RATIONALE: Prone positioning reduces mortality in severe ARDS patients. To date no evidence supports the use of prone positioning during venovenous extracorporeal oxygenation (ECMO).
OBJECTIVES: Aim of the study was to assess feasibility, safety and effect on oxygenation and lung mechanics of prone positioning during ECMO. As a secondary exploratory aim, we assessed the association between PP and hospital mortality.
METHODS: We performed a multicenter retrospective cohort study in six italian ECMO centers, including patients managed with prone positioning (PP) during ECMO support (prone group, four centers) and patients managed in the supine position (control group, two centers). Physiological variables were analyzed at 4 time points (supine before PP, start of PP, end of PP, supine after PP). The association between prone positioning and hospital mortality was assessed by multivariate analysis and propensity score matching.
RESULTS: 240 patients were included, 107 in the prone group and 133 in the supine group. Median duration of the 326 pronation cycles was 15 [12-18] hours. Minor reversible complications were reported in 6% of prone positioning maneuvers. Prone positioning improved oxygenation and reduced intrapulmonary shunt. Unadjusted hospital mortality was lower in the prone group (34 vs 50%, p=0.017). After adjusting for covariates, prone positioning remained significantly associated with a reduction of hospital mortality (OR=0.50, 95%CI: 0.29-0.87). 66 propensity score-matched patients were identified in each group. In this matched sample, patients who underwent pronation had higher ECMO duration (16 vs10 days, p-value=0.0344) but lower hospital mortality (30% vs 53%, p=0.0241).
CONCLUSION: Prone positioning during ECMO improved oxygenation and was associated with a reduction of hospital mortality.