Comparison of Seizure Duration, Ictal EEG, and Cognitive Effects of Ketamine and Methohexital Anesthesia With ECT

The authors retrospectively compared the seizure duration, ictal EEG, and cognitive side effects of ketamine and methohexital anesthesia with ECT. This comparison was carried out with data from consecutive index ECT treatments that occurred immediately before and after a switch from methohexital to ketamine in 36 patients. Ketamine was well tolerated and prolonged seizure duration overall, but particularly in those who had a seizure duration shorter than 25 seconds with methohexital at the maximum available stimulus intensity. Ketamine also increased midictal EEG slow-wave amplitude. Thus, a switch to ketamine may be useful when it is difficult to elicit a robust seizure. Faster post-treatment reorientation with ketamine may suggest a lower level of associated cognitive side effects.