Intraoperative Optic Nerve Sheath Diameter as a Predictor of Early Tacrolimus Neurotoxicity after Living Donor Liver Transplantation.

Background: During liver transplantation, graft reperfusion triggers cerebral hyperemia, increases intracranial pressure, and disrupts the blood-brain barrier, thereby increasing the risk for immunosuppression neurotoxicity. Therefore, we tested the intraoperative optic nerve sheath diameter (ONSD) for predicting tacrolimus neurotoxicity after liver transplantation.

Basic Procedures: We prospectively included 100 adult patients who underwent living donor liver transplantation. The ultrasonographic ONSD 5 min after reperfusion was used as the index test, whereas the occurrence of early tacrolimus neurotoxicity was used as the reference. The area under the receiver operating characteristic curve (AUROC) was used to estimate the ONSD prediction accuracy. We reported the specificity and sensitivity of ONSD 5 and 30 min after reperfusion. Cutoffs were derived from the ROC curves. In addition, we used regression to control for confounders while testing the association between the ONSD and tacrolimus neurotoxicity.

Main Findings: The AUROC at T3 was 0.74 (95% confidence interval (CI), 0.63-0.85, P < 0.001). An ONSD of ≥6.4 mm at T3 had an 86% sensitivity (95% CI, 68%-96%) and 53% specificity (95% CI, 41%-65%). An ONSD of ≥6.4 mm at T3 had an adjusted odds ratio for tacrolimus neurotoxicity of 6.3 (95% CI, 1.9-21, P = 0.003).

Conclusions: This data indicates that intraoperative ultrasonic ONSD after reperfusion can predict tacrolimus neurotoxicity after liver transplantation.

Trial Registration: NCT03799770; registered on January 1st, 2019.