Phentolamine continuous infusion in a patient with pheochromocytoma.

Purpose: Use of continuous phentolamine infusion therapy for management of serious cardiovascular complications during adrenalectomy for pheochromocytoma is reported.

Summary: In preparation for surgical resection of a pheochromocytoma, a 38-year-old woman received outpatient oral therapy with the α-adrenergic-receptor blocker phenoxybenzamine for 25 days with the goal of reducing cardiovascular risks associated with catecholamine surge during surgery. Due to inappropriate dosage adjustment, however, outpatient phenoxybenzamine therapy did not achieve adequate α-adrenergic-receptor blockade; during the laparoscopic resection procedure, the woman developed severe hypertension, leading to cardiac arrest and discontinuation of the operation. After resuscitative measures, the patient was admitted to the surgical intensive care unit for mechanical ventilation, medical management (including intermittent bolus injections of phentolamine and a continuous i.v. infusion of esmolol for control of blood pressure and heart rate), and hemodynamic monitoring; despite those measures, cardiovascular instability persisted during the immediate postoperative period. The day after the abortive surgery attempt, a continuous infusion of phentolamine mesylate (1 mg/hr, adjusted hourly to achieve the blood pressure target) was initiated. Four days after initiation of continuous phentolamine infusion, the patient was deemed to be hemodynamically stable, and the surgery was successfully performed.

Conclusion: A continuous infusion of phentolamine was used in a patient with pheochromocytoma to control perioperative hypertensive episodes during surgical adrenalectomy.