二氧化碳气腹及头低位对老年患者脑氧供需平衡和能量代谢的影响

摘要

目的 观察腹腔镜直肠癌根治术期间二氧化碳气腹及头低位对老年患者脑氧供需平衡和能量代谢的影响.方法 选择26例行腹腔镜直肠癌根治术的老年患者(年龄＞60岁),美国麻醉医师协会分级Ⅰ～Ⅱ级,无脑血管事件病史,分别于气腹前即刻(T1)、气腹后30 min(T2)、60 min(T3)、90 min(T4)记录桡动脉和颈静脉球血气、血糖、乳酸、颈静脉球部压力(JBP)等,计算脑动静脉氧含量差(Da-jO2)和脑葡萄糖摄取量(Da-jglu).结果 与T1比较,T2、T3和T4时平均动脉压(MAP)、JBP、颈静脉球血氧饱和度(SjvO2)、动脉二氧化碳分压(PaCO2)、脑灌注压(CPP)均显著增加(P＜0.01),Da-jO2均显著减少(P＜0.01),T3和T4时Da-jglu显著减少(P＜0.05),而颈静脉球乳酸含量的差别无统计学意义(P＞0.05).结论 老年患者在气腹头低位期间脑氧供大于氧需,脑循环过度灌注,脑组织对葡萄糖的利用率降低,但能量代谢正常.%Objective To evaluate the effect of carbon dioxide gas pneumoperitoneum in the steep trendelenburg position on the balance between cerebral oxygen supply and demand and metabolism in the aged during laparoscopic radical resection of rectum cancer. Methods Twenty-six patients of American society of anesthesiologist I-II physical status without previous episodes of cerebral ischemia or hemorrhage were performed laparoscopic radical resection of rectum cancer. The values of blood gas of glomus jugulare, blood glucose and lactate of the arterial and jugular bulb blood pressure (JBP) were recorded before insufflation (T,) ,30 minutes (T2) ,60 minutes (T3) ,90 minutes (T4) after the insufflation, respectively. Brain arteriove-nous oxygen content ( Da-Jo2) difference and glucose uptake (Da-jglu) were calculated. Results Compared with those before the insufflation(T, ) ,mean arterial pressure(MAP),JBP,jugular bulb venous saturation(SjvO2) ,arterial partial pressure carbon dioxide(PaCO2) and cerebral perfusion pressure (CPP) increased significantly (P <0.01) ,the Da-Jo2 decreased in T2 ,T3 and T4(P<0.01) ,and the Da-jglu in T3 and T4 decreased significantly(P<0.05) ,but there was no statistically significant in jugular bulb blood lactate(P >0.05). Conclusion During laparoscopic radical resection of rectum cancer, the balance between cerebral oxygen supply and demand,as assessed by SjvO2 ,are disorganized,oxygen supply exceeded oxygen consumption in the aged,which suggests that the procedure induced cerebral hyperperfusion,the cerebral ingestion of glucose is decreased, but without impacting on the brain energy metabolism.