Perioperative management of pheochromocytoma

Pheochromocytoma crisis: the use of magnesium sulfate

Pheochromocytoma crisis is a rare life-threatening event that may appear with a variety of clinical symptoms. We present three cases of life-threatening crisis in which magnesium sulfate was particularly beneficial in controlling symptoms and signs when more conventional forms of therapy had failed. Two patients presented with hypertensive encephalopathy, and the third presented with catecholamine-induced cardiomyopathy. All three patients successfully underwent tumor excision with magnesium sulfate used as the sole drug for control of hemodynamic disturbances during surgery. The problems of pheochromocytoma crisis and the potential benefits of magnesium sulfate in this condition are reviewed.

Undiagnosed pheochromocytoma: the anesthesiologist nightmare

A male, 62 years of age, presented to the operating room for the removal of a right adrenal mass. Induction of anesthesia triggered a severe hypertensive crisis resistant to high doses of nitroprusside, nitroglycerin and labetalol. The crisis was ultimately resolved with the administration of 5 mg bolus of phentolamine. Surgery was canceled, the patient was transported to the intensive care unit with a continuous drip of phentolamine. High urinary and plasma catecholamines suggested the presence of pheochromocytoma. Three weeks of oral phenoxybenzamine therapy subsequently allowed uneventful induction of anesthesia and open adrenalectomy. Pathologic examination of the resected adrenal tissue confirmed the presence of pheochromocytoma. Anesthetic drugs can exacerbate the life-threatening cardiovascular effects of catecholamines secreted by pheochromocytomas. Treating patients preoperatively with alpha-adrenergic blockade is helpful for reducing intraoperative hypertensive episodes. Postoperative administration of inotropic agents to correct hypotension due to catecholamine withdrawal may be required. Management of patients with pheochromocytoma remains a challenge for the anesthesiologist, despite the advent of new drugs and techniques.