No surgeon wants a patient to wake up deaf, blind, paralyzed, or generally brain-damaged, and evoked potential (EP) monitoring during certain forms of surgery may afford an ounce of prevention.
"There is a compelling need to monitor the central nervous system with the same degree of reliability as the heart," said Peter Raudzens, MD, of the Barrow Neurological Institute, St Joseph's Medical Center, Phoenix, Ariz, at the recent New York conference on EPs.
Raudzens, who has measured EPs in more than 170 patients, has found that early brainstem auditory EPs (BAEPs), in particular, give good indexes of developing auditory dysfunction while the neurosurgeon still has time to alter what he is doing. "There is about a 10% to 25% incidence of intraoperative change in the auditory system that relates to postoperative hearing problems," he says. These problems have been both temporary and permanent, he noted, although he has followed up