Nonconvulsive Status Epilepticus After Electroconvulsive Therapy: A Review of Literature.

BACKGROUND: The clinical presentation and risk factors of nonconvulsive status epilepticus (NCSE) in the context of electroconvulsive therapy (ECT) are poorly understood, and guidance regarding diagnosis and management remains scarce. In this article, we identify case reports of ECT-induced NCSE from literature, and discuss the presentation, diagnosis, and management of these cases in the context of what is known about NCSE from the neurology literature.

METHODS: A literature search on PubMed for case reports of NCSE after ECT.

RESULTS: We identified 13 cases for this review. Diagnosis in all cases was based on clinical features and electroencephalogram (EEG) findings. Clinical presentation was altered mental status or unresponsiveness, with subtle motor phenomena in some cases. All cases had nonspecific risk factors that have been associated with prolonged seizures and convulsions, such as recent discontinuation/reduction of benzodiazepines or anticonvulsants, and concurrent use of antipsychotics and antidepressants. All patients were treated with either benzodiazepines or antiepileptic agents. Outcomes in these post-ECT NCSE cases were generally favorable.

DISCUSSION: Although rare, post-ECT NCSE should be kept in mind by physicians when confusion or unresponsiveness develops and continues after ECT; multilead EEG is gold standard for diagnosis. An intravenous (IV) antiepileptic drug (AED) challenge can help clarify the diagnosis. Initial treatment is recommended with IV benzodiazepines, with a repeat dose if necessary. If seizures persist, IV AEDs are warranted. NCSE refractory to this treatment should be treated with a scheduled IV or oral AED. Serial multilead EEGs should be used to monitor resolution of symptoms.

CONCLUSION: NCSE after ECT is a rare but recognizable clinical event. A high clinical suspicion and low threshold for EEG is necessary for prompt diagnosis.