To the Editor:
The recently published article by Mathis et al.1 showed that the use of an intraoperative lung protective ventilation bundle is associated with a lower rate of postoperative pulmonary complications, but when each strategy of the bundle was individually analyzed, only lower modified driving pressure was coincident with this result. Furthermore, the use of median positive end-expiratory pressure (PEEP) greater than or equal to 5 cm H2O had an adjusted odds ratio (95% CIs) greater than 1 (1.18, 0.91 to 1.53). What does this mean? Is the use of this level of PEEP hazardous for our patients? It eventually could be. Optimal PEEP during surgery widely vary among patients and its individualization improves postoperative respiratory outcomes.2 High PEEP could cause hyperdistention of lung units leading to pulmonary complications, but low PEEP could induce collapse of them resulting in the same undesirable effect. Although the study was not designed to, it certainly highlights the fact that PEEP isn’t innocuous. Individual PEEP titration is not a standardized practice in the operation room and until we find out how to solve this, we should be prudent when setting PEEP.
The author declares no competing interests.