PEEP阶梯改变方向对Trendelenburg体位腔镜手术病人个体化PEEP确定及肺部并发症的影响

Effect of changing direction of PEEP ladder on individualized PEEP determination and pulmonary complications in patients undergoing endoscopic surgery with Trendelenburg position

目的:比较呼气末正压(PEEP)阶梯改变方向及改变过程中每个PEEP水平持续时间的不同对Trendelenburg体位腔镜手术中病人个体化PEEP的确定及肺部动态顺应性和氧合情况的影响。方法:选取择期全麻下行腔镜下结直肠手术病人60例,根据术中PEEP改变方向的不同随机分为递增组和递减组,各30例。递增组病人PEEP从0 cmH_(2)O开始递增至16 cmH_(2)O,递减组由16 cmH_(2)O开始递减至0 cmH_(2)O,所有病人PEEP变化梯度均为2 cmH_(2)O。记录PEEP变化过程中每个PEEP水平下1 min和2 min时麻醉机所显示呼气末的动态肺顺应性(Cdyn),将Cdyn最大时的PEEP定为该方法所获取的个体化PEEP。在PEEP改变过程中,若有创平均动脉压下降>10%基础水平,则给予去氧肾上腺素以维持血流动力学稳定。结果:2组在维持血流动力学稳定过程中需要给予去氧肾上腺素的病人数差异无统计学意义(P>0.05)。2组病人PEEP阶梯前后PaO_(2)/FiO_(2)差异均无统计学意义(P>0.05);递增组病人PEEP阶梯前后PaO_(2)/FiO_(2)差异无统计学意义(P>0.05),递减组病人PEEP阶梯后PaO_(2)/FiO_(2)高于阶梯前(P<0.05)。2组PEEP维持1 min和维持2 min所获取的个体化PEEP差异均无统计学意义(P>0.05)。在PEEP维持时间为1 min,其水平为12、14和16 cmH_(2)O时,以及维持时间为2 min,PEEP水平为8、10、12和14 cm H_(2)O时,递减组Cdyn均明显高于递增组(P<0.01)。结论:在病人接受Trendelenburg体位腔镜手术中,PEEP呈阶梯式递增或递减对个体化PEEP的确定和对循环的影响相同,且每个PEEP水平持续1 min或2 min其结果无明显差异;但PEEP递减在PEEP阶梯变化过程中对肺复张的作用相对于递增更加有效和迅速。

Objective:To compare the effects of changing direction of positive end-expiratory pressure(PEEP)ladder and the duration of each PEEP level on the determination of individualized PEEP,pulmonary dynamic compliance and oxygenation in patients undergoing endoscopic surgery with Trendelenburg position.Methods:Sixty patients scheduled for endoscopic colorectal surgery under general anesthesia were randomly divided into increasing group and decreasing group,with 30 cases in each group.PEEP increased from 0 cmH_(2)O to 16 cmH_(2)O in the increasing group and decreased from 16 cmH_(2)O to 0 cmH_(2)O in the decreasing group,and the change gradient of PEEP in all patients was 2 cmH_(2)O.The end-expiratory dynamic pulmonary compliance(Cdyn)displayed on anesthesia machine at 1 min and 2 min under each PEEP level during the change of PEEP was recorded,and the PEEP at the maximum Cdyn was determined as the individualized PEEP.During the change of PEEP,if the invasive mean arterial pressure decreased more than 10%of the basic level,deoxyepinephrine was given to maintain the hemodynamic stability.Results:There was no significant difference in the number of patients who needed to be given deoxyepinephrine in the process of maintaining hemodynamic stability between the two groups(P>0.05).There was no significant difference in PaO_(2)/FiO_(2) between the two groups before and after PEEP ladder(P>0.05),there was no significant difference in PaO_(2)/FiO_(2) before and after PEEP ladder in the increasing group(P>0.05),but PaO_(2)/FiO_(2) after PEEP ladder was higher than that before PEEP ladder in the decreasing group(P<0.05).There was no significant difference in the individualized PEEP obtained by maintaining PEEP for 1 min and 2 min between the two groups(P>0.05).When the PEEP level was 12,14,16 cmH_(2)O at 1 min maintenance time and the PEEP level was 8,10,12,14 cmH_(2)O at 2 min maintenance time,the Cdyn value in decreasing group was significantly higher than that in increasing group(P<0.01).Conclusions:In patients undergoing endoscopic surgery with Trendelenburg position,the stepwise increase or decrease of PEEP has the same effect on the determination of individualized PEEP and circulation,and there was no significant difference between each PEEP level at 1 min or 2 min.However,the effect of PEEP decrease on lung recruitment in the process of PEEP ladder change is more effective and faster than that of PEEP increase.