允许性高碳酸血症对腹腔镜肝部分切除术患者脑氧饱和度的影响

Impact of permissive hypercapnia on cerebral oxygen saturation in patients undergoing laparoscopic partial hepatectomy

摘要:

目的 探讨允许性高碳酸血症（PHC）对控制性低中心静脉压腹腔镜肝部分切除术患者脑氧饱和度的影响。方法 选取2023年1月—2024年8月中南大学湘雅医学院附属株洲医院70例择期行腹腔镜肝部分切除术的患者，按照随机数字表法将患者分为动脉血二氧化碳分压（PaCO₂）正常范围组和PHC组，各35例。气管插管后行机械通气，PaCO₂正常范围组维持PaCO₂在35～45 mmHg，PHC组维持PaCO₂在50～60 mmHg。术中实施控制性低中心静脉压技术，切肝结束前维持中心静脉压（CVP）< 5 cmH₂O。比较两组患者麻醉前（T₀）、气腹前即刻（T₁）、反Trendelenburg体位后5 min（T₂）、第一肝门阻断后5 min（T₃）、切肝结束后5 min（T₄）和术毕（T₅）时的脑氧饱和度（rSO₂）、脑电双频指数（BIS）、血气分析指标及血流动力学指标［呼气末二氧化碳（P_ETCO₂）、中心静脉压（CVP）、平均动脉压（MAP）、心率（HR）及血氧饱和度（SpO₂）］变化情况；比较两组患者术前1 d、术后3 d和术后7 d采用简易智能精神状态检查量表（MMSE）认知功能评分差异；比较两组患者手术时间、术中出血量、总断肝时间、拔管时间、住院时间及并发症发生情况。结果 PHC组拔管时间、住院时间均短于PaCO₂正常范围组（P <0.05）。两组患者T₀～T₅时间点血流动力学指标比较，结果 ①不同时间点的CVP、MAP、HR、SpO₂、P_ETCO₂、rSO₂、BIS比较，差异均有统计学意义（P <0.05）；②两组患者P_ETCO₂、rSO₂比较，差异均有统计学意义（P <0.05），；③两组患者P_ETCO₂、rSO₂变化趋势比较，差异有统计学意义（P <0.05）。两组患者T₀～T₅时间点的动脉血气分析相关指标相比较，结果 ①不同时间点的PaCO₂、PaO₂、Lac、Hb比较，差异有统计学意义（P <0.05）；②两组患者PaCO₂比较，差异有统计学意义（P <0.05）；③两组患者PaCO₂变化趋势比较，差异有统计学意义（P <0.05）。，PHC组MMSE评分高于PaCO₂正常范围组（P <0.05）。PHC组与PaCO₂正常范围组术中大出血、恶心呕吐率比较，差异均无统计学意义（P >0.05）。结论 PHC可提高低中心静脉压腹腔镜肝部分切除术患者的脑氧饱和度，改善术后早期认知功能，具有一定的脑保护作用。

Abstract:

Objective To investigate the impact of permissive hypercapnia (PHC) on cerebral oxygen saturation in patients undergoing laparoscopic partial hepatectomy with controlled low central venous pressure (CVP).Methods Seventy cases of patients undergoing selective laparoscopic partial hepatectomy from January 2023 to August 2024 in our hospital were selected and randomly divided into the Group C (normal PaCO₂) and the Group H (permissive hypercapnia), each with 35 cases. After tracheal intubation and mechanical ventilation, PaCO₂ was maintained at 35-45 mmHg in the Group C and 50-60 mmHg in the Group H. Controlled low CVP technique was applied intraoperatively, maintaining CVP below 5 cmH₂O until the completion of liver resection. The regional cerebral oxygen saturation (rSO₂), bispectral index (BIS), blood gas parameters and hemodynamic indices (P_ETCO₂, CVP, MAP, HR and SpO₂) of the two groups were compared before anesthesia (T₀), immediately before pneumoperitoneum (T₁), 5 min after reverse Trendelenburg position (T₂), 5 min after the first hepatic hilum clamping (T₃), 5 min after the end of hepatectomy (T₄) and at the end of surgery (T₅). The Mini-mental State Examination (MMSE) was used to compare the cognitive function between two groups at 1 day before surgery, 3 days after surgery and 7 days after surgery. The operative duration, intraoperative blood loss, total hepatic hilum clamping time, extubation time, length of hospital stays and complications of the two groups were compared.Results Group H exhibited significantly shorter extubation time and length of hospital stays compared to Group C (P < 0.05). The hemodynamic parameters of the two groups were compared at time points T₀-T₅, which demonstrated differences in CVP, MAP, HR, SpO₂, P_ETCO₂, rSO₂, and BIS across the time points (P < 0.05) and differences in PETCO₂ and rSO₂ between the two groups (P < 0.05). The change trends of P_ETCO₂ and rSO₂ between the two groups were also significantly different (P < 0.05). The comparison of arterial blood gas parameters at T₀-T₅ showed that the PaCO?, PaO₂, and Lac and Hb levels were different across the time points (P < 0.05) and that the PaCO₂ differed significantly between the two groups (P < 0.05). The change trend of PaCO₂ was also different between the two groups (P < 0.05). The MMSE score in the Group H was significantly higher than that in the Group C (P < 0.05). No significant differences were found between the two groups in the incidence of intraoperative massive bleeding or postoperative nausea and vomiting (P > 0.05).Conclusion PHC can increase cerebral oxygen saturation in patients undergoing laparoscopic partial hepatectomy with controlled low CVP, improve early postoperative cognitive function, and exert a certain neuroprotective effect.