Risk factors for acute kidney injury and 30-day mortality after liver transplantation

Abstract

Introduction: The aim of this study is to evaluate the risk factors for acute kidney injury (AKI) and 30-day mortality after liver transplantation.

Material and methods: This is a retrospective cohort of consecutive adults undergoing orthotopic liver transplantation (OLT) at a referral hospital in Brazil, from January 2013 to January 2014. Risk factors for AKI and death were investigated.

Results: A total 134 patients were included, with median age of 56 years. AKI was found in 46.7% of patients in the first 72 h after OLT. Risk factors for AKI were: viral hepatitis (OR 2.9, 95% CI = 1.2-7), warm ischemia time (OR 1.1, 95% CI = 1.01-1.2) and serum lactate (OR 1.3, 95%CI = 1.02-1.89). The length of intensive care unit (ICU) stay was longer in AKI group: 4 (3-7) days vs. 3 (2-4) days (p = 0.001), as well as overall hospitalization stay: 16 (9-26) days vs. 10 (8- 14) days (p = 0.001). The 30-day mortality was 15%. AKI was an independent risk factor for mortality (OR 4.3, 95% CI = 1.3-14.6). MELD-Na ≥ 22 was a predictor for hemodialysis need (OR 8.4, 95%CI = 1.5-46.5). Chronic kidney disease (CKD) was found in 36 patients (56.2% of AKI patients).

Conclusions: Viral hepatitis, longer warm ischemia time and high levels of serum lactate are risk factors for AKI after OLT. AKI is a risk factor for death and can lead to CKD in a high percentage of patients after OLT. A high MELD-Na score is a predictor for hemodialysis need.