Hsieh J C, Shih Y S, Hwang L D, Lui P K, Lui P W, Lee T Y, Yao C S, Su M S, Chung K P
Department of Anesthesiology, Veterans General Hospital, Taipei.
Ma Zui Xue Za Zhi. 1990 Jun;28(2):127-35.
Epileptic surgery is a radical and ablative treatment for medically refractory epilepsy. Electrocorticoencephalography (ECoG) obtained by subdural strip electrodes should always be used during operation for precise localization of epileptic focus and mapping the extent of its involvement. But difficulties and ambiguities exist when the patient's ECoG is suppressed, either owing to the anticonvulsant used, being at the stage of posterictal period, or the effects of anesthetics during operation. Then, intentional activation of epileptogenic activity should be performed to locate the pathological focus in order to accomplish a successful surgical treatment. Etomidate has been considered as an abnormal electroencephalogram (EEG) activator and its use is not recommended in patients with epilepsy. But lesser dose of etomidate as an activator for ECoG has not been investigated. The study reported here established that etomidate as an hypnotic has not only anesthetic properties but, paradoxically, also activates epileptogenic activity. With the latter pharmacologic characteristic, etomidate can be used to deliberately activate the spikes of the potentially epileptogenic tissue, the delineation and localization of which may help the surgeon determine to what extent the pathological cortex be resected in surgical treatment of a refractory epilepsy. The current recommended dosage of etomidate at veterans General Hospital-Taipei for ECoG in epileptic surgery is 0.1-0.15 mg/kg/iv.
癫痫手术是一种针对药物难治性癫痫的根治性和切除性治疗方法。在手术过程中，应始终使用通过硬膜下条形电极获得的皮质脑电图（ECoG），以精确确定癫痫病灶的位置并描绘其累及范围。但是，当患者的ECoG受到抑制时，就会出现困难和模糊性，这可能是由于使用了抗惊厥药物、处于发作后期阶段或手术期间麻醉剂的作用。然后，应进行癫痫源性活动的有意激活以定位病理病灶，从而完成成功的手术治疗。依托咪酯被认为是一种异常脑电图（EEG）激活剂，不建议在癫痫患者中使用。但是，尚未研究较小剂量的依托咪酯作为ECoG激活剂的情况。本文报道的研究表明，依托咪酯作为一种催眠药，不仅具有麻醉特性，而且自相矛盾的是，还能激活癫痫源性活动。凭借后一种药理特性，依托咪酯可用于故意激活潜在癫痫源组织的棘波，其描绘和定位可能有助于外科医生确定在难治性癫痫的手术治疗中应切除病理皮层的程度。台北荣民总医院目前推荐的癫痫手术中用于ECoG的依托咪酯剂量为0.1-0.15mg/kg静脉注射。
