Increased Stimulation Intensity Helped to Cope with Prolonged Seizures During the Next Round of Modified Electroconvulsive Therapy: A Case Report

BACKGROUND: Numerous protocols exist to counteract prolonged seizures during modified electroconvulsive therapy (mECT), such as anaesthetic adjustments and ventilation. Evidence on methods for deciding whether to continue with the next round of mECT after a prolonged seizure and to prevent recurrent seizures is currently not well established. CASE PRESENTATION: The patient was a 76-year-old woman with major depressive disorder. She suffered from depressive symptoms such as decreased appetite, anxiety, and agitation. She was admitted to our hospital for mECT for the fifth time. The mECT was bilateral and started at 35% stimulus intensity, and effective convulsions were obtained for the first time. During the 8th mECT at the same intensity (35% stimulus intensity), an unexpected prolonged seizure of 966 s (over 16 minutes) occurred. The seizure was abruptly stopped with diazepam 10 mg and midazolam 2 mg. During the ninth mECT session, the stimulation intensity was increased to 50%, which resulted in effective seizures and no prolonged seizures. Subsequently, appropriate convulsions were obtained with the same stimulation intensity, and she completed 12 sessions. Her depressive symptoms improved, and she was discharged on the 45th day of hospitalization. CONCLUSION: Prolonged seizures in mECT can be prevented by raising the stimulation intensity during the following cycle.