Lecture 3. First aid for life-threatening conditions in children (acute respiratory, cardiovascular failure, hyperthermia, seizure syndromes, hemorrhagic syndrome).
Respiratory failure occurs when there is an impairment of gas exchanges in your body. This means that your lungs are unable to get enough oxygen to your blood, when they are unable to remove enough carbon dioxide from your blood, or both. “Enough” oxygen is defined as 6.7 kPa (kilopascals, a unit of pressure) or more; and “enough” carbon dioxide removed is defined as 6.7 kPa or less. A pulse oxymetry (amount of oxygenation in the blood) below 90 percent is considered critical. Acute respiratory failure is when respiratory failure comes on suddenly and lasts for a short time, as opposed to chronic respiratory failure, which is an ongoing condition.
Respiratory failure can be caused by conditions that affect your breathing, such as spinal injuries that damage the nerves controlling your breathing or diseases, such as chronic obstructive pulmonary disease, which prevents enough air from moving through your airways.
Symptoms of respiratory failure include rapid breathing, shortness of breath, air hunger (feeling like you can’t get as much air as you need) and in severe cases, blue skin, lips and fingernails, confusion and drowsiness.
In order to treat respiratory failure, doctors must get enough oxygen to your organs, remove the carbon dioxide from your body, and treat whatever is causing the condition. Oxygen therapy is helpful in patients who are not getting enough oxygen, but it will not resolve the problem of a patient whose body is not effectively removing carbon dioxide. Either way, you will probably need to be admitted to an intensive care unit for treatment because acute respiratory failure is considered a medical emergency.
In acute respiratory failure supportive care usually involves giving oxygen. Guidelines recommend that all primary care centres have emergency oxygen and pulse oximetry monitoring. But oxygen delivery itself can be a source of concern as it may cause harm in patients at risk of hypercapnoea. How much oxygen to give can be summed up simply: give enough.
For critically ill patients, high flow oxygen via a face mask with a reservoir bag should be given immediately, while waiting for emergency assistance. In other patients, peripheral blood oxygen saturations should be used to titrate therapy.
If levels are above the target saturation then oxygen delivery should be reduced. Normal target saturations are 94-98 per cent in patients who are not at risk of hypercapnoea.
In patients known to have COPD or some other predisposition to hypercapnoea, such as neuromuscular weakness or morbid obesity, a target saturation of 88-92 per cent should be used.
Supportive care for the patient also involves providing reassurance. Keeping calm is important for both practitioner and patient. An overlay of anxiety will exacerbate symptoms and make ventilation less effective by increasing dead-space ventilation.
Heart failure is a syndrome in which the heart pumps insufficient oxygenated blood to meet the metabolic needs of the tissues, or can do so only from an elevated filling pressure. Maximal oxygen utilization is thus reduced in proportion to the degree of heart failure
Heart failure may be left-sided, in which pulmonary edema is a predominant symptom, or right-sided, often with hepatomegaly and systemic edema. In many instances, both sides of the heart are involved. Exercise intolerance and fatigue are common in all patients
Heart failure may also be characterized as systolic and/or diastolic. In systolic heart failure, the left ventricular ejection fraction is reduced. In diastolic heart failure, the left ventricle systolic function typically is preserved, but the altered ventricle compliance results in a high filling pressure. This distinction should be made during the diagnostic evaluation because the two conditions have different prognoses and may respond differently to treatment
mmediate action
A patient in respiratory distress with acute pulmonary edema is a medical emergency and requires immediate treatment to:
Decrease the pulmonary capillary venous pressure
Reverse alveolar fluid accumulation
Restore normal arterial oxygenation
Oxygen is given to achieve an arterial oxygen saturation > 90%. Ventilation is improved with the patient sitting up rather than recumbent; allowing the legs to be dependent helps reduce pulmonary capillary pressure. Early use of ‘bipap‘ pressure support can often avoid the need for intubation.
Prompt decreases in pulmonary capillary pressure can be achieved with:
Sublingual nitrates administered every few minutes, with close attention to arterial blood pressure and the patient’s respiratory status
Intravenous nitrates; however, the intravenous route requires more time for up titration than the sublingual route
Intravenous morphine; also decreases systemic vascular resistance
Intravenous nesiritide
Intravenous furosemide or bumetanide; however, the onset of action may take at least 15 minutes
Urgent action
Severe heart failure or heart failure that has suddenly developed or suddenly worsened is a potential emergency that requires hospital admission and aggressive medical therapy.
