Prognostic scoring in ruptured abdominal aortic aneurysm: A prospective evaluation
Presented at the Forty-second World Congress of Surgery of the International Society of Surgery, Montréal, Québec, Canada, August 26-30, 2007.
Received 8 June 2007; accepted 18 October 2007.
Background
Prospective validation of prognostic scoring systems for ruptured abdominal aortic aneurysm (AAA) is lacking. This study assesses the validity of three established risk scores and a new prognostic index.
Method
Patients admitted with ruptured AAA during a 26-month period (August 2002-December 2004) were recruited prospectively. The Glasgow Aneurysm Score (GAS), Hardman Index, Physiological and Operative Severity Score for enUmeration of Mortality and Morbidity (POSSUM) scores, and the Edinburgh Ruptured Aneurysm Score (ERAS) were recorded and related to outcome.
Results
During the study period, 111 patients were admitted with ruptured AAA. Of these, 84 (76%) underwent attempted operative repair and were included in the study; 37 (44%) died after operation. The GAS, Hardman Index, and the ERAS were statistically related to mortality. However, analysis by receiver-operator characteristic curve revealed the ERAS to have an area under the curve (AUC) of 0.72 (95% confidence interval [CI], 0.61-0.83). The vascular (V)-POSSUM and ruptured AAA (RAAA)-POSSUM models had an AUC of 0.70 (95% CI, 0.59-0.82). The Hardman Index and GAS had an AUC of 0.69 (95% CI, 0.57-0.80) and 0.64 (95% CI, 0.52-0.76), respectively. Although the V-POSSUM equation predicted mortality effectively (P = .086), the RAAA-POSSUM derivative demonstrated a significant lack of fit (P = .009).
Conclusion
Prospective validation shows that the Hardman Index, GAS, and V-POSSUM and RAAA-POSSUM scores do not perform well as predictors for death after ruptured AAA. The ERAS accurately stratifies perioperative risk but requires further validation.
aEdinburgh Vascular Surgical Service, Clinical & Surgical Sciences (Surgery), University of Edinburgh, Edinburgh, Scotland
bDepartment of General Practice & Primary Care, University of Aberdeen, Aberdeen, Scotland.
Correspondence: Andrew Tambyraja, Clinical & Surgical Sciences (Surgery), Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh, EH16 4SA UK.
ABSTRACT