Indocyanine green clearance reflects reperfusion injury following liver transplantation and is an early predictor of graft function

Background/Aims: Primary graft dysfunction is difficult to predict. We have previously shown that indocyanine green clearance measured at 24 h followi ng orthotopic liver transplantation predicts graft survival and outcome. We prospectively evaluated the use of indocyanine green clearance (with a cut -off value of 200 ml/min) as a marker of graft function following orthotopi c liver transplantation and investigated its relationship with the markers of reperfusion injury during orthotopic liver transplantation. Methods: In all patients indocyanine green clearance was measured at 24 h. Repeated blood samples were taken before, during the anhepatic and reperfus ion phase and up to 12 h following orthotopic liver transplantation to meas ure the levels of neutrophil elastase and reactive oxygen intermediates. Al l patients studied had normal hepatic arterial pulse on Doppler-ultrasound post orthotopic liver transplantation. Results: All patients with indocyanine green clearance >200 ml/min recovere d following orthotopic liver transplantation and remained well up to 3 mont hs of follow up. Four patients had an indocyanine green clearance <200 ml/m in; three were re-transplanted for graft failure within 3 days of the trans plant, while one survived after prolonged intensive support and hospitaliza tion. Indocyanine green clearance significantly correlated with reactive ox ygen intermediates production and neutrophil elastase during orthotopic liv er transplantation (r=-0.61, p<0.002 and r=-0.66, p<0.0009, respectively), Indocyanine green clearance was also significantly correlated,vith alanine aminotransferase and prothrombin time at 24 h post-transplantation (r=-0.35 , p<0.02 and r=-0.4, p<0.0077, respectively). Conclusion: Indocyanine green reflects the degree of reperfusion injury and is a good early marker of primary graft function. Indocyanine green cleara nce over 200 ml/min is associated with favorable outcome.