Pheochromocytoma presenting as shock.

539 cases of pheochromocytoma were reviewed with specific attention to those cases presenting with shock at initial evaluation. Eleven such cases were discovered, for an incidence of 2%. A 12th such case is reported here. The literature is discussed with consideration for diagnosis and management of the patient in unexplained shock, suggesting that such patients may be experiencing cardiovascular collapse secondary to massive catecholamine release from a previously undiagnosed pheochromocytoma. Therapeutic considerations are also discussed.