Clinical Predictors of Postoperative Medical Complications After Major Abdominal Surgery: A Multicenter Hospital-Based Observational Study

Background and aim: Major abdominal surgery is associated with substantial postoperative morbidity, including pulmonary, renal, cardiovascular, and infectious complications. Identification of perioperative factors associated with postoperative medical complications may improve risk stratification and perioperative optimization. The present study aimed to identify predictors of postoperative medical complications in patients undergoing major abdominal surgery, with the goal of improving perioperative risk stratification and informing strategies to reduce postoperative morbidity. Methods: This multicenter prospective observational cohort study was conducted at two tertiary care hospitals in Lahore, Pakistan. Adult patients undergoing major abdominal surgery were enrolled consecutively over a 12-month period. The primary outcome was the occurrence of postoperative medical complications within 30 days of surgery. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of postoperative medical complications. Results: A total of 284 patients were included, of whom 96 (33.8%) developed postoperative medical complications. Pulmonary complications were the most common events, followed by acute kidney injury and systemic infection. Patients with complications had significantly longer hospital stays (11 vs. six days, p<0.001). On multivariable analysis, American Society of Anesthesiologists (ASA) ≥III, hypoalbuminemia, emergency surgery, prolonged operative duration, intraoperative hypotension, and blood transfusion were independently associated with postoperative medical complications. Conclusions: Postoperative medical complications remain common after major abdominal surgery. Both patient-related and perioperative factors were independently associated with postoperative morbidity. Early identification of high-risk patients and optimization of modifiable perioperative factors may help reduce postoperative medical complications and improve surgical outcomes.