Transient drug-induced abolition of BAEPs in coma.

Combined infusion of high doses of lidocaine and thiopental in a comatose patient induced major latency and amplitude BAEP changes, which progressed to complete BAEP abolition. Responses returned to normal after drugs were discontinued. EEGs during the episodes showed long-lasting periods of activity suppression, but were never isoelectric. BAEPs are resistant to hypothermia and barbiturates, but must be interpreted cautiously in patients treated with a combination of anesthetic drugs that includes lidocaine.