Effects of Subnormothermic Perfusion Before Transplantation for Liver Grafts from Donation After Cardiac Death: A Simplified Dripping Perfusion Method in Pigs

Background: Liver transplantation from donors after cardiac death (DCD) provides a solution to the donor shortage. However, DCD liver grafts are associated with a high incidence of primary graft nonfunction. We investigated the effectiveness of subnormothermic porcine liver perfusion, before transplantation from DCD, on graft viability. Methods: Landrace pigs (25–30 kg) were randomly allocated to 3 groups (5 per group): heart-beating (HB) graft, transplanted after a 4-hour period of cold storage (CS); DCD graft, retrieved 20 minutes after apnea-induced cardiac arrest (respiratory withdrawal) and transplanted after a 4-hour period of CS; and subnormothermic ex vivo liver perfusion (SELP) graft, retrieved in the same manner as the DCD graft but perfused with a subnormothermic oxygenated Krebs-Henseleit buffer (21–25°C, 10–15 cm H₂O) for 30 minutes in a simplified dripping manner, without a machine perfusion system, after the 4-hour period of CS, and subsequently transplanted. Results: Although all animals in the HB group survived for >7 days, all animals in the DCD group died within 12 hours after transplantation. In the SELP group, 2 recipients survived for >7 days and another 2 recipients were killed on day 5. The survival rate was significantly better for SELP than for DCD grafts (P =.0016). The values of tumor necrosis factor α were not significantly different between the SELP and HB groups. Preserved structure of the parenchyma was observed in the SELP group on histologic examination. Conclusions: A simplified subnormothermic perfusion before liver transplantation is expected to improve graft viability and survival.