Optimal Positive End Expiratory Pressure Levels in Ventilated Patients Without Acute Respiratory Distress Syndrome: A Bayesian Network Meta-Analysis and Systematic Review of Randomized Controlled Trials

Background: To find the optimal positive end expiratory pressure (PEEP) in mechanical ventilated patients without Acute Respiratory Distress Syndrome (ARDS), we conducted a Bayesian network meta-analysis and systematic review of randomized controlled trials (RCTs) comparing different level of PEEP based on a novel classification of PEEP level: ZEEP group (PEEP = 0 cm H2O); lower PEEP group (PEEP = 1-6 cm H2O); intermediate PEEP group (PEEP = 7-10 cm H2O); higher PEEP group (PEEP > 10 cm H2O). & nbsp; Result: Twenty eight eligible studies with 2,712 patients were included. There were no significant differences in the duration of mechanical ventilation between higher and intermediate PEEP (MD: 0.020, 95% CI: -0.14, 0.28), higher and lower PEEP (MD: -0.010, 95% CI: -0.23, 0.22), higher PEEP and ZEEP (MD: 0.010, 95% CI: -0.40, 0.22), intermediate and lower PEEP (MD: -0.040, 95% CI: -0.18, 0.040), intermediate PEEP and ZEEP (MD: -0.010, 95% CI: -0.42, 0.10), lower PEEP and ZEEP (MD: 0.020, 95% CI: -0.32, 0.13), respectively. Higher PEEP was associated with significantly higher PaO2/FiO2 ratio(PFR) when compared to ZEEP (MD: 73.24, 95% CI: 11.03, 130.7), and higher incidence of pneumothorax when compared to intermediate PEEP, lower PEEP and ZEEP (OR: 2.91e + 12, 95% CI: 40.3, 1.76e + 39; OR: 1.85e + 12, 95% CI: 29.2, 1.18e + 39; and OR: 1.44e + 12, 95% CI: 16.9, 8.70e + 38, respectively). There was no association between PEEP levels and other secondary outcomes. & nbsp; Conclusion: We identified higher PEEP was associated with significantly higher PFR and higher incidence of pneumothorax. Nonetheless, in terms of other outcomes, no significant differences were detected among four levels of PEEP. & nbsp;

Automated summary

In mechanically ventilated patients without ARDS, higher PEEP was associated with significantly higher PaO2/FiO2 ratio and increased incidence of pneumothorax. However, no significant differences were observed among the four levels of PEEP in terms of other outcomes.