Effects of intraoperative positive end-expiratory pressure and fraction of inspired oxygen on postoperative oxygenation in dogs undergoing stifle surgery.

Objective: To compare the effects of fraction of inspired oxygen (FiO) with the addition of positive end-expiratory pressure (PEEP) during anesthesia on arterial oxygenation in the first 4 postoperative hours in dogs. We hypothesized that compared with dogs breathing FiO ≥ 0.95 and no PEEP (ZEEP), the use of intraoperative PEEP would improve postoperative oxygenation, and that the use of PEEP combined with an FiO of 0.