Wellman B J, Loftus C M, Kresowik T F, Todd M, Granner M A
Division of Neurosurgery, The University of Iowa Hospitals and Clinics, Iowa City 52242, USA.
Neurosurgery. 1998 Oct;43(4):769-73; discussion 773-5. doi: 10.1097/00006123-199810000-00022.
This study compared the electroencephalographic (EEG) changes occurring during carotid occlusion in 225 consecutive patients undergoing carotid endarterectomies performed by two surgeons, one using local and the other using general anesthesia.
A retrospective review of patients undergoing carotid endarterectomies for carotid occlusive disease was conducted. EEG changes associated with intraoperative ischemia (decreased amplitude, generalized slowing, and loss of fast activity) resulting in the need for an indwelling arterial shunt were recorded for the two anesthesia groups. To determine the similarities or differences between the two groups, the groups were compared regarding age, risk factors, and indications for surgery.
Significant EEG changes were noted in 6 of 96 patients (6.3%) in the local anesthesia group versus 19 of 121 patients (15.7%) in the general anesthesia group. EEG changes consisted solely of generalized slowing in the local anesthesia group, whereas a more varied spectrum was observed in the general anesthesia group. The two groups were similar regarding age and risk factors. Although the local anesthesia group had more asymptomatic patients, symptomatic patients did not have a greater incidence of EEG changes.
There is a large difference in EEG changes potentially requiring shunt placement in patients undergoing surgery while under local (6.3%) versus general (15.7%) anesthesia. This could not be explained based on age, risk factors, interpretation of EEG findings, or indications between the two groups. We conclude that EEG monitoring may be insensitive and may fail to detect ischemia in patients who are under regional anesthesia. Alternately, the presence of general anesthetics may alter the character of the EEG findings and increase the sensitivity of EEG monitoring to ischemic events.
本研究比较了连续225例接受颈动脉内膜切除术的患者在颈动脉闭塞期间发生的脑电图（EEG）变化，这些手术由两位外科医生进行，一位使用局部麻醉，另一位使用全身麻醉。
对因颈动脉闭塞性疾病接受颈动脉内膜切除术的患者进行回顾性研究。记录两个麻醉组中与术中缺血相关的EEG变化（波幅降低、广泛性减慢和快波活动丧失），这些变化导致需要留置动脉分流管。为了确定两组之间的异同，比较了两组患者的年龄、危险因素和手术指征。
局部麻醉组96例患者中有6例（6.3%）出现明显的EEG变化，而全身麻醉组121例患者中有19例（15.7%）出现明显变化。局部麻醉组的EEG变化仅包括广泛性减慢，而全身麻醉组观察到的变化范围更广。两组在年龄和危险因素方面相似。虽然局部麻醉组无症状患者较多，但有症状患者的EEG变化发生率并未更高。
在接受局部麻醉（6.3%）与全身麻醉（15.7%）的手术患者中，潜在需要放置分流管的EEG变化存在很大差异。这无法根据年龄、危险因素、EEG结果的解读或两组之间的手术指征来解释。我们得出结论，EEG监测可能不敏感，可能无法检测到区域麻醉患者的缺血情况。或者，全身麻醉药的存在可能会改变EEG结果的特征，并提高EEG监测对缺血事件的敏感性。
