Oxygen consumption predicts outcome in porcine partial liver grafts

BackgroundHigh oxygen consumption (OC) in recipients of cadaveric whole liver grafts is associated with a poor prognosis. The aim of this study is to investigate the relationship between intraoperative hepatic OC and graft function and survival in a porcine partial liver graft model.Material and methodsExperiments followed the Guiding Principles in the Care and Use of Laboratory Animals. Fourteen female pigs, 46–69 kg, received liver allografts of 17%–39% liver volume and were followed for 14 d. We measured donor and recipient body weights, percentage graft weight and expressed it as a percentage of standard liver volume, cold ischemia time, hepatic artery flow (HAF), portal vein flow (PVF), graft volume at sacrifice, serum lactate, prothrombin time, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatinine, albumin, total protein, alkaline phosphatase, total bilirubin, and recipient survival. OC was calculated as follows: OC (mL/100 g/min) = ([Hemoglobin {Hb} × 1.34 × SaO2 + 0.003 × PaO2] × HAF + [Hb × 1.34 × SpO2 + 0.003 × PpO2] × PVF − [Hb × 1.34 × SvO2 + 0.003 × PvO2] × [HAF + PVF])/graft weight (100 g), and animals were divided into two groups: low OC group (OC < 2.0 mL/100 g/min) and high OC group (OC ≥ 2.0 mL/100 g/min).ResultsIn survival analysis, four of seven low OC recipients (57% [n = 7]) survived until the end of the study period compared with one of seven high OC recipients (14% [n = 7]). The low OC group had a significantly higher survival rate than that of the high OC group (P = 0.041). Low OC was associated with higher HAF (mL/100 g/min) after reperfusion compared with that of the high OC group, 29.0 ± 13.8 versus 16.0 ± 11.1 mean ± standard deviation; P = 0.073. Serum alkaline phosphatase and total bilirubin in the low OC group were significantly better than those of the high OC group. Serum lactate was comparable in both groups. Graft weight at the time of sacrifice in the low OC group tended to be higher than that in the high OC group, but not significantly (P = 0.097).ConclusionsHigh intraoperative OC is associated with lower HAF, decreased graft function, and decreased survival in the porcine partial liver graft model.