Anesthetic management for the excision of pheochromocytoma

Anesthetic experiences involving 23 patients with pheochromocytoma during the period 1983-1986 are reported. Typical clinical symptoms and positive laboratory results were found in all patients. Epidural block was used in 11, general anesthesia in 10, and a combination of the two in 2 cases. Swan-Ganz catheter was used to monitor hemodynamic changes during anesthesia and surgery. Before excision of the tumor, a larger volume of fluid was transfused than was lost, resulting in the elevation and/or maintenance of pulmonary arterial pressure (PAP) and pulmonary capillary wedge pressure (PCWP) at the upper limit of the normal range. Once venous supply was secured, the incidence of critical hypotension following resection of the tumor was reduced significantly. But it was difficult to avoid this blood pressure drop in some cases, and intravenous infusion of catecholamines was required. After tumor excision a marked decline of myocardial function was observed. This suggests that myocardial dysfunction might be another important factor of severe hypotension, along with the total peripheral resistance (TPR) decrease and relative hypovolemia. Blood pressures of patients undergoing epidural block were stable or slightly decreased during the establishment of anesthesia. However, in all cases of general anesthesia a variable hypotension was observed during induction and intubation. We therefore recommend epidural block for abdominal pheochromocytoma resection in order to avoid the marked fluctuation of blood pressure which may accompany the induction of general anesthesia.