Pediatric emergency medicine trisk 1886 1886
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Consider CAH as etiology of ill-appearing neonate; recognize importance of quickly
visualizing genitalia and obtaining point-of-care blood glucose.
Initial Assessment/H&P
The appearance of symptoms of salt-wasting crisis can be insidious, with a history of poor
feeding, lack of weight gain, lethargy, irritability, and vomiting. The nonspecific symptoms
may lead to consideration of diagnoses other than CAH and delay initiation of treatment.
Examination of the child should include the vital signs and an assessment of the degree of
dehydration. In severe cases, there may be shock and metabolic acidosis. The genitalia should
be examined carefully because the degree of ambiguity of the genitalia varies considerably.
Virilized females may have an enlarged clitoris and fusion of the labial folds. An
undervirilized male may have a small phallus and/or hypospadias. The presence of gonads in
the inguinal canals or labioscrotal fold is suggestive of a male karyotype. Hyperpigmentation
of the labioscrotal folds and the nipples is occasionally present in the neonatal period;
however, it is rarely prominent enough to alert the examiner to the possibility of CAH.
Management/Diagnostic Testing
In the ED, the most urgent investigations are plasma electrolytes and blood glucose. The
combination of hyperkalemia and hyponatremia is often the first clue to the diagnosis of CAH,
especially in males. The plasma potassium is elevated, but in the presence of vomiting and
diarrhea, the rise may be blunted. Potassium levels between 6 and 12 mEq/L are occasionally
encountered, and can paradoxically be seen without any clinical cardiac dysfunction or ECG
changes. The plasma bicarbonate level is usually low, reflecting the metabolic acidosis that
results from the retention of hydrogen ions in exchange for sodium loss. The blood glucose is
usually normal; however, hypoglycemia may occur secondary to the lack of cortisol and the
reduced caloric intake during the acute illness. Serum should be drawn for determination of an
adrenal steroid profile to include cortisol, 17-hydroxyprogesterone, dehydroepiandrosterone,
androstenedione, testosterone, and if possible, ACTH. Ideally, blood should be obtained for
these tests before the administration of hydrocortisone. For the child in crisis, the diagnosis
must be based on physical findings and electrolyte abnormalities, and treatment must be
instituted before the definitive results of the adrenal steroid profile are available.
Emergency glucocorticoid therapy, delivered at the stress dose of hydrocortisone 50
mg/m2/day should be administered to any patient with known CAH or other form of adrenal
insufficiency in the setting of temperature above 38.5°C, emesis and/or diarrhea, bony fracture
of any type, or in the setting of altered mental status or shock. If the patient appears ill, an
initial dose of hydrocortisone 50 mg/m2 may be given either intramuscularly or intravenously,
followed by that dose divided in four and given every 6 hours. If the patient is not illappearing and is tolerating oral fluids and medications, their usual daily dose may be tripled
and given in three equal parts daily, or hydrocortisone 50 mg/m2/day may be given orally in
three equal parts daily if the home dose cannot be readily established.
Correction of Hyperkalemia, Hypoglycemia, and Acidosis
Infants with CAH tolerate hyperkalemia far better than do older children and adults, with
potassium levels as high as 12 mEq/L reported without clinical signs. Volume restoration
