BACKGROUND AND OBJECTIVES: Extensive abdominal surgery is associated with the risk of postoperative pulmonary complications. This study aims to explore the incidence and risk factors for developing postoperative pulmonary complications after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy and to analyze how these complications affect overall survival.

METHODS: Data were collected on 417 patients undergoing surgery between 2007 and2017 at Uppsala University Hospital, Sweden. Postoperative pulmonary complications were graded according to the Clavien-Dindo classification system where Grade ≥ 3 was considered a severe complication. A logistic regression analysis was used to analyze risk factors for postoperative pulmonary complications and a Cox proportional hazards model to assess impact on survival.

RESULTS: Seventy-two patients (17%) developed severe postoperative pulmonary complications. Risk factors were full thickness diaphragmatic injury and/or diaphragmatic resection [OR 5.393, 95% CI 2.924-9.948, p = < 0.001]. Severe postoperative pulmonary complications, in combination with non-pulmonary complications, contributed to decreased overall survival [HR 2.285, 95% CI 1.232-4.241, p = 0.009].

CONCLUSIONS: Severe postoperative pulmonary complications were common and contributed to decreased overall survival. Full thickness diaphragmatic injury and/or diaphragmatic resection were the main risk factors. This finding emphasizes the need for further research on the mechanisms behind pulmonary complications and their association with mortality.