Ruptured abdominal aortic aneurysm. Predictors of survival in 229 consecutive surgical patients.

BACKGROUND AND PURPOSE

A ruptured abdominal aortic aneurysm is one of the most urgent surgical conditions with high mortality. The aim of the present study was to define relevant prognostic predictors for the outcome of surgical treatment.

PATIENTS AND METHODS

This study included 229 subsequent patients (83% males, 17% females, age 67.0 +/- 7.5 years) with a ruptured abdominal aortic aneurysm. Before surgery, all patients underwent clinical examination, ultrasonography was performed in 78.6% (mean aneurysm diameter 73 mm, range 40-100 mm), computed tomography (CT) scan in 16.2%, magnetic resonance imaging (MRI) in 0.9%, and angiography in 12.6% of patients. The aneurysm was infrarenal in 74%, juxtarenal in 12.3%, suprarenal in 6.8%, and thoracoabdominal in 6.8% of patients. Types of rupture were retroperitoneal (65%), intraperitoneal (26.8%), chronic (3.8%), rupture into vena cava inferior (3.2%), and into duodenum (0.6%). Reconstruction included interposition of Dacron graft (53%), aortobiiliac bypass (32.8%), and aortobifemoral bypass (14.2%).

RESULTS

Findings on admission that significantly correlated with both intraoperative (13.5%) and total intrahospital mortality (53.7%) 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 micro mol/l. Intraoperative determinants of increased mortality were: aortic cross-clamping time > 47 min, duration of surgery > 200 min, intraoperative blood loss > 3,500 ml, diuresis < 400 ml, arterial systolic pressure < 97.5 mmHg, and the need for aortobifemoral bypass. Respiratory complications and multisystem organ failure were associated with a lethal outcome in the postoperative period.

CONCLUSION

Surgical treatment of ruptured abdominal aortic aneurysm was life-saving in 46.3% of patients. Hypotension, low diuresis, high urea and creatinine levels, signs of blood loss, unconsciousness, cardiac arrest, and the need for aortobifemoral reconstruction predicted poor outcome. Short aortic cross-clamping and total operation time, low intraoperative blood loss, and well-controlled diuresis and arterial pressure during surgery have improved survival.