance.
Ureters
Structure
Each kidney has a single ureter, a hollow tubelike structure that connects the renal pelvis with the urinary bladder. The ureter is about !/2 inch (
The diameter of the ureter narrows in three areas: In the upper third of the ureter, at the point at which the renal pelvis becomes the ureter, is a narrowing known as the ureteropelvic junction (UPJ).
■The ureter also narrows as it arches toward the abdominal wall (aortoiliac bend).
■Each ureter thearrows upon entering the posterior wall of the urinary bladder at an oblique angle; this point is referred to as the ureterovesical junction (UVJ).
The ureter tunnels through bladder tissue for a few centimeters before opening into the bladder in an area referred to as the trigone.
The ureter is composed of three layers: an inner lining of mucous membrane (urothelium), a middle layer of smooth muscle fibers, and an outer layer of fibrous tissue. The outer layer of the ureter contains the blood supply. The middle layer of ureteral tissue contains longitudinal and circular muscle fibers. These muscle fibers are under the control of a variety of nerve pathways from the lower spinal cord.
Function
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Rapid peristaltic contractions of the smooth muscle in the ureter move urine from the renal pelvis of the kidney to the bladder. Stretch receptors in the renal pelvis regulate ureteral peristalsis. For example, a large volume of urine in the renal pelvis stimulates the stretch receptors, which respond by causing an increase in ureteral peristalsis.
Fig. Gross anatomy of the urinary bladder.
Urinary Bladder
■ Structure
The urinary bladder is a muscular sac. The upper surface lies next to the peritoneal cavity. In men, the bladder is in front of the rectum. In women, the bladder is in front of the vagina. The bladder lies directly behind the pubic symphysis, the connecting point for pelvic bone structures.
The bladder is composed of the body (the rounded sac portion) and the bladder neck (posterior urethra), which connects to the bladder body. The bladder has three linings, an inner lining of epithelial cells (urothelium), middle layers of smooth muscle (detrusor muscle), and an outer lining. The trigone is an area on the inner aspect of the posterior bladder wall between the points of ureteral entry (ureterovesical junctions [UVJs]) and the urethra.
The internal urethral sphincter is composed of the smooth detrusor muscle of the bladder neck and elastic tissue. The external urethral sphincter is composed of skeletal muscle that surrounds the urethra. In men, the external sphincter surrounds the urethra at the base of the prostate gland. In women, the external sphincter is at the base of the bladder. The pudendal nerve from the spinal cord controls the external sphincter.
■ Function
The urinary bladder is a site for the temporary storage of urine. The bladder also provides continence and enables micturition (voiding). The secretions of the bladder lining resist bacteria.
Bladder continence is achieved during filling through the combination of detrusor muscle relaxation, internal sphincter muscle tone, and external sphincter contraction. As the bladder fills with urine, stretch sensations are transmitted to segments of spinal sacral nerves S2 and S3.
■ MAINTAINING CONTINENCE
Continence is maintained by the interaction of the nerves that control the muscles of the bladder, bladder neck, urethra, the pelvic floor, as well as by factors that close the urethra. During bladder filling, the sympathetic nervous system fibers prevent detrusor muscle contraction. These control centers are located in the cerebral cortex, the brainstem, and the sacral part of the spinal cord. For urethral closure to be adequate for continence, the mucosal surfaces must be in contact and must be adhesive. Contact depends on the structural and functional integrity of the involved nerves and muscles. Adhesion depends on the adequate secretion of mucus-like substances.
Micturition (voiding) is a reflex of parasympathetic control that stimulates contraction of the detrusor muscle at the same time as relaxation of the external sphincter and the muscles of the pelvic floor. With detrusor muscle contraction, the UVJ of the ureter closes, and the normally round bladder assumes the shape of a funnel. Voiding is a voluntary act as the result of a learned response and is controlled by the cerebral cortex and the brainstem. Contraction of the external sphincter inhibits the micturition reflex and prevents voiding.
Urethra
■ Structure
The urethra is a narrow, tubelike structure lined with mucous membranes and epithelial cells. The urethral meatus, or opening, is the terminal point of the urethra. In men, the urethra is about 6 to
The prostatic urethra, which traverses the prostate gland from the urinary bladder
The membranous urethra, which traverses the wall of the pelvic floor
The cavernous urethra, which is external and extends through the length of the penis
In women, the urethra is about 1 to
Function
The urethra is a tube for eliminating urine from the body. The passing of urine normally removes bacteria from the urethra.
Renal/Urinary System Changes Associated with Aging
■ Renal Changes
Structural and functional changes occur in the kidney as a result of the aging process. These changes often have clinical significance. The kidney loses cortical mass and gets smaller by 80 years of age. This cortical loss is caused by reduced re-
Physiologic Change
Decreased glomerular filtration rate (GFR) Nocturia Decreased bladder capacity Weakened urinary sphincter muscles and shortened urethra in women Tendency to retain urine
Nursing Implications
Monitor hydration status. Ensure adequate fluid intake.
Administer potentially nephrotoxic agents or medications carefully.
Ensure adequate nighttime lighting and a hazard-free environment.
Ensure the availability of a toilet, bedpan, or urinal.
Discourage excessive fluid intake for 2-4 hr before the client retires for the evening.
Encourage the client to use the toilet, bedpan, or urinal at least q2h.
Respond as soon as possible to the client’s indication of the need to void.
Respond as soon as possible to the client’s indication of the need to void.
Provide thorough perineal care after each voiding.
Observe the client for urinary retention (e.g., bladder distention) or urinary tract infection (e.g., dys-uria, foul odor, confusion).
Provide privacy, assistance, and voiding stimulants such as warm water over the perineum as needed.
Rationale
With aging, the ability of the kidneys to regulate water balance is decreased. The kidneys are less able to conserve water when necessary. Dehydration results in decreased renal blood flow and increases the nephrotoxic potential of many agents. Acute or chronic renal failure may result.
Nocturia may occur from decreased renal concentrating ability associated with aging. The desire to maintain continence prompts individuals to seek the bathroom. Falls and injuries are common among older clients seeking bathroom facilities. Excessive fluid intake at nighttime may increase nocturia.
By emptying the bladder on a regular basis, urinary incontinence from overflow may be avoided. A quick response may alleviate episodes of urinary stress incontinence. The shortened urethra increases the potential for bladder infections. Good perineal hygiene may prevent skin irritations and urinary tract infection (UTI). Urinary stasis may result in a UTI. UTIs may become bloodstream infections, resulting in sep-ticemia or septic shock.
Nursing interventions can help to initiate voiding.
The medulla appears not to be affected by aging, and the juxtamedullary nephrons are generally preserved. However, the glomerular and tubular basement membranes thicken, reducing filtrating ability. Both the number of glomerali and their surface area decrease with aging. The length of the tubules also decreases.
Kidney function also changes with aging (Chart 69-1). Blood flow to the kidney decreases by about 10% per decade as blood vessels thicken and become more rigid. Glomerular filtration rate (GFR) decreases with advancing age and more rapidly after 45 years of age. By age 65 years, the GFR decreases to approximately 65 mL/min (roughly half the rate in a young adult). This decline is more rapid in clients with diabetes or hypertension.
Tubular changes with aging are shown by a decreased ability to concentrate urine, resulting in nocturia (increased need to urinate at night). The excretion and regulation of sodium, acids, and bicarbonate remain effective but are less efficient because homeostasis is slower. Along with an age-related impairment in the thirst mechanism, these changes may be associated with an increased incidence of dehydration and hypernatremia (increased blood sodium levels) in the older adult (Brenner, 2000). Hormonal changes include a decrease in renin secretion, aldosterone levels, and activation of vitamin D.
CULTURAL CONSIDERATIONS
^H^ African Americans experience more rapid age-related decreases in GFR than do Caucasians (Brenner, 2000). The renal excretion of sodium is less effective in hypertensive African Americans who have high sodium intake, and the kidneys have approximately 20% less blood flow as a result of anatomic changes in small renal vessels (Shulman & Hall, 1991).
■ Urinary Changes
Changes in the elasticity of the detrusor muscle may cause decreased bladder capacity and a decreased ability to retain urine. The sensation of the urge to void may cause immediate bladder emptying because the urinary sphincters lose muscle tone and often become weaker with age. In women, weakening muscles shorten the urethra, which contributes to incontinence. In men, an enlarged prostate gland causes difficulty in starting the urine stream and may cause urinary retention.
One way to assess renal and urologic function is to use Gordon’s Functional Health Patterns (Gordon, 2000). The patterns most pertinent to the renal system are Nutritional/ Metabolic and Elimination .
■ DEMOGRAPHIC DATA
Age, gender, race, and ethnicity are important in the overall history of the client with suspected renal or urinary dysfunction. A sudden onset of hypertension in clients older than 50 years of age suggests possible kidney disease. Clinical evidence of adult polycystic kidney disease typically occurs in clients in their 40s or 50s. In men older than 50 years, altered urine patterns suggest prostatic disease.
