A few years ago an ARDS network study said no for mortality and ventilator free days. Two recent studies published in JAMA revisited the question. In neither study was there a difference in mortality. One study attributed a reduction in refractory hypoxemia to the high peep strategy and the other one demonstrated that the high peep strategy was associated with more ventilator free days and organ failure free days.
Two related editorials were published in the same issue. The one by Gattinoni and Caironi was favorable to the high PEEP strategy for patients with more severe hypoxemia. The other one by Chiche and Angus was more reserved, citing the difficulties in interpreting studies of complex interventions, and suggesting that high PEEP strategies may ultimately emerge in clinical practice.
Taken together, what do these studies mean for real world practice? In neither study did there appear to be harm, and effects on secondary endpoints were encouraging, so why not implement the strategy? For the LOV study, at least, the devil may be in the details. Their protocol involved recruitment maneuvers and allowed plateau pressures to rise as high as 40(!), pretty dicey stuff if you’re not an expert. This is the type of thing that will likely perform better in the hands of expert clinical trialists than in the community.
On the other hand, the protocol used by the Express investigators looks much more doable. I look forward to more discussion and expert opinion on this topic to help us synthesize these findings with what we knew before and to help us decide how to incorporate them into real world practice.
Retired Doc offers some perspective here.