Histidine-tryptophan-ketoglutarate solution versus University of Wisconsin solution in adult-to-adult living donor liver transplantation: A propensity score matching analysis from mainland China.

ABSTRACT: To compare the difference between University of Wisconsin (UW) solution and histidine-tryptophan-ketoglutarate (HTK) solution in adult living donor liver transplantation (LDLT).This study included LDLT patients at the Liver Transplantation Center of West China Hospital of Sichuan University from November 2001 to June 2018. These patients were classified into 2 groups depending on the use of the different preservation solutions, and the confounding factors between the 2 groups were eliminated by propensity score matching. Finally, the incidence of complications; serum examination at postoperative days 1, 3, 5, 7, 14, 21, and 30; and the overall survival rate of the 2 groups were compared to observe whether there were any differences between the 2 preservation solutions.Of the 298 patients we screened, 170 were treated with UW solution and 128 with HTK solution. After propensity score matching, 106 pairs of patients were selected. In the comparison of the 2 groups, the length of intensive care unit stay in the UW group was significantly longer than that in the HTK group (P = .022), but there was no difference in the total length of hospital stay between the 2 groups (P = .277). No statistically significant difference was observed in the 2 groups in terms of the incidence of complications or postoperative examinations. However, the incidence of early allograft dysfunction in the HTK group was slightly lower than that in the UW group (HTK: UW = 14.1%: 20.7%), although the difference was not statistically significant. In terms of the overall survival rate, the 1, 3, and 5-year survival rates of the HTK group were 85.5%, 70.2%, and 65.1%, respectively, while the 1, 3, and 5-year survival rates of the UW group were 83.1%, 67.2%, and 59.8%, respectively, and there was no significant difference between the 2 groups.In conclusion, our study shows that UW solution and HTK solution are equivalent in perioperative safety, the recovery of transplanted liver function, the occurrence of postoperative complications and overall survival and can be safely and effectively applied in adult LDLT. If economic factors are taken into account, HTK can save costs to a certain extent.

The Effect of Histidine-tryptophan-ketoglutarate Solution and University of Wisconsin Solution: An Analysis of the Eurotransplant Registry.

BACKGROUND: Both University of Wisconsin (UW) and histidine-tryptophan-ketoglutarate (HTK) solutions are currently used in the Eurotransplant region for preservation of liver allografts. Previous studies on their effect have led to a lot of discussion. This study aims to compare the effect of HTK and UW on graft survival. METHODS: First liver transplantations in recipients 18 years or older from January 1, 2007, until December 31, 2016, were included. Graft survival was compared for livers preserved with HTK and UW at 30 days, 1, 3, and 5 years. Multivariable analysis of risk factors was performed and outcome was adjusted for important confounders. RESULTS: Of all 10 628 first liver transplantations, 8176 (77%) and 2452 (23%) were performed with livers preserved with HTK and UW, respectively. Kaplan-Meier curves showed significant differences in graft survival between HTK and UW at 30 days (89% vs 93%, P=<0.001), 1 year (75% vs 82%, P=<0.001), 3 years (67% vs 72%, P<0.001), and at 5 years (60% vs 67%, P<0.001). No significant differences in outcome were observed in separate analyses of Germany or non-German countries. In multivariable analysis, UW was associated with a decreased risk of graft loss at 30 days (HR 0.772, P=0.002) and at 1 year (0.847 (0.757-0.947). When adjusted for risk factors, no differences in long term outcome could be detected. CONCLUSIONS: Because the use of preservation fluids is clustered geographically, differences in outcome by preservation fluids are strongly affected by regional differences in donor and recipient characteristics. When adjusted for risk factors, no differences in graft survival exist between transplantations performed with livers preserved with either HTK or UW.

Compared efficacy of preservation solutions on the outcome of liver transplantation: Meta-analysis.

AIM: To compare the effects of the four most commonly used preservation solutions on the outcome of liver transplantations. METHODS: A systematic literature search was performed using MEDLINE, Scopus, EMBASE and the Cochrane Library databases up to January 31st, 2017. The inclusion criteria were comparative, randomized controlled trials (RCTs) for deceased donor liver (DDL) allografts with adult and pediatric donors using the gold standard University of Wisconsin (UW) solution or histidine-tryptophan-ketoglutarate (HTK), Celsior (CS) and Institut Georges Lopez (IGL-1) solutions. Fifteen RCTs (1830 livers) were included; the primary outcomes were primary non-function (PNF) and one-year post-transplant graft survival (OGS-1). RESULTS: All trials were homogenous with respect to donor and recipient characteristics. There was no statistical difference in the incidence of PNF with the use of UW, HTK, CS and IGL-1 (RR = 0.02, 95%CI: 0.01-0.03, P = 0.356). Comparing OGS-1 also failed to reveal any difference between UW, HTK, CS and IGL-1 (RR = 0.80, 95%CI: 0.80-0.80, P = 0.369). Two trials demonstrated higher PNF levels for UW in comparison with the HTK group, and individual studies described higher rates of biliary complications where HTK and CS were used compared to the UW and IGL-1 solutions. However, the meta-analysis of the data did not prove a statistically significant difference: the UW, CS, HTK and IGL-1 solutions were associated with nearly equivalent outcomes. CONCLUSION: Alternative solutions for UW yield the same degree of safety and effectiveness for the preservation of DDLs, but further well-designed clinical trials are warranted.

