UW solution improves duration and quality of clinical liver preservation

Prolonged liver preservation (up to 17 hours) with UW solution had no adverse effect on perioperative blood loss or results of postoperative serum biochemistry studies. After use of this solution, biliary and vascular complications as well as evidence of histologic damage were less. The advantages of the extended preservation time permit liver transplantation to be done as a semi-elective procedure; more patients can be waiting at home instead of near the transplant center. The availability of UW solution also makes it possible to send grafts long distances throughout the nation. Furthermore, surgeons can arrange for backup patients in case the recipient proves to be inoperable. This capability should reduce organ wastage, even before the time limits of preservation with UW solution have been determined definitely. We feel that UW solution undoubtedly has improved both the duration and quality of liver graft preservation.     

HX—3液和UW液保存大鼠肝脏效果的比较

采用大鼠肝脏非循环离体灌注模型比较自制的ＨＸ－３液和ＵＷ液对大鼠肝脏的保存效果。实验结果显示，经ＨＸ－３液原位灌洗并保存４８小时的肝脏肝组织含水量正常，而同等条件下换用ＵＷ液，肝组织的含水量虽无明显变化，但都低于正常值；随着保存时间的延长，两组肝窦内皮细胞死亡率逐渐上升，但在２４小时以内两组肝窥内皮细胞死亡率的差异不显著．     

Successful extended lung preservation with UW solution.

Maximum preservation times of 4-6 hr continue to plague lung transplantation. The high-potassium colloid University of Wisconsin solution (UWS) has proved superior to the crystalloid modified Eurocollins' solution (ECS) for preservation of the liver, kidney, and pancreas. The purpose of this study was to compare UWS and ECS for extended lung preservation using a technique of combined pulmonary and bronchial artery perfusion. Simultaneous pulmonary artery and bronchial artery (via a closed aortic segment) perfusion was employed to harvest the lungs of ten mongrel dogs (wt 25-35 kg) using either UWS (n = 5) or ECS (n = 5) preservation solutions. Following 17 hr of cold (4 degrees C) pulmoplegic storage, the lungs were placed in an isolated perfused working lung (IPWL) apparatus. Seven freshly harvested lungs served as a control group (CON). Lung aerodynamics and gas exchange were evaluated at standard intervals until failure of the lung on the IPWL apparatus. Time until failure (mean +/- SEM) for each group was: CON = 209 +/- 14 min; UWS = 227 +/- 26 min; and ECS = 123 +/- 29 min. Only one of the ECS lungs lasted longer than 90 min. UWS-preserved lungs displayed a gas exchange efficiency equal to the CON group and better than that in the ECS-preserved lungs (lower A-aDO2, lower intrapulmonary shunt), suggesting better protection of the alveolar capillary membrane. Although the UWS lungs were initially less compliant than the ECS lungs, at no time was there a significant difference in the total work of respiration between the two groups. We conclude that UWS provides superior protection of the alveolar capillary membrane. The aerodynamic disadvantages of UWS preservation did not effect lung survival or total work of respiration.     

Twenty-four-hour canine lung preservation using UW solution

The left lungs of 14 mongrel dogs were isolated, preserved, and then reperfused for 120 min. Three groups of lungs were investigated: group 1, nonpreserved lungs (control n = 5); group 2, lungs were flushed with UW solution and cold-stored (4-6 degrees C) in the same flush solution for 24 hr (n = 4); and group 3, lungs flushed and cold-stored with modified Euro-Collins' solution for 24 hr (n = 5). Airway pressure (AWP), static lung compliance (Cst), and pulmonary vascular resistance (PVR) 120 min after reperfusion were significantly higher in group 3 compared with the lungs in group 1 and group 2. AWP was 18.7 +/- 3.9 in group 1, 21.1 +/- 3.8 in group 2, and 33.8 +/- 9.2 ml/cmH2O (mean +/- SD) in group 3 (P less than 0.05). Cst was 14.0 +/- 3.5, 10.8 +/- 1.5, and 6.2 +/- 1.2 ml/cmH2O, respectively (P less than 0.01). Pulmonary vascular resistance was 125 +/- 16, 120 +/- 42, and 410 +/- 108 mmHg/L/min (P less than 0.05). We conclude that UW solution is useful for hypothermic canine lung preservation.     

