Liver conditioning after cardiac arrest: the use of normothermic recirculation in an experimental animal model.

The aim of this study was to compare the possible role of normothermic recirculation with the role of liver transplants from non-heart-beating donor pigs after 20 min of cardiac arrest. Three groups were studied, of which two were control groups: group 1, in which the liver was harvested from a heart-beating donor; group 2, in which the liver was harvested after a period of cardiac arrest followed by total body cooling; and group 3, in which the liver was procured as in group 2, but including a period of 30 min of cardiopulmonary bypass and tissue oxygenation at 37 degrees C before total body cooling. Survival at 5 days; endothelial (hyaluronic acid) and hepatocellular damage (AST, ALT, and alpha-GST); adenine nucleotides (energy charge), and histological changes were evaluated. Normothermic recirculation during 30 min showed a significant effect on survival (p = .03), endothelial damage (p < .05), and histological changes after reperfusion (p = .04). Cardiopulmonary bypass significantly increased the energy charge during the normothermic recirculation period (p = .001). Moreover, this study shows that a significant survival (100%) can be achieved with a liver allograft after 20 min of cardiac arrest. Although the liver suffers a major insult in terms of endothelial damage and hepatocellular damage, lesions caused by the ischemic injury are reversible. Histological changes also indicate lesion reversibility, since they almost disappear after 5 days.