允许性高碳酸血症在腹腔镜直肠癌手术中的应用及对循环的影响

目的:研究允许性高碳酸血症在腹腔镜直肠癌手术中的应用效果、最佳适宜范围及对患者循环功能的影响。方法:选取沧州市中心医院拟择期行腹腔镜直肠癌手术的患者90例,随机分为试验1组、2组和对照组3组,每组30例。试验1组血二氧化碳分压(partial pressure of carbon dioxide,PaCO_2)维持在56～65 mm Hg,试验2组PaCO_2维持在46～55 mm Hg,对照组PaCO_2维持在35～45 mm Hg。观察并比较三组患者气腹时间、机械通气时间、手术时间、拔管时间、苏醒时间,气腹前10 min(T_1)、气腹后1 h(T_2)、气腹后2 h(T_3)、放气后15 min(T_4)时间点的平均动脉压、心率、气道峰压,计算动态肺顺应性、氧合指数,记录皮下气肿、呕吐、烦躁及术后认知功能障碍等并发症的发生情况。结果:三组患者手术时间、气腹时间、机械通气时间、拔管时间和苏醒时间比较差异无统计学意义(P0.05)。与对照组相比,试验组T_2、T_3时心率(heart rate,HR)、血氧分压(partial pressure of oxygen,PaO_2)、肺动态顺应性(lung dynamic compliance,Cdyn)均明显升高,P_(max)明显下降(P0.05);与T_1相比,试验组T_2、T_3时HR、气道峰压(Pmax)、PaO_2均升高,Cdyn下降(P0.05);与试验2组比较,试验1组HR、P_(max)明显更低,PaO_2、Cdyn明显更高(P0.05),但三组氧合指数(oxy-genation Index,OI)比较差异无统计学意义(P0.05)。与对照组相比,试验组T_2、T_3时动脉血二氧化碳分压(partial pressure of car-bon dioxide,PaCO_2)、Qs/Qt均升高,氢离子浓度指数(hydrogen ion concentration,pH)、平均动脉压(mean arterial pressure,MAP)下降;与T_1相比,试验组T_2、T_3时PaCO_2、Qs/Qt均升高,pH、MAP下降;与试验2组比较,试验1组PaCO_2、PaCO_2明显更低,pH明显更高(P0.05),但三组MAP比较差异无统计学意义(P0.05)。手术开始30 min和1 h,试验组中心静脉压(central venous pressure,CVP)、心输出量(cardiac output,CO)以及心脏指数(cardiac index,CI)较对照组更低,而试验1组较试验2组明显更低(P0.05)。三组并发症的改善情况比较差异无统计学意义(x~2=0.1973,P=0.9954)。治疗后,试验组MMSE评分较治疗前明显降低,且试验组明显高于对照组,而试验1组又显著高于试验2组(P0.05)。结论:允许性高碳酸血症在长时间腹腔镜直肠癌手术中在保障氧合同时降低气道压改善肺的顺应性,可一定程度上减少术后认知功能障碍的发生,有一定的脑保护作用。

Applications and Effects allow Hypercapnia in Laparoscopic Surgery for Colorectal Cancer Circulatory Function

ABSTRACT Objective: To study the effect of permissible hypercapnia in laparoscopic rectal cancer surgery, the optimal range of application and the effect on the patient''s circulatory function. Methods: 90 cases with rectal cancer were researched to undergoing la- paroscopic surgery according to the random number table they were divided into Test 1 group, 2 groups and control group, 30 cases in each group. The PaCO₂ of the test group 1 was maintained at 56-65 mmHg, the PaCO₂ of the test group 2 was maintained at 46-55 mmHg, and the PaCO₂ of the control group was maintained at 35-45 mmHg. They were compared with Pneumoperitoneum time, me- chanical ventilation time, operation time, extubation time, wake-up time, mean arterial pressure, heart rate, and airway pressure at 10 minutes before pneumoperitoneum (T₁), 1 hour after pneumoperitoneum (T₂), 2 h after pneumoperitoneum (T₃), and 15 min after defla- tion (T₄). dynamic lung compliance, oxygenation index, recording of complications such as subcutaneous emphysema, vomiting, irritabil- ity and postoperative cognitive impairment. Results: There was no significant difference in the operation time, pneumoperitoneum time, mechanical ventilation time, extubation time and recovery time between the three groups (P>0.05). Compared with the control group, HR, PaO₂, and Cdyn in the test group significantly increased at T₂ and T₃, and P _max decreased significantly; compared with T₁, HR, P _max , and PaO₂ in the test group increased at T₂ and T₃, and Cdyn decreased; Compared with the experimental group 2, the HR and P _max of the experimental group 1 were significantly lower, PaO₂ and Cdyn were significantly higher, and the difference between the three groups was significant (P<0.05), but there was no significant difference in the OI between the three groups (P>0.05). Compared with the control group, the PaCO₂, Qs/Qt of the test group increased at T₂ and T₃, and the pH and MAP decreased. Compared with T₁, the PaCO₂, Qs/Qt of the test group increased at T₂ and T₃, and the pH and MAP decreased. Compared with the experimental group 2, the Pa- CO₂ and PaCO₂ in the experimental group 1 were significantly lower and the pH was significantly higher(P<0.05), but there was no sig- nificant difference in the MAP between the three groups(P>0.05). There was no significant difference in preoperative CO, CVP, and CI between the three groups(P>0.05). At 30 min and 1 h after surgery, CO, CVP, and CI were lower in the experimental group than in the control group, while the experimental group 1 was significantly more lower than the experimental group 2(P<0.05). There was no signifi- cant difference in the improvement of complications between the three groups(x²=0.1973, P=0.9954); the MMSE score after treatment was significantly lower than before treatment, and the test group was significantly higher than the control group, and the test group 1 was significantly higher than the test 2 group(P<0.05). Conclusion: Permissive hypercapnia protects lung compliance by reducing airway pres- sure during oxygen laparoscopic surgery for prolonged laparoscopic rectal cancer surgery, and can reduce the occurrence of postoperative cognitive impairment to a certain extent, it has a certain degree of brain protection.