Postoperative respiratory failure: pathogenesis, prediction, and prevention

This review discusses our present understanding of postoperative respiratory failure (PRF) pathogenesis, risk factors, and perioperative-risk reduction strategies.

PRF, the most frequent postoperative pulmonary complication, is defined by impaired blood gas exchange appearing after surgery. PRF leads to longer hospital stays and higher mortality. The time frame for recognizing when respiratory failure is related to the surgical-anesthetic insult remains imprecise, however, and researchers have used different clinical events instead of blood gas measures to define the outcome. Still, studies in specific surgical populations or large patient samples have identified a range of predictors of PRF risk: type of surgery and comorbidity, mechanical ventilation, and multiple hits to the lung have been found to be relevant in most of these studies. Recently, risk-scoring systems for PRF have been developed and are being applied in new controlled trials of PRF-risk reduction measures. Current evidence favors carefully managing intraoperative ventilator use and fluids, reducing surgical aggression, and preventing wound infection and pain.

PRF is a life-threatening event that is challenging for the surgical team. Risk prediction scales based on large population studies are being developed and validated. We need high-quality trials of preventive measures, particularly those related to ventilator use in both high risk and general populations.