七氟烷用于癫痫手术麻醉及其对脑电图的影响

目的比较不同呼气末含量七氟烷对开颅手术癫痫及非癫痫患者皮层脑电图的影响。以探讨七氟烷是否适合癫痫手术过程中麻醉的维持，并且确定其最佳麻醉维持剂量。方法24例癫痫患者和15例非癫痫需要开颅手术患者常规麻醉后，切开硬膜后置入皮层电极，分别控制呼气末七氟烷含量0．7，1．0，1．3，1．5MAC，稳定15min后记录皮层脑电图，记录并分析棘波和其它脑波变化。结果癫痫组患者在1．0，1．3MAC七氟烷含量时，棘波数量和导联数与0．7MAC时无明显变化，而1．5MAC棘波频数和导联数明显高于0．7MAC时（P〈0．05）。非癫痫组患者在0．7，1．0，1．3MAC时均无棘波出现，在1．5MAC部分病例出现棘波，且导联弥散。随着七氟烷含量的增加，患者其它脑电波形变化相似，α和β波频率减少，δ波频率增加，而θ波频率变化不明显。结论癫痫患者手术时，如果进行皮层脑电监测，七氟烷含量控制在低于1．3MAC为宜。如果术中脑电监测时，无论是否癫痫患者，七氟烷含量大于1．5MAC均可能影响监测结果。

Effect of sevoflurane on electrocorticogram activity for patients with epilepsy in operation

Objective To assess the effects of concentration of sevoflurane on the electrocorticogram (ECoG) of intractable epileptic patients or non-epileptic patients undergoing surgery and investigate the suitable concentration of sevoflurane for epilepsy surgery. Methods Of 24 patients with intractable epilepsy and 15 patients with non-epilepsy but brain diseases, ECoG were recorded under sevoflurane anesthesia with 0.7 minimum alveolar anesthetic concentration (MAC), 1.0 MAC, 1.3 MAC, and 1.5 MAC, respectively, under similar ventilatory conditions. Spike activity and other frequency brain waves were evaluated. Results The frequencies and leads of spike waves (or spike-form waves) were similar with 0.7-1.3 MAC sevoflurane anesthesia in epileptic patients, whereas the spike waves were significantly increased at 1.5 MAC in epileptic patients and 5 of 15 non-epileptic patients (P<0.05). The change of other frequencies brain waves was similar in both group: the frequency of α and β waves decreased, δ waves increased and θ waves changed a little. Conclusion The maintenance of anesthesia with 0.7-1.3 MAC sevoflurane is safe and suitable for the craniotomy surgery of epileptic patients with ECoG monitoring. Careful attention should be paid to the higher concentration of sevoflurane (>1.5 MAC) used when intraperative ECoG is used in both epileptic patients and non-epilepsy patients.