Hyperthermia is the general name given to a variety of heat-related illnesses.
Warm weather and outdoor activity go hand in hand. However, it is important for older people to take action to avoid the severe health problems often caused by hot weather.
Causes and Risk Factors of Hyperthermia
Regardless of extreme weather conditions, the healthy human body keeps a steady temperature of 98.6 degrees Fahrenheit.
In hot weather or during vigorous activity, the body perspires. As this perspiration evaporates from the skin, the body is cooled.
If challenged by long periods of intense heat, the body may lose its ability to respond efficiently. When this occurs, a person may experience hyperthermia. In other words, hyperthermia occurs when body metabolic heat production or environmental heat load exceeds normal heat loss capacity or when there is impaired heat loss.
Health Factors That Increase Risk
The temperature does not have to hit 100 degrees for a person to be at risk. Both one’s general health and/or lifestyle may increase a person’s chance of suffering a heat-related illness.
Health factors which may increase risk include:
poor circulation
inefficient sweat glands, and changes in the skin caused by the normal aging process heart, lung and kidney diseases, as well as any illness that causes general weakness or fever high blood pressure or other conditions that require changes in diet.
For example, people on salt-restricted diets may increase their risk of being unable to perspire, caused by medications including diuretics, sedatives and tranquilizers, and certain heart and blood pressure drugs.
Other factors include being substantially overweight or underweight, and drinking alcoholic beverages.
Lifestyle factors that can increase risk are:
· unbearably hot living quarters
· lack of transportation – which prevents people from seeking respite from the heat in shopping malls, movie houses, and libraries
· overdressing – because they may not feel the heat, older people may not dress appropriately in hot weather
· visiting overcrowded places – trips should be scheduled during non-rush hour times
· not understanding weather conditions – older persons at risk should stay indoors on especially hot days.
Symptoms of Hyperthermia
The two most common forms of hyperthermia are heat exhaustion and heat stroke. Of the two, heat stroke is especially dangerous and requires immediate medical attention.
Heat stress occurs when a strain is placed on the body as a result of hot weather.
Heat fatigue is a feeling of weakness brought on by high outdoor temperature. Symptoms include cool, moist skin and a weakened pulse. The person many feel faint.
Heat syncope is a sudden dizziness experienced after exercising in the heat. The skin appears pale and sweaty but is generally moist and cool. The pulse is weakened and the heart rate is usually rapid. Body temperature is normal.
Heat cramps are painful muscle spasms in the abdomen, arms or legs following strenuous activity. Heat cramps are caused by a lack of salt in the body.
Heat exhaustion is a warning that the body is getting too hot. The person may be thirsty, giddy, weak, uncoordinated, nauseated and sweating profusely. The body temperature is normal and the pulse is normal or raised. The skin is cold and clammy.
Heat stroke can be life-threatening and victims can die. A person with heat stroke usually has a body temperature above 104 degrees Fahrenheit. Other symptoms include confusion, combativeness, bizarre behavior, faintness, staggering, strong and rapid pulse, and possible delirium or coma. High body temperature is capable of producing irreversible brain damage.
Treatment of Hyperthermia
If the victim is exhibiting signs of heat stroke, emergency assistance should be sought immediately. Without medical attention, heat stroke can be deadly.
Heat exhaustion may be treated in several ways:
· get the victim out of the sun into a cool place, preferably one that is air conditioned
· offer fluids but avoid alcohol and caffeine – water and fruit juices are best
· encourage the individual to shower and bathe, or sponge off with cool water
· urge the person to lie down and rest, preferably in a cool place
A seizure is an abnormal, unregulated electrical discharge that occurs within the brain’s cortical gray matter and transiently interrupts normal brain function. A seizure typically causes altered awareness, abnormal sensations, focal involuntary movements, or convulsions (widespread violent involuntary contraction of voluntary muscles).
About 2% of adults have a seizure at some time during their life. Two thirds of these people never have another one.
Definitions: Terminology can be confusing.
Epilepsy (also called epileptic seizure disorder) is a chronic brain disorder characterized by recurrent (≥ 2), unprovoked seizures (ie, not related to reversible stressors). Epilepsy is often idiopathic, but various brain disorders, such as malformations, strokes, and tumors, can cause symptomatic epilepsy.
