Evaluation of Predictive Value of P-POSSUM Score in Patients Operated for Acute Abdomen and Comparison of Scoring at Admission and Pre-operatively

Abstract

Physiological and operative severity score for enumeration of mortality and morbidity (POSSUM), as reported by Copeland et al. (Br J Surg 78: 355–60, 1991) [1] and its Portsmouth modification (P-POSSUM) [2], as reported by Whiteley et al. (Br J Surg 83:812–15, 1996), remain one of the most widely accepted risk assessment scoring system in surgical patients and helps in apprising both the surgeon and the relatives with the involved risk. They have been extensively studied since their development for various surgical procedures, and though most aspects of the scoring are standardized, the timing of physiological scoring is variable (admission vs. pre-operatively) in most of the studies. Hence, we aim to evaluate the predictive value of the score in the defined patients in our setup and also to evaluate which timing of scoring is more accurate, whether at the time of admission or pre-operatively after initial resuscitation. One hundred patients, who underwent surgery for acute abdomen from November 2016 to March 2018 at our institute, were studied. Mortality and morbidity risk were calculated for each P-POSSUM score with physiological scoring done twice, i.e., at admission and pre-operatively. The ratio of observed to predicted death and morbidity (O:E) were calculated and compared for both scores using chi-square test. Area under the curve (AUC) analysis was used to compare the efficacy of both the scores. An observed to expected (O:E) ratio of 0.88 and 1.00 was obtained for mortality with physiological scoring at admission and pre-operatively. Similarly, the O:E values for morbidity were 0.85 and 0.87 respectively. P-POSSUM was found to give an accurate prediction of both mortality and morbidity in patients operated for acute abdomen. Moreover, physiological scoring done with pre-operative variables is superior in comparison to scoring at the time of admission and is a better predictor of outcome.