Heparin and phentolamine combined, rather than heparin alone, improves hepatic microvascular procurement in a non-heart-beating donor rat-model

Improvement of organ procurement from non-heart-beating donors (NHBDs) coul d increase the donor organ pool for liver transplantation. Whether anti-coa gulative and anti-vasospastic substances can improve hepatic microvascular preservation from NHBDs is unknown. In donor rats which were pretreated wit h either heparin (n = 6) or heparin combined with phentolamine (n = 7) 10 m in prior to cardiac arrest, the extent and homogeneity of hepatic microvasc ular reperfusion was assessed at the end of a 60-min period of cardiac arre st using in situ fluorescence microscopy Non-pretreated animals with cardia c arrest for 60 min served as controls (n = 6). In the non-treated NHBDs, a rterial gravity perfusion of 100 cm H2O with HTK-solution led to a hepatic acinar reperfusion of only similar to 22% with a remarkably diminished sinu soidal density. Application of heparin prior to cardiac arrest resulted in a two-fold, but insignificant increase of acinar perfusion and sinusoidal d ensity with a still considerable heterogeneity of both parameters. Livers o f NHBDs that additionally received phentolamine exhibited significantly inc reased values of both acinar perfusion and sinusoidal density. Phentolamine was found to reduce heterogeneity of organ microperfusion. Thus, our resul ts indicate that the combined application of heparin and phentolamine is a useful additive for optimizing the quality of organs harvested from NHBDs.