Metabolic changes in the liver graft monitored continuously with microdialysis during liver transplantation in a pig model

Abstract

Microdialysis provides the opportunity to continuously monitor metabolic changes in tissue. The aim of the study is to monitor metabolic changes in the liver graft over time during transplantation in a pig model. Fourteen littermate female pigs with a body weight of 30 to 34 kg were used for seven orthotopic liver transplantations. Intrahepatic implantation of a microdialysis catheter into the liver graft was performed in the donor. Microdialysis samples were collected at 20-minute intervals during the donor operation, cold preservation, and for 7 hours after reperfusion in the recipient. Glucose, lactate, pyruvate, and glycerol concentrations were measured. After cold perfusion, glucose, lactate, and glycerol levels increased, whereas pyruvate levels decreased rapidly. During cold storage, glucose and glycerol levels increased, whereas lactate levels remained stable and pyruvate levels were undetectable. During implantation of the liver graft, glucose, lactate, and glycerol levels showed an accelerated increase. After portal reperfusion, glucose, lactate, and glycerol levels continued to increase for another 40 to 60 minutes, after which they decreased and finally settled at normal levels. At this time, pyruvate levels increased, with a peak within 2 hours after reperfusion, and then decreased to normal levels. Calculated lactate-pyruvate ratio increased after cold perfusion and remained stable during cold storage. During rewarming, it showed an accelerated increase, but after reperfusion, it decreased rapidly. Rewarming and reperfusion are most harmful to the liver, reflected by an accelerated increase in glucose and glycerol levels and lactate-pyruvate ratio. High intrahepatic glucose levels during ischemia appear to be a liver-specific event, which may represent glycogen degradation in injured hepatocytes. (Liver Transpl 2002;8:424-432.)

Myocardial ischemia-reperfusion and cardioprotection: a study with microdialysis in a porcine model

“…The findings on lactate and pyruvate in study IV indicate that the microdialysate lactate/pyruvate ratio is not a good marker of ischemia during the prevailing circumstances during cold cardioplegic storage. This is supported by two other microdialysis studies of porcine cold hepatic preservation, where the lactate/pyruvate ratio did not perform well as a marker during prolonged storage (Nowak 2002, Puhl 2006.…”

“…The G-3-P may further be hydrolyzed and recovered as glycerol (de Groot 1994). The decrease of pyruvate to undetectable levels during hours of cold storage, observed in study IV, has also been demonstrated for pig livers (Nowak 2002). The findings on lactate and pyruvate in study IV indicate that the microdialysate lactate/pyruvate ratio is not a good marker of ischemia during the prevailing circumstances during cold cardioplegic storage.…”

“…Hypothermia, at 25°C, has been demonstrated to negatively affect the efficacy of the rat skeletal muscle lactate transporters (Roth 1990). In a study of porcine cold hepatic preservation, stable microdialysate lactate concentrations have been demonstrated for up to 15 hours of storage (Nowak 2002). In contrast, when tissue lactate concentrations were analyzed in sequential biopsies from dog hearts during 24 hours of hypothermic storage, continuously increasing levels were demonstrated (Takami 1988).…”

Hemodynamics alterations during orthotopic liver experimental transplantation in pigs

“…Although such technique is attractive, Gruttadauria et al 7 demonstrated that anhepatic phase without venovenous could be easily tolerated during a 30-min period, which is usually sufficient to perform the two venous sutures preceding graft revascularization. Clamping of the supracoeliac aorta produced a significant liver injury compared with the control group 4,5,6,8,13,15,16,17,18,28 .…”

Ischemic preconditioning prior to intermittent Pringle maneuver in liver resections

“…Microdialysis (µD), however, offers the opportunity to clinically follow various local metabolic changes in the liver for several days [16,17].…”