Whether intraoperative positive end-expiratory pressure (PEEP) can reduce the risk of postoperative pulmonary complications remains controversial. We performed a systematic review of currently available literature to investigate whether intraoperative PEEP decreases pulmonary complications in anesthetized patients undergoing surgery.
We searched PubMed, Embase, and the Cochrane Library to identify randomized controlled trials (RCTs) that compared intraoperative PEEP versus zero PEEP (ZEEP) for postoperative pulmonary complications in adults. The prespecified primary outcome was postoperative pulmonary atelectasis.
Fourteen RCTs enrolling 1238 patients met the inclusion criteria. Meta-analysis using a random-effects model showed a decrease in postoperative atelectasis (relative risk [RR], 0.51; 95% confidence interval [CI], 0.35–0.76; trial sequential analyses [TSA]-adjusted CI, 0.10–2.55) and postoperative pneumonia (RR, 0.48; 95% CI, 0.27–0.84; TSA-adjusted CI, 0.05–4.86) in patients receiving PEEP ventilation. However, TSA showed that the cumulative Z-curve of 2 outcomes crossed the conventional boundary but did not cross the trial sequential monitoring boundary, indicating a possible false-positive result. We observed no effect of PEEP versus ZEEP ventilation on postoperative mortality (RR, 1.78; 95% CI, 0.55–5.70).
The evidence that intraoperative PEEP reduces postoperative pulmonary complications is suggestive but too unreliable to allow definitive conclusions to be drawn.
From the *Department of Anesthesiology, The First Hospital of Anhui Medical University, Hefei, China
†Department of Anesthesiology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China.
Accepted for publication August 1, 2019.
Funding: This work was supported by grant from the National Natural Science Foundation of China (No. 81671947, 81272142).
The authors declare no conflicts of interest.
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P. Zhang, L. Wu, and X. Shi contributed equally and share first authorship.
Reprints will not be available from the authors.
Address correspondence to Xin Lv, MD, PhD, Department of Anesthesiology, The First Hospital of Anhui Medical University, Hefei, 230022, China; and Department of Anesthesiology, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, 200433, China. Address e-mail to firstname.lastname@example.org.