Intra-operative ventilation strategies and their impact on clinical outcomes: a systematic review and network meta-analysis of randomised trials.

Summary

Across 51 randomized trials, low tidal volume strategies consistently reduced postoperative pulmonary complications versus high tidal volume with zero PEEP. Low tidal volume with personalized or higher PEEP (with or without recruitment manoeuvres) provided additional benefit over high tidal volume/zero PEEP, and personalized PEEP modestly improved outcomes versus low PEEP under low tidal volume. Evidence certainty was generally moderate.

Key Findings

• Compared with high tidal volume/zero PEEP, low tidal volume strategies reduced postoperative pulmonary complications (RRs 0.44–0.65 across PEEP/recruitment combinations; moderate certainty).
• Low tidal volume with personalized PEEP likely reduced complications versus low tidal volume/low PEEP (RR 0.85, 95% CI 0.73–0.99).
• Benefits were observed across several acceptable PEEP levels, supporting flexibility in PEEP selection within lung-protective ventilation.

Clinical Implications

Adopt low tidal volumes with non-zero PEEP as default intra-operative ventilation for non-cardiothoracic surgery. Where feasible, personalize PEEP and consider recruitment manoeuvres, while monitoring hemodynamics and driving pressures.

Limitations

• Heterogeneity in PEEP titration methods and recruitment manoeuvre protocols across trials.
• Total sample size across studies not reported in abstract; applicability limited to non-cardiothoracic surgery.

Future Directions

Define standardized, clinically feasible PEEP personalization strategies and evaluate integration with driving pressure targets and hemodynamic outcomes.