Brain stem death is a confirmation of death based upon a set of criteria that, in general, tests the brain stem reflexes. It is thought that if the brain stem does not respond to these reflexes during the examination, the brain and body are no longer able to communicate and, therefore, the patient does not have a chance at recovery. As such, the patient is then declared dead. The examination for brain stem death is not a light one, as the patient has to pass strict preconditions before being considered for the test. If the patient does pass, the procedure has to be performed by two senior doctors, and the patient has to show no brain stem reflexes on two separate occasions; that is, he must pass the test twice.
There are three stages in a brain stem death diagnosis. First, the cause of the patient’s coma must be known and the doctor must also establish that the patient suffers from brain damage that is beyond repair. Second, the patient must not be in a condition in which his brain stem dysfunction is reversible and, thus, might alter the results of the examination. For instance, medications, hypothermia and severe metabolic upset can cause the patient to not respond to brain stem stimulation. Third, the patient can’t exhibit brain stem reflexes at all in response to the criteria set forth in the examination.
The examination will take less than half an hour long to perform, less time than it would take to prepare the patient for the test. As the doctors perform the test, they will look for signs of responses that the brain stem would normally communicate in reaction to stimulation. All of these criteria must be satisfied for a confirmation of brain stem death.
The first criteria is that the patient’s pupils do not constrict in response to direct light that is shined into the eyes. Second, the patient’s eyes do not blink in response to cornea stimulation, such as when the doctor strokes the cornea with a piece of cloth or tissue. Third, the patient does not respond, such as grimace, when the doctor applies firm pressure, for example, right above the eye socket. Fourth, the patient’s eyes do not move, as they normally would, in response to ice water being flushed into the ear. Fifth, the patient does not cough or gag when the doctor stimulates the back of the throat or passes a breathing tube down the airway; last, the patient does not breathe on his own when he is detached from the ventilator.