Anatomic gender differences make some disorders worse or more common. For example, men rarely have urinary tract infections unless there are abnormalities, such as ureteral reflux or prostatic enlargement. Women have a shorter urethra and therefore more commonly experience cystitis (bladder infection) because bacteria pass more readily into the bladder.
CULTURAL CONSIDERATIONS
^ End-stage renal disease (ESRD) is three to four times more common in African Americans, Native Americans, and Mexican Americans than in Caucasians. A history of hypertension or diabetes mellitus (both associated with renal disease) is also common in these groups.
PERSONAL AND FAMILY HISTORY
The family history of the client with a suspected kidney or urologic problem is significant because some disorders have a familial inheritance pattern. The client is asked whether his or her siblings, parents, parents’ siblings, or grandparents have had renal problems. Past terms used for kidney disease include Bright’s disease, nephritis, and nephrosis. Clients may use these terms to describe kidney disease as it was known by their parents or grandparents in the earlier part of the twentieth century. Adult polycystic kidney disease can occur in clients of either gender.
The client is asked about any previous renal or urologic disorders, including tumors, infections, stones, or urologic surgery. A history of any chronic health problems, such as diabetes mellitus or hypertension, may contribute to the development of renal disease.
The nurse identifies all of the client’s prescription medications. The client is asked about their duration of use and whether any recent changes in medications have been prescribed. Drugs prescribed for diabetes mellitus, hypertension, cardiac disorders, hormonal disorders, cancer, arthritis, and psychiatric disorders are potential causes of renal dysfunction. Antibiotics taken for infections, such as gentamicin (Garamycin, Cidomycin^), may also produce sudden renal dysfunction.
The use of over-the-counter (OTC) drugs or agents, including vitamin and mineral supplements and replacements, laxatives, analgesics, and nonsteroidal anti-inflammatory drugs (NS AIDs) is explored. Many of these drugs affect renal
Nutritional/Metabolic Pattern
What is your typical daily food intake? Describe a day’s meals, snacks, and vitamins. How much salt do you typically add to your food? Do you
use salt substitutes? How is your appetite?
Have you experienced any nausea or vomiting? What is your typical daily fluid intake? What types of fluids do you drink (water, juices, soft drinks,
coffee, tea)?
How much fluid do you drink each day? Have you had any recent change in your weight? Weight gain? Weight loss? How much? Have you noticed a change in the tightness of your rings or shoes? Tighter? Looser? Have you noticed any skin changes lately? More dry? Less
Dry? Itchy?
Elimination Pattern
What is your usual bowel elimination pattern? Frequency?
Character? Discomfort? Laxatives? What is your usual urinary elimination pattern? Frequency?
Amount? Color? Odor? Control? Have you noticed a change in the amount of urine? Do you have any problem with excessive perspiration? Do you have any other type of drainage?
Based on Gordon, M. (2000). Manual of nursing diagnosis (9th ed.).
function. The long-term use of NSAIDs, especially combination agents, can seriously reduce renal function.
The client is specifically asked whether he or she has ever been told about the presence of protein or albumin in the urine. The question “Have you ever been told that your blood pressure is high?” may prompt a vastly different response than “Do you have high blood pressure?” The nurse also asks female clients about health problems associated with pregnancy (e.g., proteinuria, high blood pressure, gestational diabetes, and urinary tract infections). Additional information is obtained about the following:
• Chemical or environmental toxin exposure in occupational or other settings
• Recent travel to geographic regions that pose infectious isease risks
• Recent physical injuries
• Trauma
• Sexual contacts
• A history of altered patterns of urinary elimination
DIET HISTORY
The client with known or suspected renal or urologic disorders is asked about his or her usual diet and any recent changes in the diet. The excessive intake or omission of certain categories of foods is noted. Information about food and fluid intake is obtained. If the client has followed a diet for weight reduction, the details of the diet plan are pertinent. A high-protein intake can result in temporary renal problems. Clients susceptible to calculi (stone) formation who ingest large amounts of calcium-containing products or have an insufficient fluid intake may form new stones.
Changes in appetite, alterations in taste acuity, and an inability to discriminate tastes are important. These symptoms are as
sociated with the accumulation of nitrogenous waste products from renal failure. Changes in thirst or fluid intake may also produce changes in urine output or other evidence of urologic disorders. Endocrine disorders may also produce changes in thirst, fluid intake, and urine output .
SOCIOECONOMIC STATUS
The socioeconomic status of the client may influence health care practices. People with limited income or no health insurance often ignore physical ailments or delay seeking health care because they lack the funds to pay for diagnostic tests or treatment. They may also have difficulty following medical advice, having prescriptions filled, and keeping follow-up appointments.
The information that a client has about the disease and its symptoms may relate to educational level. Educational level may also affect health-seeking practices. Recurring urinary tract infections often result from inadequate or incomplete treatment, including lack of follow-up to ensure eradication. The lack of money to pay for antibiotics or nutritious foods or the lack of knowledge or motivation to select healthful foods may inhibit full recovery.
The client’s health beliefs affect the approach to health and illness. Cultural background or religious affiliation may influence the belief system.
The language used by clients may be different from that used by the health care professional. Anatomic or medical terms may have no meaning for the client (Table 69-4). When obtaining a history, the nurse listens to and explores the terms used by the client. By using the client’s own terms, the nurse may help him or her to provide a more complete and thorough description of the problem. This technique may increase the amount of information communicated and decrease the client’s discomfort when discussing bodily functions.
CURRENT HEALTH PROBLEMS
The effects of renal failure result in changes in all body systems. Therefore all of the client’s current health problems are documented. The client is encouraged to describe all health concerns, because some renal and urologic disorders are associated with symptoms that are related to other body systems or that occur as generalized problems. Recent upper respiratory problems, generalized musculoskeletal discomfort, or gastrointestinal (GI) problems may be related to problems of kidney function.
The kidney and urologic system are assessed specifically. The client is asked about any changes in the appearance (color, odor, clarity) of the urine, pattern of urination, ability to initiate or control voiding, and other unusual symptoms. Urine that is reddish, dark brown or black, greenish, or otherwise different from the usual yellowish, straw color usually prompts the client to seek health care assistance. Urine typically has a mild but distinct odor of ammonia. An increase in the intensity of color, a change in odor quality, or a decrease in urine clarity may suggest infection.
The client is asked about changes in urination patterns, such as nocturia, frequency, or an increase or decrease in the amount of urine. The normal urine output for adults is 1 mL/kg/hr, or approximately 1500 to 2000 mL/day.
COMMONLY USED RENAL AND URINARY TERMS
anuria Total urine output of less than 100 mL In 24 hours
azotemia Increased blood urea nitrogen and serum creati-nine levels suggestive of renal impairment but without outward symptoms of renal failure
dysuria Discomfort or pain associated with micturition
frequency Feeling the need to void often, usually voiding small amounts of urine each time; may void every hour or even more frequently than hourly
hesitancy Difficulty in initiating the flow of urine, even when the bladder has sufficient urine to initiate a void and the sensation of the need to void is present
micturition The act of voiding
nocturia Awakening prematurely from sleep because of the need to empty the bladder
oliguria Decreased urine output; total urine output between 100 and 400 mL in 24 hours
polyuria Increased urine output; total urine output usually greater than 2000 mL in 24 hours
uremia Full-blown signs and symptoms of renal failure; sometimes referred to as the uremic syndrome, especially if the cause of the renal failure is unknown
urgency A sudden onset of the feeling of the need to void immediately; may result in incontinence if the client is unable to locate or get to toileting facilities quickly
FOR NURSING
How does one assess a urinary elimination problem?
The purpose of this article is to describe how a bladder diary was used in research with residents of retirement settings. Bladder diaries are similar to intake and output records but are self-recorded by clients. It reviews different methods of collecting information about fluid consumed and urine eliminated. The narrative details the written record used by 51 subjects in a self-care community of retired individuals and the instructions given to participants so as to yield specific and accurate information.
The author concludes that bladder diaries were used successfully and allow both the client and health care provider to visualize daily voiding patterns. Based on bladder diary data, nurses can diagnose, plan, and intervene to manage voiding problems such as incontinence.
Critique. The clients in this study were physically mobile, able to write, and cognitively intact. Although self-reported bladder diaries may not apply to all clients with elimination problems, the forms and techniques described in this report specify a useful assessment tool that can be used in a variety of community settings.
Implications for Nursing. Bladder diaries can assist the nurse and client in determining the patterns of intake and voiding. Diaries can also be used to evaluate responses to interventions.
Based Practice for Nursing box above). The nurse also asks the following:
• If the client has difficulty initiating urine flow
• If a burning sensation or other discomfort is present on urination
• If the force of the urine stream is decreased (in men)
The nurse asks about any loss of urinary continence. Situations that increase intra-abdominal pressure (e.g., coughing and sneezing) may result in the involuntary passage of urine.
