Prone positioning and acute respiratory distress syndrome after cardiac surgery: a feasibility study

Abstract

Objective: To determine the feasibility, safety, and efficacy on PaO(2)/F(I)O(2) ratio of prone positioning (PP) for acute respiratory distress syndrome (ARDS) after cardiac surgery.

Design: Retrospective review of information entered prospectively in the authors' database.

Setting: A private community nonteaching hospital.

Participants: Sixteen patients who developed ARDS after cardiac surgery from January 2004 through June 2005.

Interventions: PP to improve oxygenation.

Measurements and main results: After a median duration of 18 (range, 14-27) hours in PP, PaO(2)/F(I)O(2) improved in 14 (87.5%) patients. For the entire population, median PaO(2)/F(I)O(2) rose from 87 (range, 56-161) before PP to 194 (range, 94-460; p < 0.05) after it. After supine repositioning (SR), PaO(2)/F(I)O(2) declined to 146 (range, 72-320; not significant). PaO(2)/F(I)O(2) at the end of PP and 1 day after SR were comparable, respectively, 194 (range, 94-460) and 184 (range, 105-342). No severe complication was associated with PP, but 5 patients developed pressure sores and 2 others had superficial sternal wound infections. Intensive care unit mortality of 37.5% reflected the number of organ failure(s); there were no deaths with 2 failures, and 60% with > or = 3 organ failures died (p = 0.03). Mortality rates were comparable regardless of whether patients were PaO(2)/F(I)O(2) responders or their PaCO(2) decreased by > or = 1 mmHg.

Conclusion: PP to treat ARDS after cardiac surgery is feasible, safe, and can efficiently improve oxygenation. Measures to prevent pressure sores are mandatory.

Fig 1

Median (filled circle) and individual evolutions of (A) PaO₂/F_IO₂ ratios and (B) PaCO₂ from just before to during PP and 1 hour and 1 day after SR; *p < 0.05 versus baseline PaO₂/F_IO₂.