Ochiai Ryoichi, Yamada Tatsuya, Kiyama Shunya, Nakaoji Takako, Takeda Junzo
Department of Anesthesiology, School of Medicine, Keio University, Tokyo, Japan.
Anesth Analg. 2004 Apr;98(4):1030-1035. doi: 10.1213/01.ANE.0000105874.50605.3C.
The prediction of seizure thresholds in electroconvulsive therapy (ECT) remains problematic. We examined the relationship between bispectral index (BIS) score and seizure duration in ECT performed under thiopental anesthesia in patients receiving their usual regimen of antidepressant medication for its potential as a predictor of seizure inducibility. One-hundred ECT treatments were evaluated in 16 adult patients diagnosed with depression. BIS scores were recorded at the preanesthetic and preictal periods and at recovery from ECT. Seizure duration was defined as the duration of the electroencephalogram seizure pattern. The relationships between preanesthetic and preictal BIS scores and seizure duration were evaluated. Effective seizure threshold was determined by receiver operator characteristic analysis, and the area under the curve (AUC) was calculated for seizure durations of more than 10 s, more than 20 s, and more than 30 s. The relationship between seizure duration and thiopental estimated effect-site and plasma concentrations was analyzed as well. Preictal BIS scores for seizures lasting longer than 30 s were significantly higher than those for seizures lasting <30 s. A preictal BIS score of 55 or more represents a strongly determinant condition for achieving seizures that last longer than 30 s (AUC, 0.937; receiver operator characteristic), as well as for briefer seizures that last more than 20 or 10 s (AUC: 0.938 and 0.959, respectively). There was no significant correlation between seizure duration and the estimated thiopental effect-site or plasma concentration. We conclude that during thiopental anesthesia, the minimum threshold for inducing seizures of any duration correlates with a preictal BIS score of 55. This threshold was independent of antidepressant regimen and thiopental dosage. We suggest that the preictal BIS score is useful in predicting the ictogenic threshold in ECT.
We found that the bispectral index (BIS) score serves as an indicator of seizure inducibility in electroconvulsive therapy (ECT) under thiopental anesthesia and that the relationship between BIS score and seizure duration was not linear, suggesting that the pharmacological mechanisms by which thiopental and propofol suppress ECT seizure activity are different.
在电休克治疗（ECT）中，癫痫发作阈值的预测仍然存在问题。我们研究了在硫喷妥钠麻醉下接受常规抗抑郁药物治疗的患者进行ECT时，脑电双频指数（BIS）评分与癫痫发作持续时间之间的关系，以评估其作为癫痫发作诱导预测指标的潜力。对16例诊断为抑郁症的成年患者的100次ECT治疗进行了评估。在麻醉前、发作前以及ECT恢复时记录BIS评分。癫痫发作持续时间定义为脑电图癫痫样放电模式的持续时间。评估了麻醉前和发作前BIS评分与癫痫发作持续时间之间的关系。通过受试者工作特征分析确定有效癫痫发作阈值，并计算癫痫发作持续时间超过10秒、超过20秒和超过30秒时的曲线下面积（AUC）。还分析了癫痫发作持续时间与硫喷妥钠效应室和血浆浓度之间的关系。持续时间超过30秒的癫痫发作的发作前BIS评分显著高于持续时间<30秒的癫痫发作。发作前BIS评分为55或更高代表了实现持续时间超过30秒的癫痫发作的强决定条件（AUC，0.937；受试者工作特征），以及持续时间超过20秒或10秒的较短癫痫发作（AUC分别为0.938和0.959）。癫痫发作持续时间与硫喷妥钠效应室或血浆浓度估计值之间无显著相关性。我们得出结论，在硫喷妥钠麻醉期间，诱导任何持续时间癫痫发作的最低阈值与发作前BIS评分为55相关。该阈值与抗抑郁治疗方案和硫喷妥钠剂量无关。我们建议发作前BIS评分有助于预测ECT中的致痫阈值。
我们发现脑电双频指数（BIS）评分可作为硫喷妥钠麻醉下电休克治疗（ECT）中癫痫发作诱导的指标，且BIS评分与癫痫发作持续时间之间的关系并非线性，这表明硫喷妥钠和丙泊酚抑制ECT癫痫活动的药理机制不同。
