Predicting Persistent Renal Failure Necessitating Dialysis in Patients Undergoing Elective, Open Thoracoabdominal Aortic Aneurysm Repair.

BACKGROUND

Acute renal failure remains a significant complication after open thoracoabdominal aortic aneurysm (TAAA) repair and is associated with high mortality. Rigorous risk estimation for this complication is vital for these patients.

METHODS

Data were analyzed from 2809 patients who underwent elective, open TAAA repair between 1986 and 2024 at a single practice. Persistent renal failure was defined as the need for dialysis at time of operative discharge (including any hospital transfer) or death. The effectiveness of 4 predictive models-multivariable logistic regression, random forest, support vector machine, and gradient boosting machine-was compared by using the test C statistic (C) from an 80:20, 1000-iteration cross-validation scheme. The regression model was converted into a nomogram for patient counseling.

RESULTS

Persistent renal failure necessitating dialysis developed in 158 (5.6%) patients, of whom 90 (57.0%) experienced operative death. Of the 4 models, the regression model was the most predictive (C = 0.75 [0.72-0.77]). The highest performing machine learning model, the gradient boosting machine, had similar efficacy (C = 0.73 [0.70-0.76]). The final regression model included 8 factors: Crawford extent II repair (odds ratio [OR], 1.86; P = .001), chronic aortic dissection (OR, 1.72; P = .01), symptomatic aneurysm (OR, 1.47; P = .03), maximum distal aortic diameter ≥6 cm (OR, 1.44; P = .06), age (OR, 1.04; P < .001), preoperative estimated glomerular filtration rate (OR, 0.97; P < .001), male sex (OR, 0.65; P = .01), and Crawford extent I repair (OR, 0.43; P = .004).

CONCLUSIONS

The regression model, built using preoperative factors, effectively predicted persistent renal failure necessitating dialysis in patients undergoing elective, open TAAA repair. We converted this model into a nomogram to aid in preoperative counseling.