Usefulness of Indocyanine Green Plasma Disappearance Rate in Liver Donors and Recipients: A Prospective Observational Study.

BACKGROUND: Determination of indocyanine green (ICG) plasma disappearance rate (PDR) is a simple, inexpensive, and noninvasive tool to assess liver perfusion, absorption, and elimination. Its application in the liver transplant process has not been widely incorporated in clinical practice. This study aims to assess the usefulness of ICG PDR in the donor selection setting and in the early post-transplant phase and to analyze its variation between these 2 time points. METHODS: We performed a single-center prospective observational study. ICG clearance test was performed in 50 brain-dead donors (T0-PDR) to assess concordance with graft suitability. Rejected grafts biopsy specimens were analyzed to correlate histology with T0-PDR. In the recipients, ICG PDR was performed before wound closure (T1-PDR). The association of T0, T1, and T0-T1 variation with the development of early allograft dysfunction (EAD) was investigated. RESULTS: A total of 23 of 50 grafts were discarded because of poor macroscopic quality. A T0-PDR below 15.5%/min could predict graft rejection with 100% specificity and 69.6% sensitivity. All the biopsy specimens from donors with PDR < 10 %/min showed liver fibrosis. A total of 25 of the remaining 27 grafts were implanted; 5 patients (20%) developed EAD. T1-PDR performed better than T0-T1 variation to predict dysfunction. CONCLUSIONS: ICG PDR could be used in the donors as a filter to discard poor-quality grafts before procurement and, in the early post-transplant phase, to predict EAD.

Preconditioning by portal vein embolization modulates hepatic hemodynamics and improves liver function in pigs with extended hepatectomy.

BACKGROUND: Portal vein embolization is performed weeks before extended hepatic resections to increase the future liver remnant and prevent posthepatectomy liver failure. Portal vein embolization performed closer to the operation also could be protective, but worsening of portal hyper-perfusion is a major concern. We determined the hepatic hemodynamic effects of a portal vein embolization performed 24 hours prior to hepatic operation. METHODS: An extended (90%) hepatectomy was performed in swine undergoing (portal vein embolization) or not undergoing (control) a portal vein embolization 24 hours earlier (n = 10/group). Blood tests, hepatic and systemic hemodynamics, hepatic function (plasma disappearance rate of indocyanine green), liver histology, and volumetry (computed tomographic scanning) were assessed before and after the hepatectomy. Hepatocyte proliferating cell nuclear antigen expression and hepatic gene expression also were evaluated. RESULTS: Swine in the control and portal vein embolization groups maintained stable systemic hemodynamics and developed similar increases of portal blood flow (302 ± 72% vs 486 ± 92%, P = .13). Portal pressure drastically increased in Controls (from 9.4 ± 1.3 mm Hg to 20.9 ± 1.4 mm Hg, P < .001), while being markedly attenuated in the portal vein embolization group (from 11.4 ± 1.5 mm Hg to 16.1 ± 1.3 mm Hg, P = .061). The procedure also improved the preservation of the hepatic artery blood flow, liver function, and periportal edema. These effects occurred in the absence of hepatocyte proliferation or hepatic growth and were associated with the induction of the vasoprotective gene Klf2. CONCLUSION: Portal vein embolization preconditioning represents a potential hepato-protective strategy for extended hepatic resections. Further preclinical studies should assess its medium-term effects, including survival. Our study also supports the relevance of hepatic hemodynamics as the main pathogenetic factor of post-hepatectomy liver failure.