Prone Positioning in Severe Acute Respiratory Distress Syndrome
The PROSEVA trial shows improved survival with prone positioning in patients affected by moderate/severe ARDS. Prone positioning resulted effective in patients with moderate/severe ARDS persisting after a 12–24 hours stabilization period, admitted to centers with proven experience with prone position. Patients were ventilated with protective ventilation (6 ml/kg) and a PEEP of about 10 cm H2O. Prone position sessions lasted for at least 16 hours, and patients randomized to prone position were kept supine only if their PaO2/FiO2 consistently improved. Improved survival was not associated with improvement in pH, PaCO2, or PaO2; therefore a “response” to prone position is not necessarily a marker of improvement. Incidence of complications did not differ significantly between the two groups, except for cardiac arrests, which was higher in the supine group.