RIFLE criteria and hepatic function in the assessment of acute renal failure in liver transplantation.

ABSTRACT

Renal dysfunction in cirrhotic patients is primary related to disturbances of circulatory function, triggered by portal hypertension with chronic intrarenal vasoconstriction and hypoperfusion. Pretransplant renal function is an important factor implicated in the development of acute renal failure (ARF) after liver transplantation (OLT), but other factors mostly related to liver function seem to influence the development of ARF. The Acute Dialysis Quality Initiative workgroup developed the RIFLE classification to define ARF. We sought to evaluate the incidence of ARF among patients undergoing OLT, to evaluate the association of ARF with pre-OLT renal and hepatic functions, and to evaluate the influence of ARF on chronic kidney disease (CKD) at 1 month post-OLT. Clinical, renal, hepatic function, and donor risk index data of 24 patients who underwent deceased donor OLT were collected before transplantation, in the perioperative period and in the first month post-OLT. ARF occurred in 37.5% of patients with 56% developing the R grade and 44% the I grade; no patient showed the F grade. An association was observed between ARF and a higher Model for End-Stage Liver Disease (MELD) score and between ARF and a reduced pre-OLT serum albumin. No association was noted between ARF and other pre-OLT parameters. In cirrhotic patients serum creatinine is a bias for renal function assessment and the Modification of Diet in Renal Disease formula overestimates GFR. Post-OLT CKD was present in 6.7% of patients without ARF and in 44.4% of patients with ARF. The R grade developed more frequently among patients with viral cirrhosis. The association of ARF with MELD and hypoalbuminemia may be the result of a close relationship between renal and hepatic functions among cirrhotic patients. Post-OLT CKD may be the result of unrecognized, preexisting CKD and/or the effects of not fully resolved acute damage to an injured kidney.