全身麻醉对小儿听性脑干反应测试结果的影响

目的 研究应用听性脑干反应(auditory brainstem reaction，ABR)作为监测小儿全身麻醉深度与觉醒的客观指标。方法 选择听力正常的外科择期手术患儿45例，按照美国麻醉学家学会表针分为I～Ⅱ级，分别施行异丙酚静脉麻醉、芬太尼静脉麻醉及异氟醚吸入全身麻醉，随机每组15例，应用丹麦Madsen诱发电位反应仪监测并记录麻醉各阶段ABR的I、Ⅲ、Ⅴ波潜伏期及I-Ⅲ、Ⅲ-Ⅴ、I-Ⅴ波间期，研究观察潜伏期和波间期随时间推移及麻醉剂量变化之间的关系，探讨ABR在异丙酚、芬太尼及异氟醚等不同麻醉中的表现特征和规律。结果 ①异丙酚静脉麻醉和异氟醚吸入麻醉与剂量呈良好的正相关；②I波的潜伏期特性对于控制麻醉深度极为重要；③Ⅴ波监测麻醉具有最佳的稳定性及相关性；④停用麻醉药一段时间或患儿基本清醒时，ABR各波潜伏期和波间期有的仍高于正常值，这是滞后(延迟)反应；⑤ABR对芬太尼术中的觉醒监测不太敏感。结论 ABR各波的潜伏期及波间期变化，可判断小儿全身麻醉深度，在一定程度上可作为判断觉醒的参考，但应考虑有延迟反应的可能。

Clinical study on applying brainstem auditory evoked potential to monitor anesthesia depth and awaken in children]

OBJECTIVES: To study applying auditory brainstem reaction (ABR) to monitor the general anesthesia depth and awaken degree in children as an objective guide. METHODS: Forty-five infant or children patients, American Society of Anesthesiologists(ASA) graded I-II, with normal audition, were selected and divided into 3 groups (15 cases per group) to receive propofal venous anesthesia, fentanyl venous anesthesia, or isoflurane anesthesia, respectively. During anesthesia, peak latencies (PL) of I, III, V wave, and interpeak latencies (IPL) of I-III, III-V, I-V were monitored and recorded after short sound stimulation of 90 db which accumulated 1,000 times with Madsen. The changing of PL and IPL with time passing and anesthesia dosage was studied to discuss the feature of ABR in each anesthesia procedure as above. RESULTS: There is a significant positive correlation between PL and IPL of ABR waves as above and the dosage of propofol or the concentration of isoflurane. The dosage or the concentration increased, and PL and IPL prolonged. It is important of PL of wave I to reflect anesthesia degree. It is wave V with the best stability and correlation to monitor anesthesia degree. After anesthesia period or patients almost awaken, PL and IPL of some ABR waves were still more than normal values, which is detention reaction. For the fentanyl anesthesia, ABR is not sensible enough, i.e. has little correlation. CONCLUSION: The changing of PL and IPL of ABR waves could conclude anesthesia degree in children and be treated as reference of whether awaken or not in some certain, but have possibility of detention reaction.