Hyperbaric oxygen therapy reduces the severity of ischaemia, preservation and reperfusion injury in a rat model of liver transplantation

hpb_410 103..114 Background: Approaches to increase organ availability for orthotopic liver transplantation (OLT) often result in the procurement of marginal livers that are more susceptible to ischaemia, preservation and reperfusion injury (IPRI). Methods: The effects of post-OLT hyperbaric oxygen (HBO) therapy on IPRI in a syngeneic rat OLT model were examined at various time-points. The effects of IPRI and HBO on hepatocyte necrosis, apoptosis, proliferation, and sinusoidal morphology and ultrastructure were assessed. Results: Post-OLT HBO therapy significantly reduced the severity of IPRI; both apoptosis (at 12 h: 6.4 0.4% in controls vs. 1.6 0.7% in the HBO treatment group (p < 0.001); at 48 h: 2.4 0.2% in controls vs. 0.4 0.1% in the HBO treatment group (p < 0.001)) and necrosis (at 12 h: 18.7 1.8% in controls vs. 2.4 0.4% in the HBO treatment group (p < 0.001); at 48 h: 8.5 1.3% in controls vs. 3.4 0.9% in the HBO treatment group (P = 0.019)) were decreased. Serum alanine transaminase was reduced (at 12 h: 1068 920 IU/l in controls vs. 370 63 IU/l in the HBO treatment group (P = 0.030); at 48 h: 573 261 IU/l in controls vs. 160 10 IU/l in the HBO treatment group (P = 0.029)). Treatment with HBO also promoted liver regeneration (proliferation at 12 h: 4.5 0.1% in controls vs. 1.0 0.3% in the HBO treatment group (p < 0.001); at 48 h: 8.6 0.7% in controls vs. 2.9 0.2% in the HBO treatment group (p < 0.01)) and improved sinusoidal diameter and microvascular density index. Conclusions: Hyperbaric oxygen therapy has persistent positive effects post-OLT that may potentially transfer into clinical practice.