Abstract

Background: The Physiological and Operative Severity Scoring system for enUmeration of Mortality and morbidity (POSSUM) and its modification, Portsmouth POSSUM scoring system has been proposed as risk adjusted surgical scoring system for standardizing method for the patient data, so as to allow the direct comparison in spite of differing patterns of population and referral patterns^(1,2). Application of Portsmouth POSSUM scoring system in developing countries like India especially in under developed areas like Chidambaram where most people belongs to poor socio economic status because of frequent attacks by cyclones, poverty being more since most of local residents are farmers and fisherman and resource availability being less and delayed presentation being more common because most areas being remote to health facilities is limited. Hence the prospective study was taken up to assess the validity of Portsmouth POSSUM scoring system and risk factors responsible for poor outcome.

Methods: 50 cases undergoing major abdominal surgeries in Department of General surgery, Rajah Muthiah Medical College and Hospital, Chidambaram were studied. The expected mortality rate was obtained using the formula. The observed and expected mortality ratio (O: E ratio) was then obtained by dividing the expected number of deaths with observed number of deaths in each category.  Chi square test with Yates correction was then applied to obtain the p value to note any significant difference between predicted and actual death. The distribution of both physiological and operative parameters between the two groups dead and alive was obtained by cross tabulation and the pattern was expressed by means of percentages. The distribution was then compared by using Chi-square test to find out any difference between the two groups with respect to the risk factor concerned. In case of continuous variables like Physiological score, operative score and predicted mortality, Independent samples t test have been applied to find out the difference between the two groups.

Results: In our study we assessed the validity of Portsmouth POSSUM in 50 major abdominal surgeries by comparing the observed and expected mortality rate. The predicted mortality was significantly higher among those died than those who were alive. The observed: expected ratio was found to be 1.The physiological score was found to be significantly different between the dead and alive, while the operative score was found to be similar between the two groups in our study. The physiological score was found to influence the outcome more than the operative score in the present study. The above results indicate that the Portsmouth POSSUM scoring system predicts the mortality accurately among the study participants.

Conclusion: The present study suggests that Portsmouth POSSUM is accurate predictor of postoperative mortality in our study population.

Keywords: P-POSSUM, Portsmouth POSSUM, major GI surgeries, mortality, surgical scoring audit.