Ruptured Abdominal Aortic Aneurysms: Factors Influencing Early Survival

Abstract

In this study we aimed to define relevant prognostic predictors for the outcome of surgical treatment of ruptured abdominal aortic aneurysms. The study included 406 consecutive patients treated between January 1991 and December 2003. There were 337 (83%) male and 69 (17%) female patients aged 67 +/- 7.5 years. Fourteen (3.5%) patients had aortocaval fistula whereas 4 (0.98%) had primary aortorenteric fistula caused by aneurysm rupture into the inferior vena cava or duodenum. Reconstruction included interposition of a tube graft (215-53%), aortobiiliac bypass (134-33%), and aortobifemoral bypass (58-14.3%). Findings on admission that significantly correlated with both intraoperative (13.5%) and total operative mortality (48.3%) were systolic blood pressure <95 mmHg, low diuresis, unconsciousness, cardiac arrest, leukocytes >14 x 10(9)/L, hematocrit <0.29%, hemoglobin <100 g/L, urea> 11 mmol/L, and creatinine >180 micromol/L. Intraoperative determinants of increased mortality were aortic cross-clamping time >47 min, duration of surgery >200 min, intraoperative blood loss >3500 mL, diuresis <400 mL, arterial systolic pressure <97.5 mmHg, and the need for aortobifemoral bypass. Respiratory complications and multisystem organ failure were significantly associated with lethal outcome in the postoperative period. Surgical treatment of ruptured abdominal aortic aneurysm was life-saving in 51.7% of patients. Variables significantly associated with mortality were unconsciousness, low systolic blood pressure, cardiac arrest, low diuresis, high urea and creatinine levels, signs of blood loss, and the need for aortobifemoral reconstruction. Short aortic cross-clamping and the total operation time, low intraoperative blood loss, and well-controlled diuresis and arterial pressure during surgery have improved survival. Therapeutic efforts should concentrate on intraoperative factors that are possible to correct, leading to better survival of these patients.