Intensive alveolar recruitment strategy in the post-cardiac surgery setting: one PEEP level may not fit all
Low tidal volume ventilation is now a standard of care in ICU patients and in high risk patients in the operating room (OR), since convincing evidence have been provided regarding its benefit on prognosis in these settings (1,2). PEEP setting is less straightforward in ARDS, and, while high PEEP levels are advocated in the more severely hypoxemic patients, the search for a reliable bedside tool to titrate PEEP in an individual ARDS patient is still ongoing (3). In the OR context, the recent PROVHILO trial failed to demonstrate any favorable effect on outcome of high PEEP as compared to low PEEP during open abdominal surgery (4). Recruitment maneuver are even more controversial, either during ARDS where the level of evidence is low, or in the OR where they are often used as a co-intervention in low tidal volume trials. Moreover, a great variability among trials testing recruiting maneuvers exists in terms of timing, frequency, duration, intensity and ventilatory mode, precluding any comparison or generalization of findings. Finally, uncertainties remain regarding the adverse effects of recruitment maneuvers, especially regarding hemodynamic tolerance and risk of ventilation-induced lung injury (VILI).