title: Comparison of risk-scoring methods in predicting the immediate outcome after elective open abdominal aortic aneurysm surgery.
abstract: OBJECTIVE
  The aim of this study was to apply three simple risk - scoring systems to prospectively collected data on all elective open Abdominal Aortic Aneurysm (AAA) operations in the Cambridge Academic Vascular Unit over a 6 - year period (January 1998 to January 2004), to compare their predictive values and to evaluate their validity with respect to prediction of mortality and post-operative complications.
  
  
  METHODS
  204 patients underwent elective open infra-renal AAA repair. Data were prospectively collected and risk assessment scores were calculated for mortality and morbidity according to the Glasgow Aneurysm Score (GAS), VBHOM (Vascular Biochemistry and Haematology Outcome Models) and Estimation of Physiologic Ability and Surgical Stress (E-PASS).
  
  
  RESULTS
  The mortality rate was 6.3% (13/204) and 59% (121/204) experienced a post-operative complication (30-day outcome). For GAS, VBHOM and E-PASS the receiver operating characteristics (ROC) curve analysis for prediction of in-hospital mortality showed area under the curve (AUC) of 0.84 (95% confidence interval [CI], 0.76 to 0.92; p<0.0001), 0.82 (95% CI, 0.68 to 0.95; p=0.0001) and 0.92 (95% CI, 0.87 to 0.97; p<0.0001) respectively. There were also significant correlations between post-operative complications and length of hospital stay and each of the three scores, but the correlation was substantially higher in the case of E-PASS.
  
  
  CONCLUSIONS
  All three scoring systems accurately predicted the risk of mortality and morbidity in patients undergoing elective open AAA repair. Among these, E-PASS seemed to be the most accurate predictor in this patient population.
authors.affiliation: Cambridge Vascular Unit, Cambridge University Hospital NHS Foundation Trust, Cambridge, UK.
authors.forename: T Y
authors.initials: TY
authors.lastname: Tang
authors.forename: S R
authors.initials: SR
authors.lastname: Walsh
authors.forename: T R
authors.initials: TR
authors.lastname: Fanshawe
authors.forename: V
authors.initials: V
authors.lastname: Seppi
authors.forename: U
authors.initials: U
authors.lastname: Sadat
authors.forename: P D
authors.initials: PD
authors.lastname: Hayes
authors.forename: K
authors.initials: K
authors.lastname: Varty
authors.forename: M E
authors.initials: ME
authors.lastname: Gaunt
authors.forename: J R
authors.initials: JR
authors.lastname: Boyle
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000401:mortality* / Q000503:physiopathology / Q000601:surgery; D019540:Area Under Curve; D005260:Female; D006305:Health Status Indicators; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011379:Prognosis; D012372:ROC Curve; D018570:Risk Assessment; D012720:Severity of Illness Index; D013312:Stress, Physiological / Q000503:physiopathology