Factors that affect the survival rate of patients with ruptured abdominal aortic aneurysms

There has been much discussion in the literature of factors that affect the mortality rate of patients who undergo repair of ruptured abdominal aortic aneurysms. Some studies have suggested restricting patient selection for repair on the basis of certain preoperative factors including age, increased creatinine level, low hemoglobin level, loss of consciousness, electrocardiographic changes, and preoperative cormorbid medical conditions. A retrospective review of 96 patients who underwent repair of a ruptured abdominal aortic aneurysm was performed to determine whether these factors would necessarily be applicable to all populations.

A retrospective chart review of all patients who underwent repair of a ruptured abdominal aortic aneurysm was performed over a study period of 20 years. Data was analyzed by both univariate and multivariate analysis.

The mean age of the patients was 73 years. The intraoperative mortality rate was 23%. The in-hospital mortality rate was 60.4%, with a 30-day mortality rate of 56.3%. By univariate analysis of various factors associated with the mortality rate, hemoglobin level, creatinine level, lowest preoperative and average intraoperative systolic blood pressure, packed red blood cells transfused, estimated blood loss, intraoperative urine output, and temperature were statistically significant. A history of loss of consciousness was also statistically significant. No preoperative comorbid medical conditions were significant, nor was age. On a multivariate analysis, preoperative factors of loss of consciousness, a lowest preoperative systolic blood pressure less than 90 mm Hg, a hemoglobin level less than 10 g/dl, and a creatinine level greater than 1.5 mg/dl were predictive of death. The effects of the hemoglobin level, creatinine level, and loss of consciousness on the mortality rate were strongest in patients who had a lowest preoperative systolic blood pressure greater than 90 mm Hg. In patients who had the sets of preoperative factors that were associated with a 100% mortality rate, there were intraoprative factors that influenced their death.

These findings suggest that the factors (loss of consciousness, creatinine level, hemoglobin level) that are predictive of death may be a reflection of shock in this patient population. Further studies should be directed to optimizing preoperative resuscitation. Patients who have a ruptured abdominal aortic aneurysm should not be denied therapy on the basis of any specific set of preoperative factors.