术中调控不同呼气末二氧化碳分压对老年腹腔镜手术患者术后认知功能的影响

Effects of different P_(ET)CO_2 modulating during operation on postoperative cognitive function in elderly patients undergoing laparoscopic surgery

目的探讨术中维持不同的PETCO2值对老年腹腔镜手术患者术后认知功能的影响。方法择期全麻下行腹腔镜胆囊切除术和腹腔镜胆囊切除胆总管切开取石“T”管引流术的患者50例，年龄65～75岁，体重45～70kg，随机均分为两组，L组，术中通过调控呼吸参数维持气腹后PETCO2在35-39mmHg；H组，维持PETCO2在40～45mmHg，每组25例。记录气腹前5min（T0）、气腹后5min（T1）、15min（T2）、30min（T3）的PETC02及VT、RR、气道峰压（Ppeak），同时于T0～T3时分别采集桡动脉血及颈内静脉球部血行血气分析，计算动一静脉血氧含量差（Da-jv02）和脑氧摄取率（CERO2）。于术前1d及术后3d行简易智力状态检测（MMSE）、数字广度（顺、逆）、数字符号、循迹连线、词汇流畅性和单词辨认测试。结果与T0时比较，T1～T3时两组Ppeak明显升高，Da-jvO2、CERO2明显降低；T1～T3时L组VT、RR明显增快，T2、T3时PETCO2、PaCO2明显升高；T2、T3时H组RR明显增快，T1～T3时PETCO2、PaCO2明显升高（P〈0．05）。与H组比较，L组T2～T3时VT明显升高RR明显增快，T2、T3时Ppeak明显升高，T1～T3时PETCO2、PaCO2明显降低，T3时Da-jvO2、CERO2明显升高（P〉0．05）。与H组比较，L组术后3d单词辨认明显降低（P〈0．05）。与术前1d比较，术后3d两组MMSE、数字广度（逆）、数字符号、明显降低循迹连线明显升高，L组数字广度（顺）、词汇流畅性单词辨认明显降低（P〈0．05）。结论术中调控PETCO2在40～45mmHg可减轻老年患者腹腔镜术后短时字词记忆能力损害，改善POCD，且术中呼吸参数调整较平稳。

Objective To observe the effects of different PETCO2 during operation on post- operative cognitive function in elderly patients undergoing laparoscopic surgery. Methods Fifty elderly patients （65-75 years old, weight 45-70 kg） scheduled for laparoscopic cholecystectomy and laparoseopic cholecystectomy choledocholithotomy with ＂T＂tube drainage were randomly divided into two group, group L（n=25） control PETCO2 in the range of 35-39 mm Hg during operation through the modulating of respiratory parameters after pneumoperitoneum, group H （n= 25）control of PEr CO2 in the range of 40-45 mm Hg. PETCO2, VT, RR, airway pressure （Ppeak） were recorded at 5 min before pneumoperitoneum （T0）, 5 min （T1）, 15 min （T2）, 30 min （T3） after pneumoperitoneum, blood samples were taken from the radial artery and jugular vein for blood gas analyses atT0-T3 at the same time for counting cerebral A-V O2 content differences （Da-jvO2） and cerebral 02 extraction rate （CERO2）. Mini mental state examination （MMSE）, digit span （CIS, inverse）, digit symbol, trail connection, verbal fluency and word recognition test were assessed at 1 d before operation, and 3 d after operation. Results Compared with To, Ppeak was increased, Da-jvO2 and CERO2 were decreased at T1-T3 in both groups; VT and RR were increased at T1-T3, PETCO2 and PaCO2 were increased at T2 ,T3in group L; RR was increased at T2 ,T3, PETCO2 and PaCO2 were increased at T1- T3 in group H（P〈0. 05）. Compared with group H, VTand RR were increased at T1-T3, Ppeak was increase at T2 ,T3, Da-jvO2 and CERO2 was increased at T3, PETCO2 and PaCO2 were decreased at T1-T3. In group L, the number of word recognition was decreased 3 d after operation（P〈0.05）. Compared with 1 d before operation, two groups of MMSE （inverse）, digit span, digit symbol were decreased, trail connection increased, the digit span （CIS）, verbal fluency,word recognition in group L also decreased （P〈0.05）. Conclusion Controling of P〈rCO2 in the range of 40-45 mm Hg during laparoscopic operation can seduce the short-term word memory impairment and improve POCD in elderly patients after surgery, and makes respiratory parameters adjustment more stable.