中文摘要：

目的观察低水平呼气末正压（PEEP）在防治重症中毒机械通气呼吸机相关性肺炎中的作用。方法选取急诊2010年10月-2013年4月各类重症中毒机械通气患者共46例,按数字随机法分为两组,治疗组在机械通气时加用5cm H2O呼气末正压机械通气,对照组不加用呼气末正压,比较两组患者呼吸机相关性肺炎发生率。结果治疗组23例发生VAP3例,发生时间（5.80±1.56）d,机械通气时间（5.30±3.64）d,对照组23例VAP发生6例,发生时间为（3.10±1.43）d,机械通气时间为（8.40±4.58）d,两组比较差异有统计学意义（P〈0.01）;治疗组23例患者使用PEEP前平均动脉压（81±2.35）mm Hg、心率（66±1.24）/min、经皮血氧饱和度（90±2.47）%、氧分压（59±3.42）mm Hg、二氧化碳分压（45±2.75）mm Hg,使用PEEP后分别为（80±2.51）mm Hg、（68±2.31）次/min、（96±2.14）%、（97±4.26）mm Hg、（37±3.17）mm Hg;使用PEEP前后平均动脉压、心率无明显差异,经皮血氧饱和度、氧分压、二氧化碳分压,差异有统计学意义（P〈0.05）;46例患者治愈43例,死亡3例,死因主要为高龄合并多脏器功能衰竭,平均使用呼吸机时间为（6.4±3.26）d,治愈出院患者住院时间为（9.32±3.21）d。结论低水平PEEP对防治重症中毒患者呼吸机相关性肺炎有一定疗效。

英文摘要：

OBJECTIVE To observe the effect of low-level positive end-expiratory pressure（PEEP）on prevention of severe poisoning ventilator-associated pneumonia.METHODS Totally 46patients who underwent various severe poisoning mechanical ventilations in the emergency department from Oct 2010 to Apr were enrolled in the study and randomly divided into two groups,the treatment group received additional 5cm H2O positive end-expiratory pressure on the basis of mechanical ventilation,while the control group did not receive the positive end-expiratory pressure,then the incidence of VAP was compared between the two groups.RESULTS The VAP occurred in 3of 23cases of the treatment group and in 6 of 23cases of the control group;the onset time was（5.80±1.56）days in the treatment group,（3.10±1.43）days in the control group;the mechanical ventilation duration was（5.30 ±3.64）days in the treatment group,（8.40±4.58）days in the control group,the differences between the two groups were significant（P0.01）.Of the 23cases in the treatment group,the mean arterial pressure was（81 ±2.35）mm Hg before the use of PEEP,（80 ±2.51）mmHg after the use of PEEP;the heart rate was（66 ±1.24）times/min before the use of PEEP,（68±2.31）times/min after the use of PEEP;the transcutaneous oxygen saturation was（90±2.47）% before the use of PEEP,（96±2.14）%after the use of PEEP;the oxygen partial pressure was（59±3.42）mm Hg before the use of PEEP,（97±4.26）mm Hg after the use of PEEP;the carbon dioxide partial pressure was（45±2.75）mm Hg before the use of PEEP,（37±3.17）mm Hg after the use of PEEP;there was no significant difference in the mean arterial pressure or heart rate between before and after the use of PEEP,but the difference in the transcutaneous oxygen saturation,oxygen partial pressure,or carbon dioxide partial pressure between before and after the use of PEEP was significant（P0.05）.Of totally 46patients,43cases were cured,and 3cases died;the advanced age combined with multiple organs