Renal Resistive Index and Myocardial Performance Index for Early Prediction of Acute Kidney Injury after Living Donor Liver Transplant

Background: Acute kidney injury (AKI) frequently arises as a complication after living donor liver transplantation (LDLT), affecting patient outcomes. Objective: This research assessed how well renal resistive index (RRI) and myocardial performance index (MPI) predict early postoperative AKI in LDLT recipients. Methods: A prospective observational study was conducted with 104 adult LDLT recipients at Mansoura University from September 2022 to June 2024. RRI and MPI were measured preoperatively and postoperatively using transabdominal sonography and transthoracic echocardiography respectively. AKI was determined according to the criteria set by the International Club of Ascites. The primary outcome was early postoperative AKI incidence, with secondary outcomes including RRI and MPI’s predictive accuracy. Results: Of 104 patients, 64 (61.5%) developed AKI. Postoperative RRI was significantly higher in the AKI group (0.744 ± 0.06 vs. 0.653 ± 0.05, p < 0.001), with a cutoff of ≥ 0.695 predicting AKI (sensitivity 82.8%, specificity 82.5%, AUC 0.891). Postoperative MPI was also higher (0.321 ± 0.04 vs. 0.282 ± 0.04, p < 0.001), with a cutoff of ≥0.286 (sensitivity 85.9%, specificity 57.5%, AUC 0.745). Preoperative RRI was predictive (cutoff ≥0.655, AUC 0.714), but preoperative MPI was not. Risk factors included higher BMI, diabetes, and intraoperative hypotension. Conclusion: RRI and MPI, particularly postoperative measurements, were effective predictors of early postoperative AKI in LDLT recipients, with RRI showing superior accuracy. These findings suggest that perioperative RRI and MPI monitoring could enhance AKI risk stratification and management, warranting further validation in larger studies.