Clients may also report a persistent dribbling of urine.
The onset of pain in the flank, in the lower abdomen or pelvic region, or in the perineal area is often of great concern and usually prompts the client to seek assistance. The nurse inquires about the onset, intensity, and duration of the pain, its location, and its association with any activity or event.
Pain associated with renal or ureteral irritation is often severe and spasmodic. Pain that radiates into the perineal area, groin, scrotum, or labia is described as renal colic. Renal colic pain is usually associated with distention or spasm of the ureter, such as in an obstruction or the passing of a stone. Renal colic pain may be intermittent or continuous and may even be systemic with pallor, diaphoresis, and hypotension. These general symptoms occur because of the location of the nerve tracts associated with the kidneys and ureters.
Because the kidneys are close to the GI organs and the nerve pathways are similar, GI symptoms may be part of the client’s presenting history. These renointestinal reflexes often complicate the detailed description of the renal problem.
Uremia results from the accumulation of nitrogenous waste products in the blood, a result of renal failure. Symptoms include anorexia, nausea and vomiting, muscle cramps, pruritus (itching), fatigue, and lethargy.
Physical Assessment
The physical assessment of the client with a known or suspected renal or urologic disorder includes an assessment of general appearance, a general review of body systems, and specific structure and functions of the renal/urinary systems.
The nurse assesses the general appearance of the client and checks for a yellowish skin color and the presence of any rashes, bruising, or other discoloration. The skin and tissues may show edema, which with renal disorders may be detected in the pedal (foot), pretibial (shin), sacral tissues, and around the eyes. The lungs are auscultated to determine whether fluid is present. Weight and blood pressure measurements are obtained for comparison purposes.
The nurse assesses the client’s general level of consciousness and level of alertness, noting deficits in concentration, thought processes, or memory. Family members may report subtle changes. Such cognitive changes may be the result of an insufficient clearance of waste products when renal disease is present.
ASSESSMENT OF THE KIDNEYS, URETERS, AND BLADDER
Assessment of the kidneys, ureters, and bladder is performed in conjunction with an abdominal assessment. Auscultation is performed before percussion and palpation because these activities can enhance bowel sounds and obscure abdominal vascular sounds.
Inspection
The nurse inspects the abdomen and the flank regions with the client in both the supine and the sitting position. The client is observed for asymmetry (e.g., swelling) or discoloration (e.g., bruising or redness) in the flank region, especially in the area of the costovertebral angle (CVA). The CVA is located between the lower portion of the twelfth rib and the vertebral column.
Auscultation
The nurse listens for a bruit over each renal artery on the mid-clavicular line. A bruit is an audible swishing sound produced when the volume of blood or the diameter of the blood vessel changes. A bruit is usually associated with blood flow through a narrowed vessel, as in renal artery stenosis.
■ Palpation
Renal palpation identifies masses and areas of tenderness in or around the kidney. The abdomen is lightly palpated in all quadrants. The nurse asks about areas of tenderness or discomfort and examines nontender areas first. The outline of the bladder may be seen as high as the umbilicus in clients with severe bladder distention. Special training and practice under the guidance of a qualified practitioner are necessary; therefore appropriate education is essential before attempting the procedure. If tumor or aneurysm is suspected, palpation may harm the client.
Because the kidneys are deep, posterior structures, palpation is easier in thin clients who have little abdominal musculature. For palpation of the right kidney, the client assumes a supine position while the nurse places one hand under the right flank and the other hand over the abdomen below the lower right part of the rib cage. The lower hand raises the flank, and the upper hand depresses the anterior abdomen as the client takes a deep breath (Figure 69-10). The left kidney is deeper and rarely palpable. A transplanted kidney is readily palpable in either the lower right or left abdominal quadrant. The kidney should feel smooth, firm, and nontender.
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Fig. Renal Percussion
A distended bladder sounds dull when percussed. After gently palpating to determine the general outline of the distended bladder, the nurse begins percussion on the skin of the lower abdomen and continues in the direction of the umbilicus until dull sounds are no longer produced.
If the client identifies flank pain or tenderness, the nontender flank is percussed first. The client assumes a sitting, side-lying, or supine position, and the nurse forms one hand into a clenched fist. The heel of the other hand and the little finger form a flat area with which a firm thump to the CVA area can be quickly administered. Costovertebral tenderness is highly suggestive of kidney infection or inflammation. Clients with inflammation or infection in the kidney or adjacent structures may describe their pain as severe or as a constant, dull ache.
I ASSESSMENT OF THE URETHRA
Using a good light source and wearing gloves, the nurse inspects the urethra by examining the meatus and surrounding tissues. Any unusual discharge such as blood, mucus, and purulent drainage is noted. The skin and mucous membranes of surrounding tissues are inspected, and the presence of lesions, rashes, or other abnormalities of the penis or scrotum or of the labia or vaginal orifice is documented. Urethral irritation is suspected when the client reports discomfort with urination.
Psychosocial Assessment
Concerns about the urologic system may evoke fear, anger, embarrassment, anxiety, guilt, or sadness in the client. Childhood learning often includes privacy with regard to urination habits. Urologic disorders may stimulate previously forgotten memories of difficult toilet training and bedwetting or of childhood experiences of exploring one’s body. The client may ignore symptoms or delay seeking health care because of emotional responses or cultural taboos about the urogenital area.
, CRITICAL THINKING CHALLENGE
The client is a 62-year-old woman who has had a backache in the lower left flank area for a month. She has been seen by an orthopedic specialist, who has determined the pain is not from a strained muscle or spinal problem. This women is about
• What personal or demographic data should you obtain?
• What additional questions should you ask this client regard ing her pain?
• How would you proceed in gathering physical assessment data?
Diagnostic Assessment
LABORATORY TESTS
I Blood Tests
SERUM CREATININE
Serum creatinine is a measurement of the end product of muscle and protein metabolism. Creatinine is filtered by the kidneys and excreted in the urine. Because muscle mass and metabolism are usually constant, the serum creatinine level is an excellent indicator of kidney function. Normal serum creatinine levels vary with age, gender, and body muscle mass. The normal serum creatinine value is slightly higher in adult men than in adult women (Chart 69-3). In general, men have a larger muscle mass than do women, but there are exceptions. Muscle mass and the amount of creatinine produced diminish with age. Because of decreased rates of creatinine clearance, however, the serum creatinine level remains relatively constant in older adults unless renal disease is present.
No common pathologic condition other than renal disease results in an increase in serum creatinine level. The serum creatinine level does not increase until at least 50% of the renal function is lost, and therefore any elevation of serum creatinine values is important.
BLOOD UREA NITROGEN
Blood urea nitrogen (BUN) measures the renal excretion of urea nitrogen, a by-product of protein metabolism in the liver. Urea nitrogen is produced primarily from food sources of protein, which undergo metabolism by the liver. The kidneys filter urea nitrogen from the blood and excrete the nitrogenous waste in urine. BUN levels indicate the extent of renal clearance of this nitrogenous waste product.
Other factors may influence the BUN level, and therefore an elevation does not always represent renal disease (see Chart 69-3). For example, rapid cell destruction from infection or steroid therapy may elevate BUN level. In addition, blood is a protein. If blood is present in body tissues, the re-absorption of the blood protein is processed by the liver, resulting in an increased BUN level.
The liver must function properly to produce urea nitrogen. When liver and kidney dysfunction are both present, urea nitrogen levels are actually decreased; this decrease reflects the liver failure but not the kidney failure. The BUN level is not always elevated with kidney disease and is not the most reliable indicator of kidney function. However, an elevated BUN level is highly suggestive of kidney dysfunction.
RATIO OF BLOOD UREA NITROGEN TO SERUM CREATININE
The BUN/creatinine ratio determines whether factors such as dehydration or lack of renal perfusion are causing the elevated BUN level. When a blood volume deficit (dehydration) or hy-poperfusion exists, the BUN level rises more rapidly than the serum creatinine level. As a result, the ratio of BUN to creati-nine is increased.
When both the BUN and serum creatinine levels increase at the same rate, the BUN/creatinine ratio remains normal. However, the elevated serum creatinine and BUN levels suggest renal dysfunction that is not related to acute volume depletion or hypoperfusion.
■ Urine Tests
■ URINALYSIS
Urinalysis is a usual part of any complete physical examination but is particularly useful for clients with suspected kidney or urologic disorders (Chart 69-4). Ideally, the urine specimen is collected at the first morning’s voiding; specimens obtained at other times may not be adequately concentrated. The specimen may be collected by several techniques.
COLOR, ODOR, AND TURBIDITY. The color of urine is derived from urochrome pigment. Variations in color may result from increased levels of urochrome or other pigments, changes in the concentration or dilution of the urine, and the presence of drug metabolites in the urine. Urine smells faintly like ammonia and is normally clear without turbidity (cloudiness) or haziness.