Superior myocardial preservation with modified UW solution after prolonged ischemia in the rat heart

Cardiac transplantation remains constrained by poor graft tolerance of prolonged cold ischemia. University of Wisconsin solution has remarkably extended ischemic preservation in pancreas, kidney, and liver transplantation. To assess its efficacy in cardiac preservation, modified University of Wisconsin solution flush and storage were tested against St. Thomas' cardioplegia flush and normal saline solution storage after six hours of ischemia at 0 degrees C in 46 isolated rat hearts. After ischemia, groups were compared before and after reperfusion. After ischemia but before reperfusion, University of Wisconsin solution hearts had significantly less tissue water (3.8%), superior tissue sodium, potassium, calcium, and magnesium profiles, and elevated adenosine and inosine levels, and tended toward better histological preservation. After reperfusion, University of Wisconsin solution more effectively preserved left ventricular compliance (75% versus 35% of baseline), developed pressure (71% versus 45% of baseline), histological integrity, and tissue potassium and calcium profiles than St. Thomas' solution. The University of Wisconsin solution provided superior preservation of systolic and diastolic ventricular function, tissue histology, tissue water, and tissue electrolytes than did St. Thomas' cardioplegia and normal saline solution storage in this experimental model, and might result in improved graft tolerance of ischemia in clinical cardiac transplantation.     

24-hour rat liver preservation using UW solution and some simplified variants

The results of a series of 32 rat liver transplants are described to analyze the efficacy of components of UW solution. Rat livers were stored at 4 degrees C in standard UW solution or one of three simplified variants for 24 hr prior to orthotopic liver transplantation. In standard UW solution (solution A) the one-week survival rate was 3 of 8. Using solution B, which differs from solution A in the omission of hydroxyethyl starch and adenosine, the one-week survival rate was 2 of 8. Solution C, a further-simplified version of solution B with omission of allopurinol, Bactrim, and insulin, gave a one-week survival rate of 3 of 8. Solution D is identical to solution B except that the sodium and potassium concentrations are reversed. Using this solution, 5 of 8 rats survived more than one week. We conclude that the effectiveness of UW solution is maintained in a substantially simplified form, and that solution D, with the Na/K ratio reversed to give a high Na variant, may improve survival.     

Donor allopurinol treatment improves organ preservation of the kidney also when using UW solution]

Kidney function following hypothermic preservation with Eurocollins (EC) was previously shown to be improved by donor treatment with Allopurinol (AP) [1]. The University of Wisconsin organ preservation solution (UW), however, contains Allopurinol (1 mM). A syngeneic rat kidney transplant model was used to investigate concurrent Allopurinol donor-pretreatment (40 mg/kg b.w.). Kidney graft function resulted to be improved by AP pretreatment following organ preservation with both EC or UW as evidenced by significant reduction in serum creatinine values. On day two following transplantation the respective serum creatinine values (mumol/l) with and without AP-pretreatment were 424 +/- 39 and 662 +/- 25 for EC, and 259 +/- 48 and 387 +/- 48 for UW organ preservation. Furthermore survival- and histology-data were also superior for recipients of kidney grafts from AP-pretreated donors. We conclude that Allopurinol concentration in the UW solution might be to low or that adding AP into an organ storage solution is not the best application modality.     

Molecular damage to rat liver mitochondrial H(+)-ATPase during cold preservation with UW solution.

