Anesthetic Management of Pheochromocytoma and Paraganglioma

Abstract

Pheochromocytoma and paraganglioma are rare endocrine tumors that pose significant challenge to anesthesiologists. Increased sympathetic activation during induction of anesthesia, tracheal intubation, and surgical incision, and surges of catecholamine release during manipulation of the tumor can precipitate severe hemodynamic instability. Intraoperative complications include malignant hypertension, arrhythmia, myocardial infarction, acute cardiac decompensation, pulmonary edema, and stroke. Careful preoperative preparation with α- and β-blockers and oral intravascular fluid expansion have been shown to decrease the incidence and severity of perioperative hemodynamic instability. Preoperative tests should include 24-h urine catecholamine levels and cardiac evaluation with an electrocardiogram and an echocardiogram. In addition to standard intraoperative monitors, all patients should have an arterial line placed prior to induction of anesthesia. Most patients receive general anesthesia for these surgeries. During the induction of anesthesia, a deep plain of anesthesia and paralysis should be achieved prior to tracheal intubation, to avoid excessive sympathetic stimulation. Potent arterial and venous vasodilators should be readily available to treat hypertensive crises during anesthesia. Arrhythmias should be treated promptly with β-blockers and antiarrhythmic agents. Vasopressors are usually needed to treat hypotension after tumor resection. All vasodilators and vasopressors should be infused via central venous access. Maintenance of general anesthesia is achieved with a volatile anesthetic, with the careful titration of narcotics. The goal of fluid management is to achieve euvolemia. Fluid management should be guided by dynamic parameters of fluid responsiveness. All patients should be recovered in an intensive care unit. Elderly patients are at higher risk for postoperative complications and prolonged hypotension after tumor resection. Care of pheochromocytoma in pregnancy requires a multidisciplinary approach with an endocrinologist, obstetrician, surgeon, and anesthesiologist to best prepare for the timing of surgical resection.