SPECIFIC GRAVITY. The specific gravity of urine measures the concentration or density of urine compared to water. The specific gravity of urine ranges from 1.000 (the specific gravity of water) to greater than 1.035. In kidney disease, increases and decreases in specific gravity may not reflect systemic fluid volume. For example, dilute urine with a decreased specific gravity may occur in a dehydrated client who has a lack of nephron receptors for antidiuretic hormone.
An increase in specific gravity occurs with dehydration, decreased kidney perfusion, or the presence of antidiuretic hormone (ADH). (ADH production is normally increased with stress, surgery, anesthetic agents, and certain drugs such as morphine and oral antidiabetic agents.) In each of these situations the expected kidney response is to reabsorb water and decrease urine output. As a result, the urine produced is more concentrated.
A decrease in specific gravity occurs with increased fluid intake, diuretic administration, and diabetes insipidus. In each of these situations, the normal kidney response is to excrete more water; thus urine output is increased. In kidney disease, the specific gravity decreases because there is less solute, and it does not vary with changes in plasma osmolality (e.g., it becomes fixed).
pH. A pH value less than 7 is considered acidic, and a value greater than 7 is considered alkaline. Various factors influence the acidity or alkalinity of urine. A diet high in certain fruits and vegetables results in a more alkaline urine, whereas a high-protein diet produces a more acidic urine. The presence of Escherichia coli in the urine also results in an acidic urine.
Urine specimens become more alkaline when left standing unrefrigerated for more than 1 hour, if urea-splitting bacteria are present, or if a specimen is left uncovered. Alkaline urine increases cell breakdown; thus the presence of red blood cells may be missed on analysis. The nurse ensures that urine specimens are covered and delivered to the laboratory promptly or refrigerated. During metabolic or respiratory acidosis or alka-losis, the kidneys, along with blood buffers and the lungs, should respond appropriately to maintain a normal serum pH. Chapters 15 and 16 discuss acid-base balance and imbalance.
GLUCOSE. Glucose is filtered at the glomerulus and is reabsorbed in the proximal tubule of the nephron. When the blood glucose level rises above 220 mg/dL, the renal threshold for reabsorption is usually exceeded, and glucose is excreted in the urine. Variations in the renal threshold for glucose occur in many clients, such as those who experience any infection or those who have had diabetes mellitus for a number of years. It is possible that their serum glucose level may be high (e.g., greater than 400 mg/dL), and glucose may still not be present in the urine.
KETONE BODIES. Three types of ketone bodies are acetone, acetoacetic acid, and beta-hydroxybutyric acid. Ketone bodies are by-products of the incomplete metabolism of fatty acids. Normally there are no ketones in urine. Ketone bodies are produced when fat sources are used instead of glucose to provide cellular energy. When ketones are present in the blood, they are partially excreted in the urine.
PROTEIN. Protein, such as albumin, is not normally present in the urine. Levels greater than 300 mg/24 hr, or 200 xg/min, are abnormal. The glomerular membrane is semiper-meable to small molecules; protein molecules are too large to pass through this semipermeable membrane. When permeability of the glomerular membrane is increased, protein molecules pass through and are excreted in the urine. Increased glomerular membrane permeability may be caused by infection, inflammation, or immunologic problems. Certain systemic processes result in the production of abnormal proteins, such as globulin. These proteins are not detected with routine
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LABORATORY PROFILE |
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Urinalysis |
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Test |
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Significance of Abnormal Findings |
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Color |
Pale yellow |
Dark amber indicates concentrated urine. |
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Very pale yellow indicates dilute urine. |
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Dark red or brown indicates blood in the urine; brown also |
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may indicate increased urinary bilirubin level; red may also |
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indicate the presence of myoglobin. |
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Other color changes may result from diet or medications. |
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Odor |
Specific aromatic odor, similar to ammonia |
Foul smell indicates possible infection, dehydration, or inges- |
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tion of certain foods or drugs. |
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Turbidity |
Clear |
Cloudy urine indicates infection or sediment or high levels of urinarv orotein |
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Specific gravity |
Usually 1,010-1.025; possible range |
Increased in decreased renal perfusion, inappropriate antidi- |
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1.000-1.030; after 12-hr fluid restriction |
uretic hormone secretion, or congestive heart failure. |
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> 1.025 |
Decreased in chronic renal insufficiency, diabetes insipidus, |
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Older adult; Decreased because of de- |
malignant hypertension, diuretic administration, and lithium |
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creased concentrating ability |
toxicity. |
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PH |
Average: 6; possible range: 4.6-8 |
Changes are caused by diet, the administration of medica- |
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tions, infection, freshness of the specimen, acid-base im- |
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balance, and altered renal function. |
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Glucose |
<0.5 g/day (<2.78 mmol/L) |
Presence reflects hyperglycemia or a decrease in the renal |
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threshold for glucose. |
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Ketones |
None |
Presence reflects incomplete metabolism of fatty acids, as in |
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diabetic ketoacidosis, prolonged fasting, anorexia nervosa. |
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Protein |
8-18 mg/dL (10-140 mg/L) |
Increased amounts may indicate stress, infection, recent |
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strenuous exercise, or glomerular disorders. |
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Bilirubin |
None |
Presence suggests hepatic or biliary disease or obstruction. |
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(urobilinogen) |
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Red blood cells |
0-2 per high-power field |
Increased amounts are normal with indwelling or intermittent |
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(RBCs) |
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catheterization or menses but may reflect tumor, stones, |
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trauma, glomerular disorders, cystitis, or bleeding disorders. |
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White blood |
Males: 0-3 per high-power field |
Increased amounts may indicate an infectious or inflammatory |
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cells (WBCs) |
Females: 0-5 per high-power field |
process anywhere in the renal/urinary tract, renal transplant |
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rejection, fever, or exercise. |
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Casts |
A few or none, composed of RBC or |
Increased amounts indicate the presence of bacteria or pro- |
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WBC, protein, or tubular cell casts |
tein, which is seen in severe renal disease and could also |
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indicate urinary calculi. |
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None |
Presence of normal or abnormal crystals may indicate that the |
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specimen has been allowed to stand. |
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Bacteria |
<1000 colonies/mL |
Increased amounts indicate the need for urine culture to de- |
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termine the presence of urinary tract infection. |
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Parasites |
None |
Presence of Trichomonas vaginalis indicates infection, usually |
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of the urethra, prostate, or vagina. |
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Nitrates |
None |
Presence suggests bacteria, usually Escherichia coll. |
A random finding of proteinuria followed by a series of negative (normal) findings does not imply renal disease. If infection is suspected to be the cause of the proteinuria, urinal-yses after elimination of the infection should be negative for protein. Persistent proteinuria needs further investigation.
Microalbuminuria is the presence of albumin in the urine that is not measurable by a urine dipstick or conventional urinalysis procedures. Specialized immunoassay tests can quickly analyze a freshly voided urine specimen for microscopic levels of albumin. The normal microalbumin levels in a freshly voided random specimen should range between 2.0 to 20 mg/mmol for men and 2.8 to 28 mg/mmol for women. Higher levels indicate microalbuminuria and could mean the presence of very early kidney disease, especially in clients with diabetes mellitus. For 24-hour urine specimens, levels of 30 to 300 mg/24 hr, or 20 to 200 xg/min, indicate microalbuminuria.
SEDIMENT. Urine sediment refers to particles in the urine. These particles include cells, casts, crystals, and bacteria.
CELLS. Types of cells abnormally present in the urine may include tubular cells (from the tubule of the nephron), epithelial cells (from the lining of the urinary tract), red blood cells (RBCs), and white blood cells (WBCs).
CASTS. Casts are structures formed around other particles. There may be casts of cells, bacteria, or protein. When casts are formed, there is a clumping or agglutination of the element, and gelatinous substances form the surrounding
Rationale
VOIDED URINE
Collect the first specimen voided in the morning.
Send the specimen to the laboratory as soon as possible.
Refrigerate the specimen if a delay is unavoidable.
CLEAN-CATCH SPECIMEN
Explain the purpose of the procedure to the client.
Instruct the client to self-clean before voiding.
Instruct the female client to separate the labia and use the sponges and solution provided to wipe with three strokes over the urethra. The first two wiping strokes are over each side of the urethra; the third wiping stroke is centered over the urethra (from front to back).
Instruct the male client to retract the foreskin of the penis and to similarly clean the urethra, using three wiping strokes with the sponge and solution provided (from the head of the penis downward).
Instruct the client to initiate voiding after cleaning. The client then stops and resumes voiding into the container. Only
CATHETERIZED SPECIMEN
For nonindwelling (straight) catheters:
Avoid routine use.
Follow the facility’s procedures for catheterization technique. For indwelling catheters:
Apply a clamp to the drainage tubing, distal to the injection port.
Clean the injection port cap of the catheter drainage tubing with an appropriate antiseptic. Povidone-iodine solution or alcohol is acceptable.
