Predictive power of Mannheim Peritonitis Index.

Abstract

To evaluate Mannheim Peritonitis Index (MPI) in predicting outcome in patients with secondary peritonitis and to assess each risk factor independently regarding its contribution towards final outcome. Prospective analytical study. Surgical Unit-II of Rawalpindi General Hospital, from December 1999 to January 2001. One hundred and twenty-six patients who presented to the department with secondary peritonitis were included in the study. MPI score was calculated for each patient on a pre-designed proforma and the patients were followed-up till death or discharged from the hospital. Death was the main outcome measure against which the MPI scores were analyzed under two categories; (i) score > or = 26 and < 26 (ii) scores < 21, 2-29, and > 29. Data was analyzed on software SPSS (version 11.0). Chi-square test was used to assess any significant association between scores and outcome. Odds ratios were calculated for individual risk factors. Mortality rate for MPI score > or = 26 was 28.1% while for scores less than 26 it was 4.3%. For MPI scores pound 20 mortality rate was 1.9%, for scores 21-29 it was 21.9% and for score 30 or more it was 28.1%. Chi-square showed significant association between mortality and increasing MPI score (p < 0.01). Odd ratios calculated were significant for age > 50 years, malignancy, organ failure, pre-operative duration of peritonitis > 24 hours and cloudy, purulent exudate. Increasing MPI score is strongly associated with outcome in secondary peritonitis.