A model for national outcome audit in vascular surgery

Objective: the aim was to model vascular surgical outcome in a national stu dy using POSSUM scoring. Methods: one hundred and twenty-one British and Irish surgeons completed da ta questionnaires on patients undergoing arterial surgery under their care (mean 12 patients, range 1-49) in May/June 1998. A total of 1480 completed data records were available for logistic regression analysis using P-POSSUM methodology. Information collected included all POSSUM data items plus oth er factors thought to have a significant bearing on patient outcome: "extra items". The main outcome measures were death and major postoperative compl ications. The data were checked and inconsistent records were excluded. The remaining 1313 were devided into two sets for analysis. The first "trainin g" set was used to obtain logistic regression models that were applied pros pectively to the second "test" dataset. Results: using POSSUM data items alone, it was possible to predict both mor tality and morbidity after vascular reconstruction using P-POSSUM analysis. The addition of the "extra items" found significant in regression analysis did not significantly improve the accuracy of prediction. It was possible to predict both mortality and morbidity derived from the preoperative physi ology components of the POSSUM data items alone. Conclusion: this study has shown that P-POSSUM methodology can be used to p redict outcome after arterial surgery across a range of surgeons in differe nt hospitals and could form the basis of a national outcome audit. It was a lso possible to obtain accurate models for both mortality and major morbidi ty from the POSSUM physiology scores alone.