Deterioration of rat liver mitochondrial function during cold preservation with UW solution was studied. Mitochondria were isolated from control liver (0-hr preservation), 24-hr preserved liver, and 48-hr preserved liver with UW solution at 4 degrees C. Respiration assay revealed that phosphorylation was damaged more rapidly than oxidation. Inside-out submitochondrial particles prepared from each sample by sonication in the presence of EDTA were subjected to ATPase assay. ATP hydrolyzing activity of H(+)-ATPase (ATP synthase), which plays a key role in phosphorylation in mitochondria, decreased markedly to 58% after 24-hr preservation. After 48-hr preservation, reduction to 40% of control was noted. When an intrinsic H(+)-ATPase inhibitor protein was removed from ESMP by Sephadex gel filtration, decrease of the ATPase activity was enhanced down to 49% and 29% of the control for 24-hr and 48-hr preserved liver, respectively. Molecular damage of the enzyme was confirmed by SDS-PAGE. Alpha subunit of the enzyme decreased time-dependently, and H(+)-ATPase molecules that lost alpha subunit seemed to lose their catalytic activity. Although the cause of the molecular damage of H(+)-ATPase is not clear yet, some mitochondrial protease(s) may be involved.     

A comparison of a new solution combining histidine and lactobionate with UW solution and eurocollins for rat liver preservation

Forty-six rat liver transplants were performed to investigate the effectiveness of a simplified lactobionate solution containing histidine as a buffer (histidine-lactobionate solution) and to compare it with University of Wisconsin solution. This new solution is isoosmotic (320 mOsm/L) and has a higher sodium content and a lower potassium content (Na: 90 mEq/L, K: 45 mEq/L) than standard UW solution. Buffering capacity is increased by adding histidine (90 mM/L) together with KH2PO4 (20 mM/L) and is greater than that of Eurocollins solution or UW solution. Adenosine, insulin, hydroxyethyl starch, and dexamethasone that are included in UW solution are not included in the new solution. The 1-week survival rate of rats transplanted with livers preserved in this solutions at 4 degrees C was 85% (11/13) following 24-hr preservation and 33% (2/6) after 30-hr preservation. By contrast, UW solution gave only a 29% (5/17) survival rate after 24-hr preservation and 0% (0/6) survival after 30-hr preservation, demonstrating that this simplified UW solution with histidine is superior to UW solution in rat liver preservation. No rats (0/4) receiving livers preserved for 24 hr in Eurocollins solution survived. These findings show that the inclusion of histidine as a buffer dramatically improves the effectiveness of lactobionate-based preservation solutions and justify application in a large-animal model and subsequently in clinical liver transplantation.     

A comparison of UW with Eurocollins preservation solution in liver transplantation

Fifty consecutive liver transplants were performed using livers perfused with and stored in University of Wisconsin preservation solution. These grafts were compared with the preceding 55 consecutive transplants performed using livers perfused and preserved with Eurocollins solution. The purpose of the study was to determine if organs preserved with UW solution functioned better after transplantation than organs preserved with Eurocollins. Extensive retrospective analysis of prospectively accumulated data included enzyme levels through 30 days, cost and length of hospital stay, blood product usage, and ischemia time. Average age of patients in the UW group was 47.1 years compared with 39.6 years in the EC group (P less than 0.05); cold ischemia time was 7.21 hr in the UW group compared with 5.21 in EC (P = 0.0001). Total bilirubin values were significantly lower on days 0-6 and day 14, but not day 30, in the UW group. Aspartate aminotransferase was significantly lower in the UW group on days 0-1, 3-6, and 14, but not on day 3 or day 30. Prothrombin times were significantly lower in the UW group across all times (days 0-6, 14, and 30). Intraoperative and postoperative use of packed red blood cells and fresh frozen plasma was lower in the UW group (P less than or equal to .05). Also, total hospital days, intensive care unit days, and hospital cost to the patient were lower in the UW group (P less than or equal to .05). A second analysis was done comparing only nonemergent transplants from both groups. These results confirmed the initial analysis of a longer cold ischemia time in the UW group (P less than 0.001), and improved enzyme values in the TBR, AST, and PT in the UW group (P less than 0.05). Also, hospital cost in the UW group was again lower (P less than 0.05). In this nonrandomized study, the cold ischemia time was increased but kept close to that of the control group. We conclude that UW solution is an improved donor liver preservation solution on the basis of improved enzyme values, decreased blood usage, shorter hospital stay, and lower hospital charges.     