Insert a sterile 5-mL syringe into the port and aspirate the quantity of urine required.
Inject the urine sample into a sterile specimen container.
Remove the clamp to resume drainage.
Properly dispose of the syringe.
24-HOUR URINE COLLECTION
Instruct the client thoroughly.
Provide written materials to assist in instruction.
Place signs appropriately.
Inform all personnel or family caregivers of test in progress.
Check laboratory or procedure manual on proper technique for maintaining the collection (e.g., on ice, in a refrigerator, or with a preservative). On initiation of the collection, ask the client to void, discard the urine, and note the time. If a Foley catheter is in use, empty the tubing and drainage bag at the start time and discard the urine.
Collect all urine for the next 24 hr. 24 hr after initiation, ask the client to empty the bladder and add that urine to the container. Do not remove urine from the collection container for other specimens.
Urine is more concentrated in the early morning.
After urine is collected, cellular breakdown results in more alkaline urine.
Refrigeration delays the alkalinization of urine. Bacteria are more likely to multiply in an alkaline environment.
Correct technique is needed to obtain a valid specimen.
Surface cleaning is necessary to remove secretions or bacteria from the urethral meatus. A midstream collection further removes secretions and bacteria because urine flushes the distal portion of the internal urethra.
An improperly collected specimen may result in inappropriate or incomplete treatment.
The client’s understanding and the nurse’s assistance ensure proper collection. The one-time passage of a urinary catheter may be necessary to obtain an uncontaminated specimen for analysis or to measure the volume of residual urine.
These procedures minimize bacterial entry.
Collection of urine from an indwelling catheter or tubing is performed when clients have catheters for continence or long-term urinary drainage. Clamping allows urine to collect in the tubing at the location where the specimen is obtained. Surface contamination is prevented by following the cleaning
procedures.
A minimum of 5 mL is needed for culture and sensitivity (C&S) testing. A sterile container is used for C&S specimens. A 24-hr collection of urine is necessary to quantify or calculate the rate of clearance of a particular substance. Instructional materials for clients, signs, and so on remind clients and staff to ensure that the total collection is completed.
Proper technique prevents breakdown of elements to be measured.
Proper techniques ensure that all urine formed within the 24-hr period is collected. Urine in the container is not considered a “fresh” specimen and may be mixed with preservative.
Decreased amounts indicate a deterioration in renal function caused by renal disease, shock, hypovolemia, or any condition affecting muscle. Increased amounts occur with infections, exercise, diabetes mellitus, and meat meals. disease is present. Increased amounts commonly result from a high-protein
diet, dehydration, trauma, or sepsis. Decreased amounts are seen in hemorrhage, shock, hy-peraldosteronism, and prerenal acute renal failure.
Increased amounts are common with diuretic therapy, excessive salt intake, hypokalemia, and acute tubular necrosis.
Decreased amounts are seen in certain renal diseases, malabsorption syndrome, pyloric obstruction, prolonged nasogastric tube drainage, diarrhea, diaphoresis, congestive heart failure, and emphysema. Increased amounts are seen with hypokalemia, adrenal insufficiency, and massive diuresis.
Decreased amounts are often associated with hypocal-cemia, hypoparathyrodism, nephrosis, and nephritis.
Increased amounts are commonly seen with calcium renal stones, hyperparathyroidism, sarcoidosis, certain cancers, immobilization, and hypercalcemia.
Increased amounts occur with pheochromocytoma, neu-roblastomas, stress, or strenuous exercise.
Increased amounts indicate glomerular disease, nephrotic syndrome, diabetic nephropathy, urinary tract malignancies, and irritations.
“Epinephrine and norepinephrine only; dopamine is not measured.
BACTERIA. Bacteria in a urine sample multiply quickly, so the specimen must be analyzed promptly. Normally urine is sterile, but it can be contaminated easily by perineal bacteria or airborne pathogens during collection.
URINE FOR CULTURE AND SENSITIVITY
The nurse may collect a sample of urine for laboratory determination of the number and types of pathogens present. The presence of clinical symptoms and unexplained bacteria in a urinal-ysis specimen are indications for urine culture and sensitivity testing. When bacterial colonies are present, they are placed in a medium containing different antibiotic drugs to determine which drugs are effective in killing or stopping the growth of the bacteria (sensitivity). Those drags to which the microorganisms are sensitive or resistant are reported to guide decisions about needed therapy. A clean-catch or catheter-derived specimen is always preferred for culture and sensitivity testing.
COMPOSITE URINE COLLECTIONS
When ordered, urine collections are made for a number of hours (e.g., 24 hours) for laboratory quantitative and qualitative analysis of one or more substances. Collections are often ordered to measure levels of urinary creatinine or urea nitrogen, sodium, chloride, calcium, catecholamines, or other components (Chart 69-5). For a composite urine specimen, all urine within the designated time frame must be collected (see Table 69-5). If other voided or catheterized specimens must be obtained while the collection is in progress, the nurse measures and appropriately documents the amount collected but not added to the timed collection.
The urine collection may need to be refrigerated or stored on ice to prevent changes in the urine during the collection
time. The nurse follows the procedure from the laboratory for urine storage. The urine collection must be free from fecal contamination. Menstrual blood and toilet tissue also contaminate the specimen and can invalidate the results.
The collection of urine for a 24-hour period is often more difficult than it seems. With hospitalized clients, the cooperation of staff personnel, the client, family members, and visitors is essential. Placing signs in the bathroom, instructing the client and family, and emphasizing the need to save the urine are helpful.
К CREATININE CLEARANCE TEST
Creatinine clearance is a calculation of glomerular filtration rate. It is the best indication of overall kidney function. The amount of creatinine cleared from the blood (e.g., filtered into the urine) is measured in the total volume of urine excreted in a defined period. A urine specimen for a creatinine clearance test is usually collected for 24 hours, but it can be collected for shorter periods (e.g., 8 or 12 hours). The calculation requires a comparison with the blood creatinine level, and therefore a blood specimen for creatinine must also be collected.
The laboratory or the physician calculates the creatinine clearance. Because the client’s age, gender, height, weight, diet, and activity level influence the expected amount of creatinine to be excreted, these variables are considered in the interpretation of creatinine clearance test results.
The following formula is used to calculate creatinine clearance:
Creatinine clearance = U x V/P x T
where U is creatinine in urine (mg/dL), V is volume of urine (mL/24 hr), P is creatinine in plasma or blood (mg/dL), and T is time (minutes).
The rate of creatinine clearance is expressed as milliliters per minute per
Creatinine clearance measurements are necessary to determine the client’s current kidney function. Decreases in the creatinine clearance rate may require modification of drug dosing and often signifies the need for further investigation of the cause of kidney deterioration.
URINE ELECTROLYTES
Urine samples may be collected for the analysis of urine electrolyte levels (e.g., sodium and chloride). Normally the amount of sodium excreted in the urine is nearly equal to that consumed. Urine sodium levels of less than 10 mEq/L indicate that the tubules are functioning to conserve (reabsorb) sodium.
OSMOLALITY
Osmolality is a measure of the concentration of particles in solution, in this case the concentration of solutes in urine. These solutes include electrolytes and solutes such as glucose, urea, and creatinine.
BLOOD/PLASMA OSMOLALITY. The kidneys excrete or reabsorb water to maintain a blood osmolality in the range of 285 to 295 mOsm/kg. Osmolality is slightly higher in older adult clients (285 to 301 mOsm/kg). When blood osmolality is decreased, the release of antidiuretic hormone (ADH) is inhibited. Without ADH, the distal tubule and collecting ducts are not permeable to water. As a result, water is excreted, not reabsorbed, and blood osmolality increases. When blood osmolality increases, ADH is produced. With ADH production, the distal tubule is made permeable to water. Consequently, water is reabsorbed, and blood osmolality decreases.
URINE OSMOLALITY.
Urine osmolality can vary from 50 to 1400 mOsm/kg water, depending on the clinical and hy-dration status of the client and the functional status of the kidneys. With average fluid intake, the range for urine osmolality is 300 to 900 mOsm/kg water. The fixed acids and other wastes that are continually produced constitute a solute load that must be excreted in the urine on a regular basis. This is referred to as obligatory solute excretion. If the client has lost excessive fluids, the renal response is to conserve water, preserve blood osmolality, and excrete small amounts of highly concentrated urine. Many factors such as diet, medications, and activity can influence urine osmolality. Thus increased urine osmolality reflects a concentrated urine with less water than solutes. A decreased urine osmolality reflects a dilute urine with more water than solutes.
■ RADIOGRAPHIC EXAMINATIONS
Radiographic and other special procedures are used to diagnose abnormalities within the genitourinary system (Table 69-6). The nurse explains the procedures thoroughly to the client, prepares the client, and provides postprocedural care.
