Ischaemic preconditioning of the liver before transplantation
Purpose. Assessment of the effect of a short ischaemic time prior to liver transplantation on the liver graft. Methods. White X Landrace pigs (N=10) were subjected to liver transplantation. Before being removed from the donor animal, the livers were randomised into two groups: group 1 – pre-procurement ischaemia (15 minutes\' temporary arrest of portal venous and hepatic arterial inflow to the liver, followed by reperfusion of these vessels for a period of 15 minutes); group 2 – no prior inflow occlusion (control group). In group 1 a spleno-jugular bypass was established to prevent venous congestion, portal venous hypertension, intestinal oedema and bacterial translocation. The livers were perfused with Eurocollins solution (4oC), after which they were stored on ice for a period of 3 hours\' cold ischaemic time. Hepatocellular injury was assessed according to liver cell function tests (aspartate aminotransferase, AST), biochemical indicators of reperfusion injury (malondialdehyde) and histopathology. Results. There was a significant rise of AST in both groups 1 hour after transplantation (from 51±27 IU/l to 357±152 IU/l in group 1 and from 29±10 IU/l to 359±198 IU/l in group 2). AST levels were marginally lower in group 1 at 2 and 4 hours after transplantation. There was also a rise in malondialdehyde levels in both groups at 5, 20, 40 and 60 minutes after transplantation. Levels of malondialdehyde were lower in the primed group at 5, 20 and 40 minutes, while the levels at 60 minutes after transplantation were comparable. Histological changes, as measured by vacuolisation, neutrophil infiltration and hepatic cell necrosis, were less in livers transplanted after ischaemic preconditioning, although the difference was not significant. Conclusions. Ischaemic preconditioning of the donor liver seems to decrease hepatocellular damage, reperfusion injury and histological changes in the liver after transplantation. Further studies with larger numbers are indicated.
South African Journal of Surgery Vol. 45 (4) 2007: pp. 122-127