Adequate Early Graft Function after Orthotopic Liver Transplantation is best predicted by Indocyanine Green Plasma Disappearance Rate

Introduction:The 1- and 5-year survival after orthotopic liver transplantation (OLT) increased the last decade above 85% and 75% respectively. Mortality and morbidity is mainly determined in the early post-operative period1. During this period, monitoring of initial graft function is highly mandatory. Physical examination or conventional laboratory findings, such as serum bilirubin measurements are not accurate predictors of graft and patient survival. However, point-of-care monitoring of the plasma disappearance rate (PDR) of Indocyanine Green dye (PDR-ICG) has been shown to predict early post-operative complications following OLT when measured during the first post-operative days2,3. We evaluated the role of intraoperative PDR-ICG values in the prediction of adequate early graft function after full size adult OLT. Methods:We retrospectively analyzed data from 62 patients undergoing OLT. Early graft function was defined as adequate if there were no signs of primary non-function, hepatic artery or portal vein thrombosis, sepsis, need for surgical re-intervention, acute rejection or early ischemic biliary lesions. PDR-ICG was measured non-invasively by pulse dye densitometry at the end of surgery and was correlated with early graft function. ROC analysis was performed to compare the predictive ability for adequate early graft function of both PDR-ICG and post-operative serum bilirubin measurements.Results:PDR-ICG at the end of surgery was significantly higher in patients with adequate early graft function compared to patients with early post-operative complications (27.2 ± 8.2 %/min versus 23.0 ± 6.9%/min; p<0.05). ROC analysis (fig.1) revealed an area under the curve (AUC) of 0.71 and a cut-off PDR-ICG value for predicting adequate early graft function was determined to be 23.9%/min with a sensitivity of 72.4% and a specificity of 72.7% while serum bilirubin measurement at day 1 and day 7 after transplantation revealed an AUC of 0.54 and 0.69 respectively. A further subgroup analysis could not determine specific complications to be predicted by intra-operative PDR-ICG measurements.Discussion:We demonstrate for the first time that already intraoperative measurement of PDR-ICG during full size adult OLT provides a useful clinical tool that is more sensitive than postoperative measurements of serum bilirubin within the first week to predict adequate early graft function after liver transplantation.References:1. Br J Surg 2010; 97: 744-53.2. Liver Transpl 2009; 15: 1358-64.3. Liver Transpl 2009; 15: 1247-53