Pulmonary complications after non-cardiac surgeries: temporal patterns and risk factors.

Background: Postoperative complications are the primary determinants of survival following major surgery. We aimed to characterize the early perioperative risk factors for postoperative pulmonary complications (POPCs) in patients undergoing major non-cardiac surgeries.

Methods: This study utilized a multicenter prospective observational cohort design. Adult patients undergoing non-cardiac surgeries and admitted to 21 Brazilian ICUs were screened for inclusion in the study. POPCs were defined as the presence of acute pulmonary oedema, nosocomial pneumonia, and extubation failure in the postoperative period.

Results: Of the 581 patients enrolled, 110 (19%) had at least one POPC, of whom 5% had acute pulmonary oedema, 10% extubation failure while 10% had pneumonia. Most cases of pulmonary oedema occurred in the first week after surgery, while pneumonia was more frequently a later occurrence. The mortality rate was significantly higher in the group with POPCs compared to the group of patients without POPCs (62% vs. 11%, RR: 5.1, 95% CI: 4.23-7.69; P < 0.001). A low functional capacity (RR: 4.6, 95% CI: 2.1-10.0), major surgery (RR: 3.6, 95% CI: 1.2-10.7), preoperative hemodynamic instability (RR: 3.4, 95% CI: 1.1-10.6), alcoholism (RR: 3.3, 95% CI: 1.0-10.7), unplanned surgery (RR: 2.3, 95% CI: 1.0-5.2), the SOFA score (RR: 1.1, 95% CI: 1.0-1.2), and increased central venous pressure (RR: 1.1, 95% CI: 1.0-1.1) were independent predictors of POPCs.

Conclusions: Pulmonary complications are common in intensive care units after major non-cardiac surgeries. Awareness of the risk factors for POPCs may help multidisciplinary teams develop strategies to prevent these complications.