Evaluation of UW solution for preservation of small intestinal transplants in the rat.

Simple cold preservation was evaluated in the rat model of small intestinal transplantation. Lewis rats received a syngeneic heterotopic graft of the jejunum either immediately (SI) or after preservation for 24 hr in Euro-Collins (SPE24), for 48 hr in EC (SPE48), for 24 hr in University Wisconsin solution (SPW24), or for 48 hr in UW (SPW48). The survival rates of SI, SPE24, SPE48, SPW24, and SPW48 were 100%, 78%, 0%, 100%, and 33%, respectively. Physiologic and pharmacologic properties of the grafts and native intestine were evaluated in vitro between 8 and 12 days after transplantation. Smooth muscle in all specimens contracted in response to cholinergic agonists, phenylephrine, and substance P, and was relaxed by isoproterenol. Excitatory innervation was present in 100%, 100%, 100%, and 67% of SI, SPE24, SPW24, and SPW48, respectively, while inhibitory innervation in each group was 50%, 29%, 60%, and 0%. Thus, smooth muscle function was preserved in all groups, but neural activity was impaired by some of the storage conditions. Preservation was best in SPW24, which had physiologic responses similar to those of SI. The rat jejunum can, therefore, be preserved in good condition for up to 24 hr before transplantation using simple cold storage in UW solution.     

新型器官保存液低温保存猪肾效果的研究

目的研究新型器官保存液Lifor液对猪肾脏的低温保存效果。方法 24只白色杂种猪,随机均分为Lifor液保存组和威斯康星大学保存液（UW液）组各12只,建立离体肾脏非循环灌注模型,供肾取出后分别以0~4℃的Lifor液和UW液灌注并低温保存,再根据保存时间随机分成2个亚组,分别为保存24h、48h组,然后行猪自体肾移植。比较两组肾脏低温保存结束后其病理学及肾皮质三磷腺苷（ATP）含量的改变,并观察自体肾移植后肾功能恢复情况。结果供肾离体保存24h、48h后,Lifor液组与UW液组的肾组织病理学改变基本一致,肾皮质ATP含量比较差异无统计学意义（P〉0.05）。移植后两组血清肌酐水平比较差异亦无统计学意义（P〉0.05）。结论 Lifor液低温保存肾脏的效果与UW液相当,且成本低廉,因此更具有临床应用前景。     

A comparison of some simplified lactobionate preservation solutions with standard UW solution and Eurocollins solution for pancreas preservation.

Fifty-two rat pancreas transplants were performed to investigate which components of the UW solution were essential for successful pancreas preservation. LEW rats were used and the pancreata stored at 4 degrees C for 48 hr after flushing with commercial UW solution (ViaSpan, DuPont Pharmaceuticals) or a number of simplified solutions. Following storage the pancreata were transplanted into syngeneic recipient animals with streptozotocin-induced diabetes mellitus. Graft function was assessed by regular postoperative blood sugar measurements and a glucose tolerance test on the 14th postoperative day. With commercial UW solution, 4 of 9 recipients (44%) showed satisfactory graft function, while only one of 5 pancreata preserved using Eurocollins solution demonstrated satisfactory function. With solution A, in which hydroxyethyl starch and insulin were omitted from the standard UW solution, 3 of 7 recipients (43%) showed satisfactory function. Omission of glutathione, allopurinol, and adenosine from this solution (solution B) gave satisfactory function in 4 of 8 cases (50%). Substitution of raffinose in solution B with an equimolar concentration of glucose (solution C) resulted in acceptable function in 5 of 8 cases (62%). Increasing the raffinose concentration in solution B to 100 mM/L resulted in only 2 of 8 grafts (25%) with adequate function. By contrast, reversing the Na/K concentrations in solution A resulted in 100% (7/7) satisfactory graft function. We conclude that the rat pancreas can be successfully transplanted following 48-hr cold preservation using UW solution and some simplified versions, and that a substantially simplified lactobionate-based solution with a reversed sodium/potassium ratio improved survival.