Pediatric emergency medicine trisk 1888 1888
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Clinical Considerations
Clinical Recognition
The detection of a pheochromocytoma requires expert clinical awareness. Most patients are
symptomatic, but the symptoms are episodic, nonspecific and, in the child, are likely to be
attributed to other disease entities. The symptoms and signs are related to the excess
production of catecholamines and can be explained on the basis of the pharmacologic effects
of these substances. Up to one-third of pheochromocytomas are associated with familial
syndromes.
The most common symptoms are headache, palpitations, and excessive or inappropriate
sweating. The headache, characteristically, is pounding and may be severe and associated with
altered mental status. The palpitations may be accompanied by tachycardia. Almost all patients
will have one of the three symptoms listed, and most will have at least two. Other symptoms
may include nervousness, tremor, fatigue, chest or abdominal pains, and flushing.
Because the hypertension may be continuous or paroxysmal, frequent and repeated blood
pressure determinations may be necessary. Hypertension is most likely to be found when the
patient is symptomatic. A hypertensive patient who is asymptomatic is unlikely to have a
pheochromocytoma.
Triage
The most useful screening tool for pheochromocytoma is the blood pressure cuff because most
pheochromocytomas are associated with hypertension.
Initial Assessment/H&P
Paroxysmal symptoms and hypertension should lead to consideration of this diagnosis. The
diagnosis of a pheochromocytoma should also be considered in patients with malignant
hypertension, in those who fail to respond or respond inappropriately to antihypertensive
medications, and in those who develop hypertension during the induction of anesthesia or
during surgery. Incidence of pheochromocytomas is increased among patients with
neurofibromatosis and with the multiple endocrine neoplasia syndrome types II and III.
Management/Diagnostic Testing
Documentation of excess catecholamine in either the urine or serum confirms the diagnosis of
pheochromocytoma. Plasma metanephrine concentration has now been shown to be a superior
screening and confirmatory test, and is now widely available. Historical tests are still
commonly used and have confirmatory value including the measurement of urinary
catecholamines or their metabolites (3-methoxy-4-hydroxymandelic acid and total
metanephrines) in a 24-hour urine collection accompanied by a patient symptom log. The
finding of significant elevations of these substances is adequate confirmatory data. Some falsenegative results may occur using urinary catecholamines. When the degree of suspicion is
high, repeated specimens may be needed.
Once the diagnosis is confirmed, anatomic localization is necessary using either computed
tomography or nuclear magnetic resonance imaging. Occasionally, arteriography with
selective sampling for epinephrine production is necessary for localization. Cure is by the
surgical removal of the tumor.
