POSSUM and P-POSSUM Overpredict Mortality for Carotid Endarterectomy

• Published in: European journal of vascular and endovascular surgery Vol. 23; no. 3; pp. 209 - 211
• Main Authors: Kuhan, G, Abidia, A.F, Wijesinghe, L.D, Chetter, I.C, Johnson, B.F, Wilkinson, A.R, Renwick, P.M, McCollum, P.T
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2002
• Subjects: Adult; Aged; Aged, 80 and over; Carotid Artery Diseases - mortality; Carotid Artery Diseases - surgery; Carotid endarterectomy; Comparative audit; Endarterectomy, Carotid - mortality; Female; Humans; Linear Models; Logistic Models; Male; Middle Aged; Outcome Assessment (Health Care); P-POSSUM; POSSUM; Predictive Value of Tests; Prospective Studies; Retrospective Studies; Carotid endarterectomy; Comparative audit; POSSUM; P-POSSUM
• ISSN: 1078-5884; 1532-2165
• DOI: 10.1053/ejvs.2001.1557

Objectives: the aim was to test the predictive accuracy of POSSUM and P-POSSUM on patients undergoing CEA. Design: retrospective and prospective study. Materials: 499 CEAs performed by four vascular surgeons from a single unit from 1992–99. The median age was 68 (range 38–86) and 60% were men.Methods : physiological parameters, operative parameters and the 30-day mortality were collected. Predicted mortality for each patient was calculated using POSSUM and P-POSSUM equations. Patients were stratified into risk groups and observed and predicted deaths were compared. Accuracy of the prediction was assessed using chi-squared analysis. Results: the observed 30-day mortality was 1.8% (9/499). The predicted deaths using POSSUM and P-POSSUM analysis were 49 and 25 respectively compared to nine observed deaths. There was significant evidence of lack of fit of both models in predicting mortality (chi-squared analysis, p<0.05). Conclusions: POSSUM and P-POSSUM overpredict mortality and are unsuitable for comparative audit of CEA. Models developed specific for CEA might accurately predict mortality.