OBJECTIVE: To determine the safety of apnea testing. DESIGN: Prospective, consecutive study. SETTING: Inner-city trauma center. PATIENTS: A total of 70 apnea tests were performed on 61 comatose patients as part of the determination of brain death. RESULTS: Only 43 examinations (61%) were well tolerated. During 27 examinations (39%) patients either developed marked hypotension (> or = 15% drop in mean arterial pressure) (n = 23) or required prophylactic vasopressor manipulation (n = 4). Of the 27 examinations in which hypotension developed, 14 were aborted, two were tolerated despite marked hypotension, four were tolerated after administration of prophylactic epinephrine (n = 1) or dopamine hydrochloride (n = 3), and seven were successfully completed after increases in the rate of dopamine infusion during the test. CONCLUSIONS: Hypotension can pose a significant risk to patients undergoing apnea testing. Constant monitoring of vital signs throughout the test is essential to its safe completion.
