Duration of Electroconvulsive Therapy Postictal Burst Suppression Is Associated With Time to Reorientation

A burst suppression pattern in the electroencephalogram represents a down-regulated brain state, which also occurs in the postictal phase of electroconvulsive therapy (ECT). Suppressive actions of the brain to terminate the seizure are thought to be necessary for the efficacy of ECT. On the other hand, recent studies showed an association of burst suppression in general anesthesia or sedation with (postprocedural) cognitive complications.

We retrospectively examined the length of postictal burst suppression and reorientation time in 49 ECT sessions of 25 consecutive patients. Burst suppression duration was determined by bispectral index monitoring and defined as the time with a bispectral index value of less than 20%. The association between duration of burst suppression and reorientation time was analyzed with multivariate logistic and linear regression analysis controlling for several covariates.

The reorientation time showed a statistically significant association with the duration of burst suppression, but with no other variable. Longer phase of postictal burst suppression predicted longer reorientation time in the recovery room (P = 0.046).

The association between the duration of postictal burst suppression and reorientation time after ECT in this sample suggests that (not only the efficacy but also the) cognitive adverse effects of ECT might be related to the extent of postictal central inhibition after the termination of the seizure.