Nonepileptic seizures are provoked by a temporary disorder or stressor (eg, metabolic disorders, CNS infections, cardiovascular disorders, drug toxicity or withdrawal). In children, fever can provoke a seizure (see Neurologic Disorders in Children: Febrile Seizures).
Symptomatic seizures are due to a known cause (eg, brain tumor, stroke). Symptomatic seizures are most common among neonates (see Neurologic Disorders in Children: Neonatal Seizure Disorders) and the elderly.
Psychogenic seizures (pseudoseizures) are symptoms that simulate seizures in patients with psychiatric disorders but that do not involve an abnormal electrical discharge in the brain.
Etiology
Common causes of seizures (see Table 1: Seizure Disorders: Causes of Seizures) vary by age of onset:
Before age 2: Developmental defects, birth injuries, and metabolic disorders
Ages 2 to 14: Idiopathic seizure disorders
Adults: Cerebral trauma, alcohol withdrawal, tumors, strokes, and unknown cause (in 50%)
The elderly: Tumors and strokes
In reflex epilepsy, a rare disorder, seizures are triggered predictably by an external stimulus, such as repetitive sounds, flashing lights, video games, or even touching certain parts of the body.
Symptoms and Signs
Seizures may be preceded by an aura. Auras may consist of sensory, autonomic, or psychic sensations (eg, paresthesias, a rising epigastric sensation, abnormal smells, a sensation of fear, a déjà vu sensation).
Most seizures end spontaneously in 1 to 2 min. Generalized seizures are often followed by a postictal state, characterized by deep sleep, headache, confusion, and muscle soreness; this state lasts from minutes to hours. Sometimes the postictal state includes Todd’s paralysis (a transient neurologic deficit, usually weakness, of the limb contralateral to the seizure focus).
Most patients appear neurologically normal between seizures, although high doses of the drugs used to treat seizure disorders, particularly anticonvulsants, can reduce alertness. Any progressive mental deterioration is usually related to the neurologic disorder that caused the seizures rather than to the seizures themselves. Rarely, seizures are unremitting.
Partial seizures: There are several types of partial seizures.
Simple partial seizures cause motor, sensory, or psychomotor symptoms without loss of consciousness. Specific symptoms reflect the affected area of the brain (see Table 2: Seizure Disorders: Manifestations of Partial Seizures by Site). In jacksonian seizures, focal motor symptoms begin in one hand, then march up the arm. Other focal seizures affect the face first, then spread to an arm and sometimes a leg. Some partial motor seizures begin with an arm raising and the head turning toward the moving arm.
Tonic seizures occur most often during sleep, usually in children. The cause is usually the Lennox-Gastaut syndrome. Tonic (sustained) contraction of axial muscles may begin abruptly or gradually, then spread to the proximal muscles of the limbs. Tonic seizures usually last 10 to 15 sec. In longer tonic seizures, a few, rapid clonic jerks may occur as the tonic phase ends.
Tonic-clonic seizures may be primarily or secondarily generalized. Primarily generalized seizures typically begin with an outcry; they continue with loss of consciousness and falling, followed by tonic contraction, then clonic (rapidly alternating contraction and relaxation) motion of muscles of the extremities, trunk, and head. Urinary and fecal incontinence, tongue biting, and frothing at the mouth sometimes occur. Seizures usually last 1 to 2 min. There is no aura. Secondarily generalized tonic-clonic seizures begin with a simple partial or complex partial seizure.
Myoclonic seizures are brief, lightning-like jerks of a limb, several limbs, or the trunk. They may be repetitive, leading to a tonic-clonic seizure. The jerks may be bilateral or unilateral. Unlike other seizures with bilateral motor movements, consciousness is not lost unless the myoclonic seizure progresses into a generalized tonic-clonic seizure.
Juvenile myoclonic epilepsy is an epilepsy syndrome characterized by myoclonic, tonic-clonic, and absence seizures. It typically appears during adolescence. Seizures begin with a few bilateral, synchronous myoclonic jerks, followed in 90% by generalized tonic-clonic seizures. They often occur when patients awaken in the morning, especially after sleep deprivation or alcohol use. Absence seizures may occur in one third of patients.
