A systematic review of the Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity and its Portsmouth modification as predictors of post-operative morbidity and mortality in patients undergoing pancreatic surgery

BackgroundThe Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (POSSUM) model and its Portsmouth modification (P-POSSUM) are used extensively to predict postoperative mortality and morbidity in general surgery. The aim of this study was to undertake the first systematic review of the predictive value of these models in patients undergoing pancreatic surgery.MethodsEligible articles were identified by searches of electronic databases for those published from 1991 to 2012. Two independent reviewers assessed each study against inclusion and exclusion criteria. All data were specific to pancreatic surgery. Predictive value of morbidity and mortality were assessed by calculating observed/expected ratios.ResultsNine studies were included in the final review. The morbidity analysis included 8 studies (1,734 patients) of POSSUM with a weighted observed/expected ratio of .85. The mortality analysis included 5 studies (936 patients) of POSSUM and 4 studies (716 patients) of P-POSSUM. Weighted observed/expected ratios for mortality were .35 for POSSUM and 1.39 for P-POSSUM.ConclusionsPOSSUM overpredicted postoperative morbidity in patients undergoing pancreatic surgery. Both POSSUM and P-POSSUM failed to offer significant predictive value for mortality in pancreatic surgery, and more data collection in large populations undergoing pancreatic surgery are needed.