Relationship Between Intraoperative Hypotension and Acute Kidney Injury After Living Donor Liver Transplantation: A Retrospective Analysis.

ABSTRACT

OBJECTIVE: Acute kidney injury (AKI) is common after liver transplantation (LT) and has a significant impact on outcomes. Although several risk factors for post-LT AKI have been identified, the effect of intraoperative hemodynamic status on post-LT AKI remains unknown. Therefore, the authors aimed to investigate the relationship between hemodynamic parameters during LT and postoperative AKI. DESIGN: A retrospective observational study. SETTING: University hospital. PARTICIPANTS: Patients who underwent living donor LT (n = 231). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Severe AKI (stages 2-3 according to recent guidelines) was the primary outcome. Multivariable logistic regression analysis was used to control for confounding variables to obtain the independent relationship between intraoperative hemodynamic parameters (mean arterial pressure [MAP] and cardiac index) and severe AKI. The prevalence of severe AKI was 30.7%. Nadir MAP during the surgery was independently predictive of severe AKI (adjusted odds ratio, 2.11 [95% confidence interval, 1.32-3.47] per 10-mmHg decrease; p = 0.002). Subgroup analyses based on various patient or operative variables and extensive sensitivity analyses showed substantially similar results. Severe hypotension (MAP<40 mmHg), even for fewer than 10 minutes, was related significantly to severe AKI (adjusted odds ratio, 3.80 [95% confidence interval, 1.17-12.30]; p = 0.026). In contrast, nadir cardiac index was not related significantly to severe AKI. CONCLUSIONS: The authors found an independent relationship between degree of intraoperative hypotension and risk of severe AKI in living donor LT recipients. Severe hypotension, even for a short duration, was related significantly to severe AKI.