Publication:

Study on evaluation of P-POSSUM scoring system in patients undergoing exploratory laparotomy

Background Emergency exploratory laparotomy carries substantially higher morbidity and mortality than elective surgery, and accurate risk stratification is essential for perioperative decision-making, patient counselling and surgical audit. The Portsmouth Physiological and Operative Severity Score for the enumeration of Mortality and Morbidity (P-POSSUM) is widely used for this purpose, but its performance in Indian tertiary surgical units requires local validation. This study aimed to evaluate the validity of P-POSSUM in predicting 30-day postoperative mortality and to characterize the complication profile in patients undergoing emergency exploratory laparotomy.

Methods This prospective observational study was conducted over two years (November 2023 to October 2025) in the Department of Surgery of a tertiary teaching hospital in Northern Maharashtra. A total of 134 patients aged 13 years or older undergoing emergency exploratory laparotomy were enrolled by convenience sampling. Preoperative physiological and intraoperative operative severity variables were recorded and P-POSSUM scores calculated using the standard logistic regression equation. Observed 30-day mortality was compared with P-POSSUM-predicted mortality, and observed-to-expected (O:E) ratios were calculated. Associations between clinical parameters and mortality were assessed using the chi-square test.

Results The mean age was 56.25±15.04 years, with a male predominance (53.7%). Perforation peritonitis (41.79%) was the commonest diagnosis, followed by acute intestinal obstruction (29.10%) and appendicular perforation (20.90%). The mean physiological score was 12.05±5.06, operative score 9.31±3.36, and mean predicted mortality was 33.72±24.39%. Overall observed mortality was 23.88% (32/134) compared with an expected mortality of 33.72%, giving an O:E ratio of approximately 0.71, indicating that P-POSSUM overestimated mortality in this surgical cohort. Physiological score >18, higher operative severity, greater blood loss, degree of peritoneal soiling and presence of malignancy were significantly associated with mortality (p<0.05). Postoperative complications occurred in 59.7% of patients, most commonly sepsis (20.90%) and renal failure (19.40%); 63.43% required ICU admission and 40.30% required ventilatory support.

Conclusions P-POSSUM remains a clinically useful risk-stratification tool for patients undergoing emergency exploratory laparotomy in an Indian tertiary surgical unit, but it systematically overestimates mortality, indicating a need for population-specific recalibration to improve its predictive accuracy and surgical audit utility.