Acute kidney injury after liver transplantation: incidence and mortality

Patients undergoing orthotopic liver transplantation often present with acute kidney injury (AKI) in the postoperative period. It has been associated with a greater number of complications and high mortality rates. The goal of this study was to determine the incidence of AKI during the early posttransplant period and mortality in patients undergoing orthotopic liver transplantation in our hospital.

In this retrospective cohort study, we reviewed the medical records of all patients aged >18 years undergoing liver transplantation from April 2008 to April 2011. The exclusion criteria were a glomerular filtration rate (estimated by using the Modification of Diet in Renal Disease formula) <60 mL/min/1.73 m(2) or AKI at the time of transplantation. AKI was defined as an increase ≥50% from preoperative baseline serum creatinine levels during the hospitalization period.

Of 113 selected patients, 78 (69%) were male. The mean age was 54.03 ± 9.38 years. The mean preoperative baseline creatinine level was 0.94 ± 0.15 mg/dL, and the estimated glomerular filtration rate was 87.09 ± 19.67 mL/min/1.73 m(2). The mean calculated Model for End-Stage Liver Disease score was 13. Hepatitis C serology was present in 70.8%, hepatitis B in 11.5%, hepatocellular carcinoma in 75.2%, and alcohol abuse in 31.9% of patients. The incidence of AKI was 56.6% (64 of 113 patients). The main risk factors for AKI were Model for End-Stage Liver Disease score and diuretic use at baseline. Renal replacement therapy (RRT) was performed in 19.5% (22 of 113) of patients. The hospital mortality rate in the group with AKI was 25% (16 of 64 patients) and 6.1% (3 of 49 patients) between patients without AKI (odds ratio, 5.11 [confidence interval, 1.39-18.7]; P < .01]. Among patients who underwent RRT, the in-hospital mortality rate was 54.5% (12 of 22 patients) compared with 7.7% (7 of 91 patients) from the other remaining patient cohort (odds ratio, 14.40 [confidence interval, 4.60-45.00]; P < .01).

There was a high incidence of AKI in patients undergoing liver transplantation and an increased risk of mortality among patients who needed RRT.