Respiratory failure & ventilation
Impact of positive end-expiratory pressure (PEEP) on V/Q mismatch according to patient position and recruitability: a clinical prospective study
Authors' conclusion
In patients with higher R/I ratio, PEEP 15 cm H2O improved V/Q mismatch in both supine and positions. In patients with lower R/I ratio, PEEP 15 cm H2O did not impact V/Q mismatch in supine position but significantly worsened it in prone position.
Study context
- Population
- Patients with moderate-to-severe acute respiratory distress syndrome (ARDS)consecutively enrolled
- Participants
- 50 patients
- Exposure
- PEEP 15 vs 5 cm H2O in supine and prone position, by recruitability
- Outcome
- V/Q mismatch at PEEP 15 vs 5 cm H2O in supine and prone position, by R/I ratio
Methodological detailsconsecutive enrolment, crossover of PEEP levels and positions
- Consecutive enrolment
- Crossover of PEEP levels and positions
Main finding
As reported in the abstract
V/Q mismatch
- Higher R/I ratio: PEEP 15 reduced shunt without significantly increasing dead space in both positions
- Lower R/I ratio, supine: shunt reduction accompanied by significant increase in dead space
- Lower R/I ratio, prone: PEEP 15 failed to reduce shunt while significantly increasing dead space
- PEEP 15 cm H2O vs PEEP 5 cm H2O: P < 0.001
- PEEP 15 cm H2O vs PEEP 5 cm H2O: P < 0.001
- PEEP 15 cm H2O vs PEEP 5 cm H2O: P = 0.078
- PEEP 15 cm H2O vs PEEP 5 cm H2O: P < 0.001
- Median [IQR]
Observational data: associations, not effects.
Further findings
Baseline recruitability (R/I ratio)
- Median R/I ratio, separating higher and lower R/I ratio
- 0.60 [0.38, 0.72]
Original publication
Impact of PEEP on V/Q mismatch according to patient position and recruitability: a clinical prospective study. Ann Intensive Care. Published 9 March 2026. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →