Long term risk prediction in patients undergoing abdominal aortic aneurysm repair: the ultimate stress test of open repair

Physiologic component of the estimation of physiologic ability and surgical stress scoring system as a predictor of immediate outcome after elective open abdominal aortic aneurysm repair

BACKGROUND

Previous studies have shown a good predictive power of the risk scoring method, Estimation of Physiologic Ability and Surgical Stress, in predicting mortality after open elective aortic aneurysm repair. The aim of the present study was to evaluate the physiologic component of this method to assess mortality risk in a different geographic population from previously published reports.

METHODS

Operative, morbidity and mortality data were collected retrospectively from charts of patients submitted to elective open repair of an abdominal aortic aneurysm over an 8-year period. There were 214 patients, the median age was 70 (range: 48-91) years; 179 (83.6%) patients were men. The Preoperative Physiologic Risk Score (PRS), Surgical Stress Score, and Comprehensive Risk Score (CRS) values were categorized and compared with morbidity and mortality rates.

RESULTS

There were 27 deaths (12.6%), and 81 (37.9%) patients experienced a postoperative complication that required medical intervention. There was a significant statistical difference for the values of PRS and CRS for patients who survived (0.53/0.63, respectively) and for those who died (0.88/1.02, respectively), p < 0.0001 for both values. There is a strong correlation between PRS and CRS values and development of complications (p < 0.0001). Surgical Stress Score did not correlate as strongly to development of complications (p = 0.0028). For PRS, the area under the receiver-operator characteristic curve was 0.844 (95% confidence interval: 0.747-0.941) for mortality and 0.725 (95% confidence interval: 0.650-0.799) for morbidity. For CRS, the area under the curve was 0.812 (95% confidence interval: 0.734-0.891) for mortality and 0.719 (95% confidence interval: 0.645-0.792) for morbidity. There was also a significant positive correlation between length of hospital stay and PRS and CRS scores (p < 0.0001). In this study, it was found that renal impairment has a significant positive correlation with mortality (p = 0.0008), with an odds ratio of 4.3. In a multivariate regression analysis, renal impairment failed to increase the accuracy of the model when associated with the other parameters considered in PRS.

CONCLUSION

This study corroborates with the previous findings that the Estimation of Physiologic Ability and Surgical Stress model seems to be a promising method of predicting death and postoperative complications in patients undergoing open abdominal aortic aneurysm repair.

Can Laboratory Tests Predict the Prognosis of Patients after Endovascular Aneurysm Repair? Current Status and Future Directions

The purpose of this study was to determine what laboratory values predict the prognosis of patients after endovascular aneurysm repair (EVAR). MEDLINE and Cochrane Library databases were searched. This resulted in 13 relevant articles. Data were pooled, and meta-analyses were performed. A meta-analysis including 5,655 patients showed that preoperative serum creatinine > 1.5 mg/dL was a significant risk indicator for increased 30-day mortality (relative risk 3.0, 95% confidence interval 2.3–4.1, p < .0001). Four other studies showed that other cutoff values of creatinine or glomerular filtration rate can predict mortality and complications following EVAR. One study suggested that reduced preoperative hemoglobin is a risk indicator for reduced long-term survival. Increased serum creatinine, reduced glomerular filtration rate, and reduced hemoglobin are significant and strong predictors of mortality and complications after EVAR. Current evidence remains limited, and further research is needed to determine conclusively additional laboratory values that may predict the outcome of patients following EVAR.