Febrile seizures occur, by definition, with fever and in the absence of intracranial infection; they are considered a type of provoked seizure. They affect about 4% of children aged 3 mo to 5 yr (see Neurologic Disorders in Children: Febrile Seizures). Benign febrile seizures are brief, solitary, and generalized tonic-clonic in appearance. Complicated febrile seizures are focal, last > 15 min, or recur ≥ 2 times in < 24 h. Overall, 2% of patients with febrile seizures develop a subsequent seizure disorder. However, incidence of seizure disorders and risk of recurrent febrile seizures are much greater among children with complicated febrile seizures, preexisting neurologic abnormalities, onset before age 1 yr, or a family history of seizure disorders.
Treatment
Elimination of the cause if possible
Avoidance of or precautions during situations when loss of consciousness could be life threatening
Drugs to control seizures
Surgery if ≥ 2 drugs do not control seizures
Optimal treatment is to eliminate the causes whenever possible. If the cause cannot be corrected or identified, anticonvulsants are often required, particularly after a 2nd seizure; usefulness of anticonvulsants after a single seizure is controversial, and risks and benefits should be discussed with the patient. Because the risk of a subsequent seizure is low, drugs may be withheld until a 2nd seizure occurs, particularly in children. In children, certain anticonvulsants cause important behavior and learning problems.
During a generalized tonic-clonic seizure, injury should be prevented by loosening clothing around the neck and placing a pillow under the head. Attempting to protect the tongue is futile and likely to damage the patient’s teeth or the rescuer’s fingers. Patients should be rolled onto their left side to prevent aspiration. These measures should be taught to the patient’s family members and coworkers.
Because partial seizures can become generalized, patients are at risk of losing consciousness and thus should be advised to take certain precautions. Until seizures are controlled, patients should refrain from activities in which loss of consciousness could be life threatening (eg, driving, swimming, climbing, operating power tools, bathing in a bathtub). After seizures are completely controlled (typically for > 6 mo), many such activities can be resumed if appropriate safeguards (eg, lifeguards) are used, and patients should be encouraged to lead a normal life, including exercise and social activities. In a few states, physicians must report patients with seizures to the Department of Motor Vehicles. However, most states allow automobile driving after patients have been seizure-free for 6 mo to 1 yr.
Disseminated intravascular coagulation (DIC)
DIC is the net effect of the consumption of coagulation factors due to intravascular activation of coagulation factors and subsequent fibrinolysis. The balance between coagulation and fibrinolysis may produce either thrombosis or hemorrhage, respectively. Hemorrhage is also the result of consumption of factors used in intravascular coagulation. DIC is always associated with a primary serious illness: sepsis, asphyxia-hypoxia, trauma, shock, burns, heart stroke, snake bites, transfusion reaction, malignancy. In each condition, various factors produce endothelial injury, tissue release of thromboplastin or procoagulant factors.
The diagnosis of DIC depends on clinical and laboratory evidence of disseminated coagulation and consumption of clotting factors. In an acutely ill patient, the sudden onset of bleeding from venipuncture or incision sites, gastrointestinal or pulmonary hemorrhage, petechiae, ecchymosis, and symmetric peripheral gangrene (thrombosis) suggest the diagnosis of DIC. Laboratory evidence of DIC:
– Prolonged prothrombin, partial thromboplastin and thrombin time;
– Thrombocytopenia;
– Low fibrinogen, factors V and VII;
– Elevated fibrin degradation (split) products.
Treatment of DIC is directed toward administering the specific therapy for the
underlying disorder, such as oxygen for hypoxia, antibiotics for sepsis, and fluids for
shock. replacement of depleted blood, coagulation factors and platelets is indicated
with severe bleeding. Heparin may be useful in the presence of significant
thrombosis.
Henoch-Schonlein purpura (HSP)
This is the most common vasculitis of childhood and is characterized by palpable nonthrombocytopenic purpura; periarticular, scrotal swelling, edema and inflammation; gastrointestinal bleeding and nephritis. The cutaneous manifestations are striking, with circular purpuric lesions 2-3cm in size typically occurring over the buttocks and the posterior surfaces of the arms and legs. Skin lesions and the renalglomeruli contain IgA immune complexes.
