Effect of driving pressure-guided positive end-expiratory pressure on respiratory mechanics and clinical outcomes in surgical patients: a systematic review and meta-analysis of randomized controlled trials

Intraoperative driving pressure-guided positive end-expiratory pressure (PEEP_dp) is effective for reducing postoperative pulmonary complications (PPCs). However, its impact on respiratory mechanics and clinical outcomes requires further elaboration. PubMed, the Cochrane Library, Web of Science and Embase were searched from inception to May 2024 for randomized controlled trials (RCTs) comparing the effect of PEEP_dp with conventional fixed positive end-expiratory pressure (PEEP) in patients undergoing surgery. The primary outcomes were the effects on the driving pressure (DP), static respiratory compliance and plateau pressure (<i>P</i>_plat). Secondary outcomes included the effects on common clinical outcomes and the incidence of PPCs. Risk ratios or mean differences were pooled using fixed- or random-effects models. Nineteen RCTs involving 3744 patients were included. The mean of PEEP_dp was 8.2 cmH₂O with 95% CI from 7 cmH₂O to 9.5 cmH₂O, while the median of PEEP in the conventional group was 5 cmH₂O with an interquartile range of 1 cmH₂O. Patients in the PEEP_dp group were ventilated with lower DP (mean: 10 cmH₂O, 95% CI [8.8, 11.1] vs. mean: 11.9 cmH₂O, 95% CI [10.6, 13.3]; <i>p</i> &lt; .00001), and increased respiratory compliance (mean: 46.4 ml/cmH₂O, 95% CI [42.1, 50.7] vs. mean: 39 ml/cmH₂O, 95% CI [35.2, 42.8]; <i>p</i> &lt; .0001) with nonsignificant <i>P</i>_plat. PEEP_dp did not significantly affect intensive care unit (ICU) admission, mortality or length of hospital and ICU stay (<i>p</i> &gt; .05), but it reduced the incidence of PPCs (<i>p</i> = .001). The benefits were especially evident in patients undergoing abdominal surgery, those with DP less than 10 cmH₂O or those with PEEP_dp ranging from 5 to 10 cmH₂O or when PEEP_dp was titrated via a stepwise increase method (<i>p</i> &lt; .05). PEEP_dp allows for ventilation with lower DP, improved static respiratory compliance and fewer PPCs. No significant effects were observed on broader clinical outcomes per current data.

术中驱动压导向呼气末正压（PEEP_dp）可有效降低术后肺部并发症（PPCs）的发生风险，但其对呼吸力学及临床结局的影响仍有待进一步阐明。本研究检索了PubMed、Cochrane图书馆、Web of Science及Embase数据库自建库至2024年5月的相关文献，纳入比较PEEP_dp与常规固定呼气末正压（PEEP）在手术患者中应用效果的随机对照试验（RCTs）。本研究的主要结局指标为驱动压（DP）、静态呼吸顺应性及平台压（P_plat）的变化情况，次要结局指标涵盖常见临床结局及PPCs的发生率。采用固定效应模型或随机效应模型合并风险比或均数差。本研究共纳入19项RCT，涉及3744例患者。PEEP_dp组的呼气末正压均值为8.2 cmH₂O，95%置信区间（CI）为7~9.5 cmH₂O；而常规对照组的PEEP中位数为5 cmH₂O，四分位间距为1 cmH₂O。与对照组相比，PEEP_dp组患者的驱动压更低（均值：10 cmH₂O，95%CI [8.8, 11.1] vs. 均值：11.9 cmH₂O，95%CI [10.6, 13.3]；p<0.00001），静态呼吸顺应性更高（均值：46.4 ml/cmH₂O，95%CI [42.1, 50.7] vs. 均值：39 ml/cmH₂O，95%CI [35.2, 42.8]；p<0.0001），而平台压无显著差异。PEEP_dp对重症监护病房（ICU）收治率、病死率、住院时长及ICU停留时长均无显著影响（p>0.05），但可降低PPCs的发生率（p=0.001）。亚组分析显示，在腹部手术患者、基线驱动压<10 cmH₂O的患者、PEEP_dp设置为5~10 cmH₂O的患者，以及采用逐步递增法滴定PEEP_dp的研究中，上述获益更为显著（均p<0.05）。综上，PEEP_dp可使患者采用更低的驱动压进行机械通气，改善静态呼吸顺应性，并减少PPCs的发生。基于现有数据，其对其他广泛临床结局无显著影响。