Histological assessment after different methods of reperfusion following liver transplantation

Preservation-reperfusion injury is a major cause of graft failure after liver transplantation. This injury refers to a variety of insults after reperfusion of the graft, independent of technical errors, vascular problems, immunological reactions or infection. Significant injuries occur during the period of cold preservation. Loss of sinusoidal endothelial attachments to the underlying extracellular matrix results in loss of the normal antithrombogenic milieu. Reperfusion with recipient blood results in platelet aggregation and neutrophil sludging in all areas of denudation, preventing adequate reoxygenation. Early histopathological findings in biopsy specimens can predict poor graft outcome.

To analyse the effect of early rearterialisation on histological findings of the liver biopsies after liver transplantation.

Twenty young Large White X Landrace pigs (weight 22-28 kg) were subjected to orthotopic liver transplantation. Livers were stored in Eurocollins solution for 3 hours on ice and the animals were randomised into four different groups of increasingly early arterialisation. Groups were aligned from delayed rearterialisation (group 1) to early rearterialisation (group 4). Biopsies were taken before and after cold storage, as well as 1 hour post transplantation.

Results show that both hepatocyte vacuolisation and neutrophil infiltration were significantly reduced in group 4 (early rearterialisation), compared with groups 1, 2 and 3. Single cell necrosis and group cell necrosis of the hepatocytes were both significantly reduced in groups 3 and 4 compared with groups 1 and 2 (early venous reperfusion).

This study demonstrates that early rearterialisation is associated with a decrease in early histopathological changes in the transplanted pig liver.