Clinical manifestations. The onset of the illness often follows a nonspecific upper respiratory tract infection in a 4-10 yr old child. The skin lesions are the hallmark of the disease, but cramping, intermittent abdominal pain, periarticular swelling and scrotal edema may be present. Glomerulonephritis is common within 1-2 months of onset and becomes manifest as asymptomatic hematuria, with or without proteinuria.
5% have acute renal insufficiency, while another 5% have a slow progression with renal failure developing months to years later.
Most patients recover without therapy, but a small percentage relapse and another small group has a much slower rate of recovery accompanied by the persistence of hematuria for 1-2 yr.
Treatment. Therapy is symptomatic because 90% of patients have a self-limited illness. NSAIDs and drugs for platelet desegregation (Dipiridamol) are useful. Corticosteroids may relieve abdominal pain and joint edema, but this has not been proved in controlled studies. Steroids do not have a beneficial effect on renal disease.
Adrenal Insufficiency In Children
Adrenal insufficiency is a condition that develops when your child’s adrenal glands do not make enough adrenal hormones. Adrenal hormones such as cortisol help your child’s body handle stress, keep blood pressure normal, and balance salt and fluids. They control how his body uses sugars, fats, and proteins. An adrenal crisis may happen if your child’s adrenal hormones become too low. This condition is life-threatening and needs immediate treatment.
Causes of adrenal insufficiency in children:
Autoimmune disorders: A problem with your child’s immune system may make his body attack his adrenal glands.
Injury: Injury to your child’s adrenal glands may make them bleed, which can prevent the production of adrenal hormones. Trauma may happen when a mother has trouble giving birth to her child. Ask your child’s caregiver for more information about causes of adrenal bleeding.
Genetic conditions: Your child may have been born with genes that caused the condition. Your child’s risk of adrenal insufficiency is greater if he has a family member with this type of genetic condition.
Infections: Your child’s adrenal glands may be damaged by certain infections.
Medicines: Certain medicines may cause adrenal insufficiency. Long-term treatment with steroid medicines for other conditions commonly causes adrenal insufficiency. This may be temporary or permanent. Ask your child’s caregiver if any of the medicines your child takes can cause adrenal insufficiency.
Other causes: Surgery, tumors, or radiation therapy may cause damage to your child’s adrenal glands.
What are the signs and symptoms of adrenal insufficiency in children?
The signs and symptoms of adrenal insufficiency depend on child’s age.
Signs and symptoms iewborns or infants:
Weakness
Vomiting or feeding problems
Dry skin and lips
Signs and symptoms in older children:
Stomach pain, muscle weakness, or muscle pains
Tiredness, dizziness, or trouble thinking clearly
Craving salty foods, decrease in appetite, or weight loss
Decreased or absent pubic hairs
Skin color changes, especially on sun-exposed areas
Diagnosis
Blood tests: Your child’s blood is tested to measure hormone levels and to check for health problems his adrenal insufficiency may be causing.
Urine tests: Your child’s urine is tested to measure the amount of adrenal hormones it contains.
Chemical stimulation tests: Your child’s blood is tested twice in this test. The first time it is tested to measure the hormone levels. Then he is given a shot of chemicals to cause his adrenal glands to make hormones. His blood is tested a second time to see if the hormone levels increased.
Genetic screening: This may be done to see if your child has abnormal genes that are causing his condition. This will also give your child’s caregiver more information on how to treat his condition.
In the hypotensive patient, rapid restoration of intravascular volume with isotonic sodium chloride containing dextrose is needed. Additional dextrose (D25W) should be administered as required to treat hypoglycemia.
Blood should be drawn to test for cortisol, electrolyte, glucose, and ACTH levels, plasma renin activity, and aldosterone level. Measurement of urinary sodium and potassium concentrations may also be helpful in assessing mineralocorticoid status. Simultaneous with the administration of intravenous fluids, stress doses of glucocorticoid should be given. Hydrocortisone is the treatment of choice because of its mineralocorticoid activity. The recommended stress dose of hydrocortisone is 50 to 75 mg/m2 intravenously initially, followed by 50 to 75 mg/m2 per day intravenously divided in 4 doses.21 It should be recognized that recommendations for stress doses are empiric and not based on carefully controlled clinical trials. Hydrocortisone may be given intramuscularly if no intravenous access exists, but intramuscular administration works more slowly and may be ineffectively absorbed if peripheral perfusion is poor. Comparable stress doses are 10 to 15 mg/m2 for methylprednisolone and 1.5 to 2 mg/m2 for dexamethasone. The latter 2 corticosteroids have very little mineralocorticoid activity. Prednisone is not a glucocorticoid of choice, because it must be converted to prednisolone before if has glucocorticoid activity. In patients with liver failure, this conversion may be impaired.
