Indocyanine green fluorescence kinetics during hypothermic oxygenated machine perfusion might predict graft function after liver transplantation

BACKGROUND: This study evaluates whether indocyanine green (ICG) fluorescence during hypothermic oxygenated machine perfusion (HOPE) can predict early allograft dysfunction (EAD) after liver transplantation. METHODS: Seventeen donor livers underwent HOPE before transplantation. After one hour, ICG was administered via the portal line. Perfusate samples were collected every five minutes for 50 min; liver tissue and bile samples were obtained during perfusion and after reperfusion. Fluorescence intensity (FI) was quantified using standardized microplate analysis. Associations with donor characteristics and clinical outcomes were analyzed. RESULTS: EAD occurred in 29.4% of recipients and primary non-function in 5.9%. Perfusate FI differed significantly between EAD and non-EAD grafts at 40 and 45 min (p = 0.006; p = 0.05). FI in post-reperfusion liver biopsies was higher in dysfunctional grafts (p = 0.01). Bile fluorescence showed no predictive value. ROC analysis demonstrated strong discrimination for perfusate samples at 40 and 45 min (AUC 0.875; 0.889) and for post-reperfusion tissue (AUC 0.886). Donor variables did not correlate with ICG kinetics. CONCLUSION: In this exploratory pilot study, perfusate fluorescence measurements during HOPE were associated with EAD. These findings suggest that fluorescence- based assessment during machine perfusion may provide functional information on graft quality.