INCIDENCE AND RISK FACTORS FOR EARLY RENAL DYSFUNCTION AFTER LIVER TRANSPLANTATION

INTRODUCTION. Renal dysfunction often occurred after liver transplantation. OBJECTIVES. The aim of the study was to determine its incidence and its risk factors in a clinical series at the University Hospital of Liege, Belgium.
METHODS. Orthotopic liver transplantations performed from January 2006 until Sep- tember 2012 were retrospectively reviewed (n = 187). Patients, with no renal replacement therapy (RRT) before transplantation were classified in four groups according to their highest creatinine plasma level during the first postoperative week. First group had a cre- atinine level below 12 mg/l, the second group between 12 and 20 mg/l, the third group between 20 and 35 mg/l, and the fourth above 35 mg/l. In addition, patients who needed RRT during the first week after transplantation were also classified in the fourth group. Preoperative and perioperative parameters were tested as risk factors: age, sex, body mass index (BMI), length of hospital preoperative stay, prior bacterial infection within one month, preoperative ascites, preoperative treatment with ß-blocker, converting enzyme inhibitor, or non steroidal antiinflammatory drugs, preoperative creatinine and bilirubine level, postop- erative lactate level, need for postoperative vasopressive drugs, surgical revision, mechanical ventilation for more than 24 h, postoperative peaks in bilirubine and transam- inase levels, postoperative hemoglobin level, amount of perioperative blood transfusions, type of immunosuppression. Univariate and multivariate analysis were performed using logistic ordinal regression method.
RESULTS. There were 78 patients in group 1 (41.7 %), 46 in group 2 (24.6 %), 38 in group 3 (20.3 %) and 25 in group 4 (13.4 %). Eighteen patients required RRT: 13 (7 %) during the first week after transplantation (group 4), the 5 others after the first week after transplan- tation (2 in group 1 and 2, and 1 in group 3). There were 7 (3.7 %) early deaths within 28 days after transplantation. Using univariate analysis, the severity of renal dysfunction was correlated with presence of ascites and prior bacterial infection, preoperative bilirubin and creatinine level, need for surgical revision, use of vasopressor, postoperative mechanical ventilation, postoperative bilirubine, transaminase, and hemoglobin levels. The need for transfusion of each type of products also affected renal dysfunction. The ordinal logistic analysis pointed out the BMI (OR = 1.1, p = 0.004), preoperative creatinine level (OR = 11.1, p \ 0.0001), use of vasopressor (OR = 3.31, p = 0.0002), maximal postop- erative bilirubine level (OR = 1.44, p = 0.044) and minimal postoperative hemoglobin level (OR 0.059 p = 0.0005).
CONCLUSIONS. More than half of liver transplanted patients experienced some degree of early renal dysfunction after transplantation. Risk factors are preoperative renal dysfunction, and mainly perioperative circulatory instability requiring the use of vasopressor and post- operative anemia.