Dexamethasone can be used if one wants to treat the patient urgently but wishes to carryout a diagnostic ACTH-stimulation test. Treatment should never be withheld if the diagnosis of adrenal insufficiency is suspected. If the patient has good gastrointestinal function, fludrocortisone (0.1 to 0.2 mg daily), a synthetic mineralocorticoid, may be administered orally. Usually, administration of intravenous sodium chloride along with large doses of hydrocortisone are sufficient to begiormalizing electrolyte abnormalities, making the addition of mineralocorticoid unnecessary in the first hours of treatment. Hydrocortisone has ∼1/400th the mineralocorticoid activity of fludrocortisone.2 Very rarely, if there is a coexisting cardiomyopathy and/or acute renal failure prohibiting rapid rehydration, more aggressive therapy of hyperkalemia may be needed. When the patient has been stabilized, is feeling well, and is eating normally, glucocorticoid dosing may be tapered to physiologic replacement doses. In the first year of life, infants with primary adrenal insufficiency are generally supplemented with 1 to
Children with possible adrenal insufficiency should be referred to a pediatric endocrinologist for further diagnostic evaluation, follow-up care, and counseling.
Physiologic Replacement Doses of Glucocorticoid
Maintenance dosing of glucocorticoid for replacement therapy is based on the secretory rate of cortisol in the intact system. However, there is debate about the baseline secretory rate, which makes it difficult to determine an exact replacement regimen. There are data indicating that the secretory rate may be as low as 5 to 6 mg/m2 per day without substantial variation with pubertal status.26–28 Because the bioavailability of cortisol is reduced by gastric acids and first pass in the liver, the usual maintenance dose for glucocorticoid replacement needs to be adjusted above the estimated secretion rate. Therefore, 9 to 12 mg/m2 per day of oral hydrocortisone is probably a reasonable initial starting dose for individuals with primary adrenal insufficiency. Patients with secondary adrenal insufficiency, which is frequently partial, may do well on a lower dose. Adjustments are subsequently made on an individual basis to avert signs and symptoms of adrenal insufficiency while also avoiding the growth retardation and Cushingoid features that can accompany overreplacement.
Cortisol (hydrocortisone) is usually the drug of choice and is dosed every 8 hours; other preparations with longer half-lives (ie, prednisone, dexamethasone) can also be used if necessary to facilitate adherence. It is more difficult to finely adjust the dosage of these more potent synthetic preparations, and some have little or no activity at the mineralocorticoid receptor, which requires an increase in mineralocorticoid replacement. Although most replacement protocols call for dividing the cortisol equally either 3 times per day or every 8 hours, some favor skewing the dose slightly toward a higher proportion being administered in the morning to attempt to mimic the normal diurnal variation of cortisol in patients with adrenal insufficiency that does not stem from CAH. In patients with CAH, there is evidence to suggest that nighttime cortisol clearance is reduced, suggesting that the hydrocortisone dose should be weighted to the morning time.29 Nevertheless, some clinicians prefer to treat CAH with a higher dose of cortisol or a longer-acting glucocorticoid at night in an attempt to suppress the early-morning ACTH-mediated adrenal androgen production.
ACTH cannot be used as a criterion for glucocorticoid dose adjustment in primary adrenal insufficiency. Attempts at achieving ACTH levels within the reference range leads to chronic overreplacement. Rather, one should gauge the quantity and timing of glucocorticoids on the basis of the patient’s own sense of well-being and energy level. Frequent headaches, lethargy, nausea, and/or abdominal pain may indicate inadequate treatment. Objective signs of inadequate replacement therapy are orthostatic pulse and/or blood pressure changes. If skin hyperpigmentation becomes apparent in primary adrenal insufficiency, obtaining plasma ACTH levels may be helpful.
Stress Dosing
The cortisol secretory rate increases substantially during physiologic stress. Consequently, all patients with adrenal insufficiency (primary or secondary) need to be educated about the need to increase their glucocorticoid dose during stress to avoid preventable episodes of adrenal crisis, which can be fatal. Patients should also be reminded to wear a medical alert bracelet or other jewelry item and to carry an emergency medical information card to ensure that medical providers know about their underlying disorder.
