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

Abstract

Background: 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.

Methods: 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 (P_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.

Results: 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]; p < .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]; p < .0001) with nonsignificant P_plat. PEEP_dp did not significantly affect intensive care unit (ICU) admission, mortality or length of hospital and ICU stay (p > .05), but it reduced the incidence of PPCs (p = .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 (p < .05).

Conclusions: 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.

Keywords: Respiratory mechanics; driving pressure; intraoperative lung protective ventilation; lung injury; positive end-expiratory pressure.

Figure 1.

Flowchart of selection process in this systematic review. PPCs: postoperative pulmonary complications; ICU: intensive care unit.

Figure 2.

Effect of PEEP_dp on respiratory mechanics. PEEP: positive end expiratory pressure; DP: driving pressure.

Figure 3.

Effect of PEEP_dp on clinical outcomes. PEEP: positive end expiratory pressure; DP: driving pressure; ICU: intensive care unit.