I Kidney, Ureter, and Bladder X-Ray Examination
Radiographic examination of the kidneys, ureters, and bladder (KUB) is a plain film of the abdomen taken without any specific client preparation. The KUB study shows gross anatomic features and may show obvious stones, strictures, calcifications, or obstructions in the urinary tract. This test identifies the organs’ shape, size, and relationship to other parts of the urinary tract. Other tests are necessary for diagnosis of functional or structural abnormalities.
There is no discomfort or risk from this procedure. The nurse tells the client that the films will be taken while the client is in a supine position. No specific postprocedure care is necessary.
Intravenous Urography
Other names for intravenous urography include excretory urography and (the older term) intravenous pyelography (IVP).
CLIENT PREPARATION. Before urography, the nurse assesses the client (Chart 69-6), institutes bowel preparation, and teaches the client. Allergy information is reported to the physician. Contrast reactions can be minor (nausea and vomiting, urticaria, itching, sneezing), moderate (nephrotoxic effects, congestive heart failure, pulmonary edema), or severe
(bronchospasm, anaphylaxis). If the diagnostic test is to be performed in the presence of minor allergy, the physician orders preprocedural medications such as a steroid (methyl–prednisolone or prednisone), and an antihistamine (diphenhy–dramine hydrochloride [Benadryl, Allerdryl‘*’]) to suppress the allergic response (Cohan & Ellis, 1997). The nurse explains the rationale for the procedure to the client.
Procedures to ensure that films provide adequate visualization vary according to the radiologist’s preferences. Some radiologists recommend a light evening meal or clear liquids, then fasting (NPO status) from midnight on the night before the procedure. Others recommend increased fluid intake to prevent dehydration up until the time of the procedure. Because of the possibility of a vomiting reaction to the intravenous (IV) contrast, however, the physician may prefer the client to remain on NPO status at least a few hours before the procedure. The physician orders hydration with IV fluids as indicated.
The physician orders a bowel preparation to remove fecal contents, fluid, and air from the gut, which permits an adequate outline of the lower poles of the kidneys, ureters, and bladder. Bowel preparation procedures vary but usually include the use
BEST PRACTICE
Assessing the Client About to Undergo a Diagnostic Test or Interventional Procedure Using Contrast Media
Before the procedure:
• Ask the client if he or she has ever had a reaction to contrast media. (Such a client has the highest risk for having another reaction.)
• Ask the client about a history of asthma. (Clients with asthma have been shown to be at greater risk for contrast reactions than the general public; when
reactions do occur, they are more likely to be severe.)
• Ask the client about known hay fever or food or medication allergies, especially to seafood, eggs, milk, or chocolate. (Contrast reactions have been reported to be as high as 15% in these clients.)
• Ask the client to describe any specific allergic reactions (e.g., hives, facial edema, difficulty breathing, bronchospasm).
• Assess for a history of renal insufficiency and for conditions that have been implicated in increasing the chance of developing renal failure after contrast media (e.g., diabetic nephropathy, class IV heart failure, dehydration, concomitant use of potentially nepnrotoxic medications such as the aminoglycosides or NSAIDs, and cirrhosis).
• Ask the client if he or she is taking metformin (Glucophage). (Metformin must be discontinued at least 48 hours before any study using contrast media because the life-threatening complication of lactic acidosis, although rare, could occur.)
• Assess hydration status by checking blood pressure,
heart and respiratory rates, mucous membranes, skin turgor, and urine concentration.
• Ask the client when he or she last ate or drank anything.
Enemas also may be prescribed but are controversial because air and fluid can be introduced with inadequate expulsion of fecal contents.
CLIENT EDUCATION GUIDE Excretory Urogram
• The urogram outlines your urinary tract and helps deter mine any problems there.
• Notify your nurse or physician if you have had any reac tions (allergic or otherwise) to any food or drugs, especially shellfish (shrimp, scallops, crab, lobster, and so on) or iodine, or to x-ray “dyes” such as contrast media; if you have a history of asthma; or if you are taking metformin (Glucophage) or Glucovance.
• The day before the test, follow the instructions about changes in your diet and fluid intake to be sure that as much information as possible is gained from the test.
• After you start the bowel preparation, you may need to be close to toileting facilities. The preparation medica tions usually work quickly.
• You will be lying on an x-ray table with the x-ray machine above you for most of the procedure.
• A pressure band, similar to a large blood pressure cuff, may be placed around your stomach or abdomen to help obtain better x-ray pictures.
• If you do not already have an IV access site, one will be started to give you the contrast agent.
• After the contrast is injected, you may feel a sense of warmth or heat as it travels throughout your body. You also may have a taste in your mouth that is sometimes described as metallic. These sensations last only a few seconds or minutes.
• When the pressure band is inflated, you may feel some tightness around your abdomen. The sensation is similar to the feeling on your arm when you have your blood pressure taken.
• A series of x-ray pictures will be taken. You may be asked to empty your bladder and return to the table for more films. You also may be asked to have a standing film taken.
• After the test is completed, you are usually able to resume your normal activities and diet.
• The contrast will be excreted normally in your urine. You will not notice any change in the color or characteristics of your urine.
• Please do not hesitate to ask your nurse, physician, or x-ray technologist any question, no matter how slight the question may seem to you. It is important that you have as much understanding as possible.
CONSIDERATIONS FOR OLDER ADULTS
BUS Bowel preparation procedures increase the risk for dehydration, especially in older clients. To help prevent dehydration, the nurse contacts the testing department and requests that urograms be scheduled early in the day for older clients.
The contrast medium (dye) is potentially nephrotoxic. The risk for contrast-induced renal failure is greatest in clients who are older or dehydrated, who have some renal insufficiency (e.g., serum creatinine levels greater than 1.5 mg/dL), or who are also taking other nephrotoxic drugs. These clients usually require additional IV fluids before the procedure to maintain hydration and to decrease the nephrotoxic risk. Diuretics may be administered immediately after the dye is injected to enhance its excretion.
The nurse instructs the client in the preparation procedures for the urogram and explains the procedure so he or she knows what to expect in the examination room (Chart 69-7). The nurse intervenes on behalf of the client to ensure that questions are answered before the procedure.
PROCEDURE. A radiopaque contrast medium (dye) is injected intravenously with the client in a supine position. As blood (with the dye) rapidly circulates into the kidney blood vessels and is filtered by the glomeruli, the dye is excreted in the urine. A series of x-ray films are taken at various times after injection. When ordered, nephrotomograms are taken at the same time as the urogram. Tomograms provide images of different planes of tissue and show any abnormalities present at varying depths. The technologist then asks the client to empty the bladder and return for a few more films. An outline of the kidneys, ureters, and bladder results as urine containing the dye is excreted.
The urogram provides information about the following:
• The number, size, shape, and location of the kidneys
• The adequacy of uptake (filling) and the rate of excretion of contrast medium
• The number, size, location, appearance, and patency of the calices, pelves, and ureters
– The size, location, and nature of the urinary bladder
FOLLOW-UP CARE. After the urogram, the nurse monitors the client for altered renal function and other effects from the dye. Adequate hydration is ensured by encouraging the client to take fluid orally or by administering IV fluids. Hydration decreases the risk for renal deterioration. Blood creati-nine levels are monitored to determine ongoing renal function.
• Computed Tomography
CLIENT PREPARATION. The nurse informs the client that a computed tomography (CT) scan is performed to provide three-dimensional information about the kidneys, ureters, bladder, and surrounding tissues.
scan is usually performed after other diagnostic procedures and can provide information about tumors, cysts, abscesses, other masses, obstruction, and certain blood vessel abnormalities.
A bowel preparation with laxatives or an enema and a light meal the evening before the procedure is needed. The client is giveothing by mouth (NPO status) after midnight on the night before the examination. For clients having the CT scan with dye, the physician orders preprocedural IV hydration. The nurse assesses for any allergy to dye and intervenes as with IV urography.
PROCEDURE. The CT scan is performed in a special room, usually in the radiology department. An IV injection of radiopaque dye may be administered before starting the imaging procedures. The use of dye may be eliminated in clients at risk for contrast media-induced acute renal failure, but the images produced are less distinct. Tomograms are obtained at various levels.
FOLLOW-UP CARE. No special follow-up care is necessary unless a dye was used. In that case, the follow-up care is the same as for IV urography.
■ Cystography and Cystourethrography
CLIENT PREPARATION. The nurse explains the procedure to the client undergoing a cystography or cystourethrography. A urinary catheter is temporarily needed to instill a contrast medium (dye). The dye is necessary for visualization of the lower urinary tract.
PROCEDURE. In both cystography and cystourethrography, dye is instilled into the bladder via a urethral catheter. After bladder filling, a variety of films are obtained from the front, back, and side positions. For the voiding cystourethro-gram (VCUG), the client is requested to void, and films are taken during the voiding. A VCUG is obtained to determine whether a vesicoureteral reflux is present. The cystogram is often indicated in cases of trauma when urethral or bladder injury is suspected.