There is controversy as to what constitutes “stress” and the need to increase glucocorticoid doses. Mild stresses such as immunizations, uncomplicated viral illnesses, and upper respiratory tract infections with sore throat, rhinorrhea, and/ or low-grade fever and otitis media may not require use of a stress-dose steroid regimen if the patient otherwise acts and appears well. More severe stresses such as illness accompanied by fever ≥38°C, vomiting, diarrhea, inadequate oral intake, lethargy, surgery, trauma, dental work, and large burns should be accompanied by increased glucocorticoid doses to prevent the hypoglycemia, hypotension, and even cardiovascular collapse that can occur in the setting of an adrenal crisis. Moderate-to-extreme physical exercise may be facilitated by a slight increase (∼30%) in hydrocortisone dosage 60 minutes before exercise. This too, is controversial; Weise et al30 recently reported that in adolescents with CAH, an additional morning dose of hydrocortisone, which resulted in doubling of cortisol levels, did not affect performance, nor did it alter blood glucose, lactate, free fatty acids, or epinephrine levels during short-term high-intensity exercise compared with placebo. Glucose and epinephrine levels during exercise were significantly lower in patients with CAH compared with a healthy control group. This research study was performed under laboratory conditions and should not be interpreted to mean that patients with CAH should be exercise restricted. There are insufficient data as yet to draw such conclusions, and prevailing collective experience suggests that such patients are capable of vigorous physical activity without adverse consequences. In their consensus statement on CAH, the Lawson Wilkins Pediatric Endocrine Society and European Society for Paediatric Endocrinology did not recommend increasing the glucocorticoid dose during psychological and emotional stress.10
The degree to which doses should be increased is also debated, with recommendations varying between 2 and 10 times the maintenance rate.31 A common recommendation is to treat most stresses that require increased doses with hydrocortisone 30 to 50 mg/m2 per day (approximately tripling the daily dose) divided into 3 or 4 doses over the day. It is important that each patient know his or her specific stress-dose regimen, because one might need to increase the maintenance dose more substantially for an individual who is on relatively low-dose maintenance replacement for secondary adrenal insufficiency compared with an individual on relatively larger doses needed to suppress excess androgen production in the treatment of CAH.
The most severe stresses, such as major surgery or sepsis, are often treated more aggressively, with doses up to 100 mg/m2 per day divided every 6 hours intravenously. Although various glucocorticoid preparations could be used for stress dosing, hydrocortisone is the preferred agent because of its mineralocorticoid activity. In most instances, stress doses are administered for only 24 to 48 hours unless the underlying illness is prolonged.
Children who are unable to tolerate oral maintenance or stress doses during an illness require parenteral glucocorticoid administration. This is commonly initiated at home using intramuscular hydrocortisone sodium succinate at a dose of 50 mg/m2 and will provide coverage for ∼6 to 8 hours. Consultation with a health care provider is recommended. If the patient’s condition does not improve or worsens, emergency evaluation and treatment with intravenous hydrocortisone should be undertaken.
Parenteral hydrocortisone is also frequently recommended before general anesthesia and surgery. A preoperative dose of 50 mg/m2 30 to 60 minutes before induction of anesthesia can be administered intravenously or intramuscularly. A second dose of 50 mg/m2 can then be administered as a constant infusion or as an intravenous bolus divided every 6 hours over the next 24 hours. Intravenous or oral stress doses may be continued until the patient has recovered.
Bibliography
а) Basic
1. Janette B. Benson. Diseases and Disorders in Infancy and Early Childhood / Janette B. Benson Marshall M. Haith. – Academic Press, 2009 – 424 p.
2. Maureen R. Nelson. Pediatrics / Maureen R. Nelson. – NY: Demos Medical Publishing, 2010. – 259 p.
3. Vicky R. Bowden. Pediatric Nursing Procedures / Vicky R. Bowden, Cindy Smith Greenberg. –
4. Ruth McGillis Bindler. Clinical skills manual for pediatric nursing: caring for children / Ruth McGillis Bindler, Ruth C. McGillis Bindler, Jane Ball. – Pearson/Prentice Hall, 2008. -181 p.
b) Additional
