To determine the safety of apnea testing.
Prospective, consecutive study.
Inner-city trauma center.
A total of 70 apnea tests were performed on 61 comatose patients as part of the determination of brain death.
Only 43 examinations (61%) were well tolerated. During 27 examinations (39%) patients either developed marked hypotension (≥ 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), seven were successfully completed after increases in the rate of dopamine infusion during the test.
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.