Roger Whittaker1, Allan Scott, Morag Gardner. 1. School of Neurology, Neurobiology and Psychiatry, University of Newcastle upon Tyne, Newcastle upon Tyne, UK, and Electroconvulsive Therapy Clinic, Royal Edinburgh Hospital, Edinburgh, Scotland.
Abstract
BACKGROUND: It has been suggested that prolonged cerebral seizures are more prevalent in contemporary practice than realized partly because they may go undetected in the absence of monitoring by electroencephalogram (EEG). The previous report on this topic from Scotland concerned only patients taking part in research and may not be generalizable to routine clinical practice; moreover, the EEG monitoring was not all carried out at a standardized point in the course of treatment. OBJECTIVE: We sought to establish the prevalence of prolonged cerebral seizures in a representative sample from routine clinical practice in Edinburgh and do so at the first treatment, when the risk is greatest. METHOD: Two-channel EEG monitoring was conducted at the first treatment in a new course given to 100 individual consecutive patients. RESULTS: The titration had to be curtailed for anesthetic reasons in 2 patients, and no cerebral seizure was induced. Electroencephalogram measurement of seizure duration was practicable in only 95 of the remaining patients. Two cerebral seizures longer than 120 seconds were detected. One seizure ended spontaneously after 158 seconds and was associated with a generalized convulsion lasting 77 seconds. One was medically terminated after 180 seconds and was associated with a generalized convulsion lasting 122 seconds; this patient had an encephalopathy during the index illness. CONCLUSIONS: The prevalence of prolonged seizures in our routine clinical practice was 1% to 2%, depending on the definition of prolonged cerebral seizure activity.
BACKGROUND: It has been suggested that prolonged cerebral seizures are more prevalent in contemporary practice than realized partly because they may go undetected in the absence of monitoring by electroencephalogram (EEG). The previous report on this topic from Scotland concerned only patients taking part in research and may not be generalizable to routine clinical practice; moreover, the EEG monitoring was not all carried out at a standardized point in the course of treatment. OBJECTIVE: We sought to establish the prevalence of prolonged cerebral seizures in a representative sample from routine clinical practice in Edinburgh and do so at the first treatment, when the risk is greatest. METHOD: Two-channel EEG monitoring was conducted at the first treatment in a new course given to 100 individual consecutive patients. RESULTS: The titration had to be curtailed for anesthetic reasons in 2 patients, and no cerebral seizure was induced. Electroencephalogram measurement of seizure duration was practicable in only 95 of the remaining patients. Two cerebral seizures longer than 120 seconds were detected. One seizure ended spontaneously after 158 seconds and was associated with a generalized convulsion lasting 77 seconds. One was medically terminated after 180 seconds and was associated with a generalized convulsion lasting 122 seconds; this patient had an encephalopathy during the index illness. CONCLUSIONS: The prevalence of prolonged seizures in our routine clinical practice was 1% to 2%, depending on the definition of prolonged cerebral seizure activity.