FOLLOW-UP CARE. The nurse monitors for the development of infection as a result of catheterization. In this test, the dye is not nephrotoxic because it is not injected into the bloodstream. Fluid intake is encouraged to dilute the urine and reduce the burning sensation from catheter irritation after removal. Because pelvic or urethral trauma may be present, the nurse also monitors for changes in urine output.
i OTHER RENAL DIAGNOSTIC TESTS I Renal Arteriography (Angiography)
CLIENT PREPARATION. The nurse informs the client that an arteriography is used to assess the arterial blood supply of the kidneys. A bowel preparation is given to remove fecal contents, gas, and fluid. A light evening meal is given, and the client is on NPO status until after the procedure. An IV may be placed before the procedure. IV fluids are often given to ensure adequate hydration because a contrast medium (dye) is used as part of the procedure.
The nurse reviews the procedure with the client, answers questions, and reviews the medication regimen and blood study results as indicated. For example, the nurse reviews the profhrombin time if the client has been taking warfarin sodium (Coumadin, Warfilone^). The client also signs an informed consent statement. Renal arteriography is performed to explore suspected causes of decreased renal function such as renovascular hypertension, other vessel abnormalities, and bleeding from trauma.
PROCEDURE. The injection of a radiopaque dye into the renal arteries requires entry into an artery, usually the femoral artery in the groin. After the client is sedated and the skin is prepared and draped, the radiologist injects a local anesthetic. An arterial puncture is then performed through which the angiographic catheter is inserted.
Using fluoroscopy, the radiologist guides the catheter into the abdominal aorta and the renal artery. When the tip of the catheter is positioned at each renal artery, the radiologist injects dye and films are taken. The speed of distribution of the dye and any areas of blood vessel narrowing are noted. Arterial blockage is noted when the dye fails to circulate within the kidney. Extravasation (infiltration) of dye into surrounding tissue indicates vessel rupture, which could be present after trauma.
Visualization of the renal vessels can be improved by using a digital subtraction technique. In the digital subtraction arteriogram (DSA), a computer is used to “subtract out” loops of bowel, ribs, and other structures normally seen on the x-ray film. As a result, even the small-vessel images are improved. In addition, the use of a smaller amount of dye means less risk for nephrotoxicity. DSA procedures may not provide sufficient detail for surgical intervention when used without full arteriography.
FOLLOW-UP CARE. Bleeding from the catheter insertion site and dye-induced reactions are the two most common complications of renal arteriography. The nurse monitors the catheter insertion site for signs of bleeding or swelling. A pressure dressing may have been placed as a preventive measure before the client returned to the nursing area. The nurse ensures that a 5-pound sandbag and ice are available in case of emergency.
The vital signs are monitored as per the physician’s order or according to the agency’s policy, usually every 15 minutes for 1 hour, then every 30 minutes for 2 hours, then every hour for 4 hours, and then every 4 hours. The nurse checks the temperature and color of the extremities and distal pulses. A sudden absence of pulses in the catheterized vessel may reflect hematoma formation or embolization. Hemoglobin and hematocrit levels are monitored closely for 24 hours after the procedure, usually every 6 hours.
The period of absolute bedrest (to prevent bleeding) after arteriography varies. In general, bedrest is maintained for 4 to 6 hours. The nurse instructs the client about the importance of keeping the leg in a straight position for those 4 to 6 hours. A restraint may be used on the leg with the client’s consent. Ankle flexing and weight shifting are encouraged to prevent deep vein thrombosis. If there is no evidence of bleeding after 4 to 6 hours, the client may be permitted to stand to void or may use a bedside commode.
Serum creatinine tests are ordered for several days after the arteriogram to determine whether the procedure has affected kidney function. For some clients with renal insufficiency, the administration of dye may cause an episode of acute renal failure sufficient to require short-term dialysis. Because the test is used to provide information for interventions to restore blood flow and thus preserve kidney function, many clients are willing to accept the risk of short-term dialysis to prevent the need for permanent dialysis. The client is urged to drink fluids after the procedure to ensure adequate excretion of the dye.
■ Renal Biopsy
CLIENT PREPARATION. The nurse explains that a biopsy of the kidney is performed to determine a pathologic reason for unexplained renal dysfunction and to direct or change a course of therapy. The client signs an informed consent or operative permit.
In a closed biopsy, the physician obtains kidney tissue samples percutaneously (through the skin and other tissues). In an open biopsy, the tissues are obtained surgically. Factors to consider include the number of kidneys, the ability of the client to cooperate, and the need for abdominal surgical exploration. If a percutaneous biopsy is selected, the client must have two kidneys, be able to breathe comfortably in a prone position for 30 to 45 minutes, and be able to hold his or her breath on request for several seconds. The client is on NPO status for 4 to 6 hours before the procedure in case a major complication requires immediate surgery.
An open renal biopsy is performed when cancer is suspected or when the client has only one kidney, cannot hold his or her breath, or is unable to tolerate a prone position. If abdominal surgery is necessary for other reasons and a renal biopsy is also needed, the nephrologist may request the surgeon to perform the biopsy, thereby eliminating the need for a second procedure. If an open biopsy is performed, client preparation is the same as for general surgery and anesthesia (see Chapter 17).
Because of the risk for postprocedure bleeding, coagulation studies such as platelet count, activated partial thrombo-plastin time (aPTT), prothrombin time (PT), and bleeding time are performed before surgery. A blood transfusion may be needed to correct a low hemoglobin level before biopsy. Hypertension and uremia increase the risk for bleeding and the physician may order antihypertensive medications or dialysis before a biopsy.
PROCEDURE. Immediately before a percutaneous biopsy, the nurse asks the client to void to decrease the possibility of puncturing the bladder. The left kidney is biopsied because it is closer to the skin and is not near the liver. The exact position of the kidney is determined via fluoroscopic or ultrasonographic examination or by radionuclide scan. In some clients the nephrologist may locate the kidney by using landmarks from previous images. In other clients the closed biopsy is performed directly during fluoroscopy or ultrasonographic examination.
For a closed biopsy, the client is placed in a prone position. A roll of padding is placed under the client’s abdomen to angle the kidney closer to the skin. The skin is prepared and draped, and a local anesthetic is injected. The depth of the kidney is identified by inserting a thin-gauge spinal needle. Movement of the spinal needle with breathing helps to determine that the capsule of the kidney has been located. A specially designed trocar is inserted in the path established by the spinal needle. While the client holds his or her breath, tissue is obtained by inserting the biopsy needle through the trocar and capsule into the kidney cortex. Automated spring-loaded and smaller biopsy needles have improved the tissue samples obtained. Ideally, three tissue specimens are obtained.
FOLLOW-UP CARE. After a closed percutaneous biopsy, the major risk is bleeding from the biopsy site. For 24 hours after the biopsy, the nurse monitors the dressing site, vital signs, urinary output, hemoglobin level, and hematocrit (as for postarteriography protocols). Even if the dressing is dry and there is no hematoma, the client could be bleeding from the site. An internal bleed is not readily visible but is suspected with flank pain, decreasing blood pressure, decreasing urine output, or other signs of hypovolemia or shock.
The client follows a plan of strict bedrest, lying in a supine position with a back roll for additional support for at least 6 hours after the biopsy. The head of the bed may be elevated, and the client may resume oral intake of food and fluids. After 6 hours, the client may have limited bathroom privileges if there is no evidence of bleeding.
The nurse monitors for hematuria, the most common complication of a percutaneous renal biopsy. Hematuria occurs microscopically in almost all clients, whereas 5% to 9% have gross hematuria. This problem usually resolves spontaneously 48 to 72 hours after the biopsy but can persist for 2 to 3 weeks. In rare cases, transfusions and surgery are required. There should be no obvious blood clots in the urine.
The client may have some local discomfort after the percutaneous renal biopsy. If aching originates at the biopsy site and begins to radiate to the flank and around the front of the abdomen, the nurse suspects an onset of bleeding or the development of a perinephric hematoma. This pattern of discomfort with bleeding occurs because blood in the perirenal tissues and musculature increases pressure on local nerve tracts.
If bleeding occurs, IV fluid, packed red blood cells, or both may need to be administered to restore blood pressure. In general, a small amount of bleeding creates enough pressure to compress bleeding sites; this is called a tamponade effect. If tamponade does not occur and bleeding becomes extensive, surgical intervention for hemostasis or eveephrectomy may be necessary. A perinephric hematoma may become infected, requiring treatment with antibiotics and surgical drainage.
If no bleeding occurs, the client can resume general activities after 24 hours. The nurse instructs him or her to avoid lifting heavy objects, exercising, or performing other strenuous
activities for 1 to 2 weeks after the biopsy procedure. Driving may also be restricted.
CLIENT PREPARATION. The nurse explains to the client that a kidney scan is performed to provide general information about renal blood flow. A small amount of radioactive material, a radionuclide, is used. The nurse reassures the client that there is generally no danger from the small amount of radioactive material present in the agent.
