Perioperative hemoglobin concentrations are associated with acute kidney injury after deceased donor liver transplantation

Background: Acute kidney injury (AKI) is common after orthotopic liver transplantation (OLT). In major surgery, anemia has been associated with postoperative AKI. Although patients undergoing OLT frequently suffer from anemia, its impact on postoperative AKI remains unclear. We performed a single-center retrospective study including 724 patients undergoing their first OLT between January 2004 and December 2019 at the Medical University of Vienna. We evaluated whether perioperative hemoglobin concentrations were associated with postoperative AKI, renal replacement therapy, or mortality. Preoperative hemoglobin concentrations were 10.9 ( ± 2.1) g/dL in patients with AKI after OLT and 11.5 ( ± 2.1) g/dL in those without. Higher preoperative hemoglobin concentrations were associated with a lower probability of AKI (OR 0.847; P < 0.001) and a decreased probability of developing a higher AKI stage (OR: 0.895; P = 0.002). Stage 3 AKI was associated with increased 1-year (OR: 1.909; P < 0.001) and overall mortality (HR: 1.420; P = 0.037). Higher nadir hemoglobin concentrations within 48 h after OLT were associated with a lower probability of AKI (OR: 0.806; P = 0.033) and a decreased probability of developing a higher AKI stage (OR: 0.782; P < 0.001). In conclusion, higher perioperative hemoglobin concentrations were associated with a lower probability of AKI after OLT. Severe AKI was associated with an increased mortality.