TISSUE OXYGEN-SATURATION OF HUMAN HEPATIC GRAFTS AFTER REPERFUSION - PARADOXICAL ELEVATION IN POOR GRAFT FUNCTION

The present study investigated the pathophysiology of primary nonfunct ion (PNF) of grafted livers with regard to hepatic tissue oxygenation. Hemoglobin oxygen saturation in hepatic tissue (H-So(2)) after reperf usion was determined using near-infrared spectroscopy. Graft tissue ox ygen consumption was also estimated according to Fick's principle. Six grafts with PNF were compared with 40 functioning grafts. One PNF gra ft with extremely low and heterogenous H-So(2) after reperfusion was f ound to contain multiple intrahepatic portal thrombi. However, five ot her PNF grafts showed no lower and, on the contrary, more homogeneous H-So(2) at the end of the operation. As a whole, mean H-S2o(2) was neg atively correlated and the coefficient ofvariation (CV) of H-So(2) was positively correlated with graft tissue oxygen consumption at the end of the operation; grafts whose H-So(2) showed a secondary decrease ha d better initial function. In later relaparotomy, the H-So(2) of the f ive PNF grafts was significantly higher and more homogeneous than that of the functioning grafts. These results suggest that the H-So(2) lev el reflects tissue oxygen consumption as well as oxygenation, and that the dissociation of both factors can occur in hepatic graft reperfusi on. Not only low and heterogeneous H-So(2) but also high and homogenou s H-So(2), suggesting some shunt mechanism, can be signs of poor graft function.