Background: Transplantation of organs from nonheartbeating donors was recommended to reduce organ shortage. In vitro experiments with rat livers have shown that the warm ischemic tolerance of the liver may be extended by persufflation with gaseous oxygen during cold storage. The qualification of this method for procurement of livers harvested after cardiac arrest was tested in an in vivo approach with pigs.
Methods: Livers from 15 donor pigs were explanted, heparinized, flushed with and stored in University of Wisconsin solution for 4 hr at 4 degrees C, and then implanted into 15 recipients. The organs were dissected immediately after cardiac arrest (group 1) or after 60 min of warm ischemia (groups 2 and 3). Group 2 livers received 75,000 IU of superoxide dismutase together with the flush solution and were persufflated with gaseous oxygen via the venous vascular system during cold storage. Main end point was survival after 5 days. Additionally, metabolic, functional and inflammatory criteria were measured in the blood.
Results: All animals of the groups 1 and 2 survived, all animals of group 3 died within 3 hr after reperfusion. In all groups the blood parameters reflected significant damage of the livers. However, the ischemic damage was comparable in the groups 1 and 2 whereas the livers of group 3 exhibited significantly higher levels of aspartate alanine aminotransferase and lactate dehydrogenase, and a significantly elongated partial thromboplastin time 1 hr after reperfusion (P=0.016).
Conclusions: Venous systemic oxygen persufflation in combination with antioxidative medication is a promising new method of resuscitating ischemically altered livers from nonheartbeating donors for successful transplantation.