Estimating the possible predictors for survival
Possible predictors were assessed by two mainly used risk models for vascular surgery; Vascular Quality Initiative and Vascular Study Group of New England risk prediction models.78,9 . The combined possible predictors of these two risk models were analyzed in the current study as follows. The predefined patient demographics (age as a continuous variable, gender and comorbid factors such as diabetes, chronic obstructive pulmonary disease, concomitant cardiac disease) were identified. Urgent repair was defined as symptomatic aneurysm treated within 24-48 hours of admission. Preoperative renal insufficiency was defined as creatinine level ≥ 1.8 mg/dl and preoperative anemia was defined as hematocrit values below 30%. Furthermore, aneurysm diameter was categorized as < 6.0 cm or ≥ 6.0 cm.10