Modified Simple Cold Storage of Rat Livers With Uw Solution

Abstract

Rat livers were preserved with the conventional use of UW solution for 30, 42, and 48 hr and compared with livers in which the vascular bed was expanded with an additional 10 to 60 ml UW/ 100 g liver. The extra UW, expressed as % liver weight, was entrapped during final portal infusion by tying off the supra-and infrahepatic inferior vena cava. A beneficial influence of the vascular expansion was most pronounced in the 40% group, with 10/10, 5/10, and 3/10 long-term survivors following transplantation after 30, 42, and 48 hr preservation versus 3/10 and 0/10 after 30 and 42 hr in the 0% controls. In separate experiments, surrogate indices of preservation quality following reperfusion explained this effect. The 40%-and, to a lesser extent, 20%-livers had higher and more uniformly distributed portal blood flow, better tissue oxygenation, smaller increases in postperfusion liver enzymes, higher adenine nucleotides and energy charge, and less histopathologic evidence of hemorrhage and congestion. Pressure changes in the vena cava fluid sump in additional experiments indicated that retrograde infusion of the trapped UW solution occurred in all of the 10-60% groups during the first 6 hr with stable pressures of 1.5 to 3 cm H 2 0 thereafter. Collectively, these data suggest that the much discussed selective vulnerability of the microvasculature of stored allografts is due in part (or principally) to its selective lack of long-term exposure to the UW solution, which drains out of the open vessels but not from the parenchyma. The potential clinical exploitation of this concept is discussed.Recent literature has emphasized microvascular injury as the principal limitation of static cold liver preservation (1-3). With these methods, the preservation solution does not thoroughly fill the microvasculature and remain there. With the hypothesis that microvasculature collapse during the preservation deprives the vessels of benefit from the preservation fluid and increases the resistance for the reperfusion blood flow, we tested a modification of the standard technique. In our experiment, different amounts of UW solution were infused into preserved rat livers, followed by occlusion of all vessels in order to trap the fluid within the vasculature at all levels. The results after orthotopic transplantation were compared with those using the conventional static preservation technique for various durations. MATERIALS AND METHODS AnimalsMale Lewis rats, weighing 225 to 300 g, were used for donors and recipients, housed in individual cages, and fed ad libitum until the night before the experiment. Operative proceduresOrthotopic rat liver transplantation was performed by the method of Kamada et al., without reconstruction of the hepatic artery (4). Donors were anesthetized by intraperitoneal injection of 50 mg/kg sodium pentobarbital. After ligation of the phrenic veins, the donor liver was NIH Public Access flushed with 5 ml of cold UW solution through a catheter inserted in the abdominal aorta. The organ was then removed, with...

Initial Blood Washout During Organ Procurement Determines Liver Injury and Function After Preservation and Reperfusion

“…As early as in the 1980s an effective blood washout was thought to be mandatory to improve the organ outcome after transplantation (3,18). Procurement studies in man, however, have not been able to demonstrate significant differences in the methods used for initial perfusion.…”

“…Slices were preserved in UW-CSS supplemented with 3 mmol/L fresh glutathione, for a period of 0-, 24-or 48-h cold storage. These time points were chosen based on survival results of rat liver transplantation experiments (13,17,18), revealing that 0-h preservation in UW-CSS resulted in 100% survival, 24 h in 20-50% and 48 h in 0% animal survival. After preservation, 50% of the slices were reperfused, while the other half were immediately analyzed (Table 1).…”

Indocyanine Green Elimination Test in Orthotopic Liver Recipients

“…31 Using a microfil perfusion technique, we have previously shown that microcirculatory damage is augmented after graft reperfusion causing stagnation, pooling, and a filling-defect in the sinusoids, as well as a reduction in hepatic blood flow, particularly in arterial flow. 32 Studies aimed at expanding the microvasculature during liver preservation 33 or modulation of vasoactive substances 34 were shown to improve hepatic blood flow, ICG elimination, and graft function after reperfusion. Further study on the role of hepatic blood flow in the determination of K ICG levels and posttransplant graft function is needed.…”

The effects of vascular bed expansion in steatotic rat liver graft viability

“…In addition, the inherited sinusoidal disturbance in steatotic livers may lead to inadequate perfusion with preservation solution during organ retrieval and subsequent suboptimal protection of the graft throughout the cold storage. In normal rat livers a method of vascular bed expansion (VBE), which was established during prolonged cold storage, was shown to improve subsequent graft reperfusion and function [8]. Apart from the uniform exposure of the entire graft to the UW solution, VBE was thought to prevent sinusoidal collapse by expanding the hepatic microvasculature, which subsequently led to decreased resistance for the reperfusion blood flow [8].…”

“…In normal rat livers a method of vascular bed expansion (VBE), which was established during prolonged cold storage, was shown to improve subsequent graft reperfusion and function [8]. Apart from the uniform exposure of the entire graft to the UW solution, VBE was thought to prevent sinusoidal collapse by expanding the hepatic microvasculature, which subsequently led to decreased resistance for the reperfusion blood flow [8]. We hypothesized that VBE pretreatment in steatotic rat liver grafts would attenuate hepatic injury and improve graft viability and function subsequent to revascularization.…”