呼气末二氧化碳分压对腹腔镜直肠癌根治术老年患者术后认知功能影响

Effect of end-tidal carbon dioxide partial pressure on postoperative cognitive function in elderly patients undergoing laparoscopic radical rectectomy

目的观察呼气末二氧化碳分压(P_(ET)CO_2)对腹腔镜直肠癌根治术老年患者术后认知功能影响。方法例84行腹腔镜直肠癌根治术老年患者随机分为A、B组,P_(ET)CO_2分别维持在40~45 mm Hg和35~39 mm Hg。检测血清S100β蛋白浓度、潮气量(V_T)、气道峰压(Ppeak)、动脉二氧化碳分压(PaCO_2)、动-静脉血氧含量差、脑氧摄取率,用简易精神状态量表(MMSE)评估术后认知功能障碍(POCD)。结果 A组POCD发生率及术后6、24 h、72 h血清S100β蛋白浓度明显低于B组(P<0.01)。气腹后30、60 min,A组V_T、Ppeak、动-静脉血氧含量差和脑氧摄取率均低于B组,而PaCO_2高于B组(P<0.05)。结论40~45 mm Hg P_(ET)CO_2可减轻神经系统损伤,维持呼吸参数平稳,降低POCD发生率。

Objective To observe the effect of end-tidal CO2 partial pressure （PETCO2） on postoperative cognitive function in elderly patients undergoing laparoscopic radical rectectomy（LRR）. Methods Eighty-four elderly patients with LRR were randomized to A group （PETCO2=40-45 mmHg） and B （PETCO2=35-39 mmHg） groups. Serum S 10013 protein level, tidal volume （VT）, peak airway pressure （Ppeak）, arterial partial pressure of CO2 （PaCO2）, arteriovenous oxygen content difference, and cerebral oxygen extraction rate were detected, and postoperative cognitive dysfunction （POCD） was evaluated by mini-mental state examination （MMSE）. Results The incidence of POCD, and serum level of S1001β protein 6 h and 24 h postoperation were lower in A group than B group （P〈0.01）. At 30 min and 60 min after pneumoperitoneum, VT, Ppeak, arteriovenous oxygen content difference and cerebral oxygen extraction rate were decreased but PaCO2 increased in A group compared with B group （P〈0.05）. Conclusion PETCO2 of 40-45 mmHg can alleviate nervous system injury, maintain respiratory parameters, and reduce POCD incidence.