Risk factors for postoperative pneumonia after general and digestive surgery: a retrospective single-center study

Purpose: Pneumonia is the second-most common complication in postoperative patients and is associated with significant morbidity and high costs of care. We aimed to determine the risk factors for pneumonia after general and digestive surgery. Methods: The medical records of 1,016 patients who underwent general and digestive surgery between January 2016 and March 2019 in our hospital were reviewed. Results: Of the 1,016 patients, 67 (6.6%) developed postoperative pneumonia. The multivariate analysis showed that significant predictors of postoperative pneumonia were a poor Eastern Cooperative Oncology Group performance status (ECOG-PS), low forced vital capacity and low forced expiratory volume in one second in the spirometry test, malnutrition (low serum albumin levels and low controlling nutritional status scores and prognostic nutritional index [PNI] values), esophagectomy, upper gastrointestinal surgery, and nonlaparoscopic surgery. Of these factors, the combination of PNI and ECOG-PS clearly stratified patients into low-, intermediate-, and high-risk groups with respect to developing postoperative pneumonia (area under the curve: 0.709). Conclusions: Although postoperative pneumonia is associated with many clinical variables, active medical intervention for the prevention of pneumonia in patients with multiple risk factors can improve the postoperative course. In particular, perioperative nutritional care may prevent postoperative pneumonia in patients with malnutrition and a poor PS.