PROCEDURE. For a kidney scan, the radionuclide is injected intravenously. After injection, the radionuclide is absorbed into kidney tissue and gives off low-level radioactive emissions (scintillations). The amount of emission is measured by a scintillator or a scintillation counter. A specially designed camera records the emissions and produces an image. At the same time, the rate and location of the emissions are recorded by computer, and information about renal blood flow, or glomerular filtration, is provided.
In some cases captopril (Capoten), an antihypertensive agent, is administered at the start of the procedure to change blood flow in the kidney. This procedure is known as a Captopril Renal Scan. The drug can cause severe hypotension during and after the procedure.
FOLLOW-UP CARE. If the client is able, urination into a commode is acceptable without risk from the small amount of radioactive material to be excreted. If the client is incontinent, the nurse changes the bed linens promptly and wears gloves to maintain standard precautions. If captopril was used during the procedure, the client’s blood pressure is assessed frequently. The client is cautioned about rapid position changes and the risk for falling associated with orthostatic (positional) hypotension.
§ Ultrasonography
CLIENT PREPARATION. The nurse informs the client that ultrasonography does not cause discomfort and is without risk. This test involves applying sound waves to structures of different densities to produce images of the kidneys, ureters, and bladder and surrounding tissues. Ultrasonography allows assessment of kidney size, cortical thickness, and status of the calices. The test can be used to identify obstruction in the urinary tract, tumors, cysts, and other masses without the use of nephrotoxic contrast material (dye).
PROCEDURE. The client undergoing renal ultrasound is usually placed on a table in a prone position. A sono-graphic gel is applied to the skin over the back and flank areas to promote the conduction of sound waves. A transducer in contact with and moving across the skin delivers sound waves and measures the echoes. Images of the internal structures are produced.
FOLLOW-UP CARE. Skin care to remove the gel is all that is necessary after ultrasonography.
• OTHER URINARY TRACT
DIAGNOSTIC TESTS I Cystoscopy and Cystourethroscopy
CLIENT PREPARATION. Cystoscopy and cystourethroscopy are considered operative procedures and thus require completion of a preoperative checklist and an informed consent statement. The nurse provides a complete description of and reasons for the procedure. Cystoscopy may be performed for diagnosis or treatment. Diagnostic indications include examination for bladder trauma (cystoscopy) or urethral trauma (cystourethroscopy) and identification of the causes of urinary tract obstruction from stones or tumors. Cystoscopy may be indicated to remove bladder tumors or an enlarged prostate gland.
Cystoscopy may be performed under general or local anesthesia with sedation. The client’s age, general health, and expected duration of the procedure are some of the considerations in the decision about anesthesia. A light evening meal may be eaten. Usually the client is on NPO status after midnight on the night before the cystoscopy. A bowel preparation with laxatives or enemas is performed the evening before the procedure.
PROCEDURE. The cystoscopic examination is performed in a specially designed cystoscopic examination room. If the procedure is performed in a surgical suite under general anesthesia, traditional surgical support personnel are present. This procedure is more often performed in outpatient settings, such as a clinic, an ambulatory surgery or short-procedure unit, or a urologist’s office.
The client is assisted onto a table and, after sedation, is placed in the lithotomy position. After the administration of anesthesia, skin cleaning, and draping, a cystoscope is inserted via the urethra into the urinary bladder. If visualization of the urethra is also indicated, a urethroscope is used. Examinations commonly include the use of both the cystoscope and the urethroscope.
FOLLOW-UP CARE. After cystoscopic examination with general anesthesia, the client is returned to a postanes-thesia care unit (PACU) or area. If local anesthesia and sedation were used, the client may be returned directly to the hospital room. Clients undergoing cystoscopic examinations as outpatients are transferred to an area for monitoring before discharge to home. The nurse monitors the client for airway patency and breathing, alterations in vital signs (including temperature), and changes in urine output. The nurse also observes for the complications of bleeding and infection.
A catheter may or may not be present after cystoscopy. The client without a catheter has urinary frequency due to irritation from the catheter. The urine may be pink tinged, but gross bleeding is not expected. Bleeding or the presence of clots may obstruct the catheter and decrease urine output. The nurse monitors urine output and notifies the physician of obvious blood clots or a decreased or ceased urine output. The Foley catheter is irrigated with sterile saline, as ordered. The physician is notified if the client has a fever (with or without chills) or an elevated white blood cell (WBC) count, which suggests infection. The client is encouraged to take oral fluids
to promote adequate urine output (which helps prevent clotting) and to reduce the burning sensation on urination.
1 Retrograde Procedures
CLIENT PREPARATION. The client is prepared for retrograde procedures (retrograde pyelography, retrograde cystography, and retrograde urethrography) in a manner similar to that for the cystoscopic examination. Retrograde means going against the normal flow of urine. The nurse explains that a retrograde examination of the ureters and pelves (pyelogram), the bladder (cystogram), and the urethra (ure-throgram) involves the direct injection of radiopaque contrast medium (dye) into the lower urinary tract. Because the dye is instilled directly to obtain an outline of the structures desired, the dye does not enter the bloodstream. Therefore the client is not at risk for dye-induced acute renal failure or a systemic allergic response.
PROCEDURE. Retrograde films are obtained during the cystoscopic examination. After placement of the cystoscope by the urologist, catheters are placed into each ureter, and contrast medium is instilled into each ureter and renal pelvis. The catheters are removed by the urologist, and films are taken by the radiology technician to outline these structures as the dye is excreted. The procedure identifies any obstruction or structural abnormality.
For clients undergoing retrograde cystoscopy or urethrography, contrast medium is instilled similarly into the bladder or urethra. Cystography and urethrography also identify structural abnormalities, such as fistulas, diverticula, and tumors.
FOLLOW-UP CARE. After retrograde procedures, the nurse monitors the client for the development of infection as a result of instrumentation of the urinary tract. Because these procedures are performed during cystoscopic examination, follow-up care is the same as that for cystoscopy.
В Urodynamic Studies
Urodynamic studies describe the processes of voiding and include the following:
s Tests of bladder capacity, pressure, and tone
• Studies of urethral pressure and urine flow
* Examination of the function of perineal voluntary muscles
These tests are often used along with excretory urographic or cystoscopic procedures to evaluate problems with urine flow.
■ CYSTOMETROGRAPHY
CLIENT PREPARATION. The nurse explains that the purpose of a cystometrogram (CMG) is to determine the effectiveness and sensitivity of the bladder wall (detrusor) muscle. Determinations about bladder capacity, bladder pressure, and voiding reflexes may be made with these measurements of detrusor muscle quality. A urinary catheter may be needed temporarily during the procedure.
PROCEDURE. The nurse asks the client to void normally. The nurse records measurements of the amount, rate of flow, and time of voiding. A urinary catheter is inserted to measure the residual bladder urine volume. The cystometer is attached to the catheter, and fluid is instilled via the catheter into the bladder. The point at which the client first notes a feeling of the urge to void and the point at which the client notes a strong urge to void are recorded. Bladder capacity and bladder pressure readings are recorded graphically. The client is asked to void when the bladder instillation is complete (about 500 mL). The urinary residual after voiding is noted, and the catheter is removed. Electromyography of the perineal muscles may also be performed during the cystometric examination.
FOLLOW-UP CARE. As with any instrumentation of the urinary tract, the nurse monitors for infection. The client’s temperature, the characteristics of the urine, and the amount of urine output are recorded.
URETHRAL PRESSURE PROFILE
CLIENT PREPARATION. The nurse explains that a urethral pressure profile (also called a urethral pressure pro-filometry [UPP]) can provide information about the nature of urinary incontinence or urinary retention. A urinary catheter may be temporarily placed during the procedure.
PROCEDURE. A special catheter with pressure-sensing capabilities is inserted into the bladder. Variations in the pressure of the smooth muscle of the urethra are recorded as the catheter is slowly withdrawn.
FOLLOW-UP CARE. As with other studies involving instrumentation of the urinary tract, the client is monitored for the development of infection.
ELECTROMYOGRAPHY
CLIENT PREPARATION. The nurse explains that electromyography (EMG) of the perineal muscles may be useful in evaluating the strength of the muscles used in voiding. This information may assist in identifying methods of improving continence. The nurse informs the client that some temporary discomfort may accompany placement of the electrodes.
PROCEDURE. In EMG of the perineal muscles, electrodes are placed in either the rectum or the urethra to measure muscle contraction and relaxation.
FOLLOW-UP CARE. After the completion of EMG, the nurse administers analgesics to promote the client’s comfort. Any discomfort is usually mild and of short duration.
URINE STREAM TEST
CLIENT PREPARATION. The nurse explains that a urine stream test evaluates pelvic muscle strength and the effectiveness of pelvic muscles in interrupting the flow of urine. It is useful in evaluating urinary incontinence.
PROCEDURE. Three to five seconds after urination begins, the examiner gives the client a signal to stop urine flow. The length of time required to interrupt the flow of urine is recorded.
