合并肝肺综合征的老年患者实施胆囊切除术对七氟醚吸入麻醉的药效学研究

The study of sevoflurane pharmacodynamics in elderly patients with hepatopulmonary syndrome during cholecystectomy

目的研究合并肝肺综合征（hepatopulmonary syndrome, HPS ）的老年患者实施胆囊切除术期间吸入七氟醚维持麻醉的药效学变化。方法48例肝硬化择期行胆囊切除术的患者，性别不限，年龄60—74岁，Child-Pugh分级A级或B级，ASA分级Ⅱ或Ⅲ级，肺、肾功能检测正常。利用对比增强超声心动图检查和动脉血气分析，根据是否合并HPS将患者分为HPS组（18例）和对照组（C组，30例）。入室后常规开放静脉通路，泵注右美托咪定镇静。麻醉诱导使用丙泊酚2mg，妇、舒芬太尼2μg／ks和维库溴铵0．1mg／kg，插管后以预设七氟醚浓度维持麻醉，采用上下交叉点法测定MAC值，术中维持BIS值在40—50，保持BP、HR平稳。记录麻醉时间，观察比较两组患者吸入七氟醚MAC值的差异，术毕停药后患者呼之睁眼时间、BIS值恢复至85的时间以及拔管时间。结果HPS组的MAC值为（0．88±0．07）％，而c组的MAC值为（1．13±0．09）％，两组比较，差异有统计学意义（P〈0．05）。与C组比较，HPS组患者术毕停药后呼之睁眼时间[（28±9）min比（16±6）min]、BIS值恢复至85的时间[（34±9）min比（21±7）min]以及拔管时间[（38±5）min比（26±3）min]延迟，差异有统计学意义（P〈0．05）。结论合并HPS老年患者实施胆囊切除术期间使用七氟醚吸入麻醉维持，七氟醚的MAC值显著降低，麻醉维持后苏醒时间明显延迟。

Objective To investigate the change of sevoflurane pharmacodynamics during cholecystectomy in elderly patients with hepatopulmonary syndrome（HPS）. Methods Forty eight cases of patients undergoing elective cholecystectomy, male or female, aged 60 to 74 years old, Child-Pugh class A or B grade, ASA grade Ⅲ or Ⅱ, with normal function of lung and renal, were chosen for this study. These patients were divided into hepatopulmonary syndrome group （group HPS, n=18） and normal group （group C, n=30） according to the result of contrast-enhanced echocardiography and arterial blood gas analysis. All patients were established venous channels and sedated with dexmedetomidine after entering the operation room. Anesthesia was induced with propofol 2 mg/kg, sufentanil 2 p^g/kg and vecuronium 0.l mg/kg. After intubation, concentration of sevoflurane is maintained at a preset level to maintain anesthesia. MAC value was measured by upper and lower cross-point assay. During operation, BIS value was maintained within 40-50, blood pressure and heart rate were maintained stable. Duration of anesthesia was record. We observed the difference of sevoflurane MAC values between two groups, time of opening eyes after surgery, as well as time of BIS values recovered to 85. Results MAC of group HPS（0.88±0.07）%, while the MAC of group C（1.13±0.9）%, the two groups were significantly different（P〈0.05）. Compared with group C, patients in group HPS demonstrated increased time to open eyes after withdrawl [（28±9） min vs （16±6） rain], BIS values recovered to 85 [（34±9） rain vs （21±7） mini and extubation [（38±5） rain vs （26±3） min]（P〈0.05）. Conclusions The requirement of sevoflurane decrease in elderly patients with HPS during cholecystectomy and recovery time delay significantly.