Liver graft preservation using perfluorocarbon improves the outcomes of simulated donation after cardiac death liver transplantation in rats.

The outcomes of liver transplantation (LT) from donation after cardiac death (DCD) donors remain poor due to severe warm ischemia injury. Perfluorocarbon (PFC) is a novel compound with high oxygen carrying capacity. In the present study, a rat model simulating DCD LT was used, and the impact of improved graft oxygenation provided by PFC addition on liver ischemia/reperfusion injury (IRI) and survival after DCD LT was investigated. Orthotopic liver transplants were performed in male Lewis rats, using DCD liver grafts preserved with cold University of Wisconsin (UW) solution in the control group and preserved with cold oxygenated UW solution with addition of 20% PFC in the PFC group. For experiment I, in a 30-minute donor warm ischemia model, postoperative graft injury was analyzed at 3 and 6 hours after transplantation. For experiment II, in a 50-minute donor warm ischemia model, the postoperative survival was assessed. For experiment I, the levels of serum aspartate aminotransferase, alanine aminotransferase, hyaluronic acid, malondialdehyde, and several inflammatory cytokines were significantly lower in the PFC group. The hepatic expression levels of tumor necrosis factor α and interleukin 6 were significantly lower, and the expression level of heme oxygenase 1 was significantly higher in the PFC group. Histological analysis showed significantly less necrosis and apoptosis in the PFC group. Sinusoidal endothelial cells and microvilli of the bile canaliculi were well preserved in the PFC group. For experiment II, the postoperative survival rate was significantly improved in the PFC group. In conclusion, graft preservation with PFC attenuated liver IRI and improved postoperative survival. This graft preservation protocol might be a new therapeutic option to improve the outcomes of DCD LT. Liver Transplantation 23 1171-1185 2017 AASLD.

Comparable outcome of liver transplantation with histidine-tryptophan-ketoglutarate vs. University of Wisconsin preservation solution: a retrospective observational double-center trial.

BACKGROUND: The question of whether the choice of preservation solution affects outcome after liver transplantation is still not satisfactorily answered. The purpose of this study is to examine the preservation solutions' impact on outcome after liver transplantation. METHODS: A double-center retrospective study of short- and long-term results of 3134 consecutive liver transplantations with follow-up periods up to 23 years was performed applying multivariate, risk-adjusted analyses with a subset for living-donor transplants, pediatric transplants and cases with prolonged cold ischemic times. An additional focus was put on biliary complications. The primary study endpoints were short- and long-term patient survival and death-censored graft survival. Secondary study endpoints were the occurrence of post-transplant complications, the necessity of operative revisions, the length of hospital stay, and the length of intensive care unit stay. RESULTS: Although long-term graft survival appears to be increased by Histidine-Tryptophan-Ketoglutarate-use (p = 0.018), this effect could not be confirmed in risk-adjusted analysis (p = 0.641). Multivariate regression analysis revealed that 3-month mortality (p = 0.120), 3-month graft survival (p = 0.103) and long-term patient survival (p = 0.235) were not influenced by the choice of preservation solution. There was no difference in the occurrence of common complications or necessity of operative revisions after liver transplantation. This was confirmed in subgroup analyses for living donor and pediatric transplantation and cases with prolonged cold ischemic time. Analysis of the preservation solutions' impact on length of hospital (p = 0.113) and intensive care unit stay (p = 0.481) revealed no significant difference. CONCLUSIONS: University of Wisconsin and Histidine-Tryptophan-Ketoglutarate solutions are clinically equivalent. Histidine-Tryptophan-Ketoglutarate solution could have an economically superior profile. The notion that the choice of preservation solution can have an impact on the onset of biliary complications after liver transplantation remains a matter of controversy.

Effect of university of wisconsin and histidine-tryptophan-ketoglutarate preservation solutions on blood potassium levels of patients undergoing living-donor liver transplantation.

BACKGROUND: The potassium content of University of Wisconsin solution (UW) is 125 mEq/L and that of histidine-tryptophan-ketoglutarate solution (HTK) only 9 mEq/L. The aim of the present study was to analyze their effects to change potassium levels on reperfusion among patients undergoing living-donor liver transplantation. METHODS: Anesthesia records of adult living-donor liver transplant patients were reviewed retrospectively. Patients received liver graft preserved in UW were grouped in group I (GI) and HTK in group II (GII). The potassium levels in the anheptic phase were compared with those 5 minutes after reperfusion using paired Student t tests. P values of <.05 were regarded to be significant. RESULTS: Eighty-five GI patients showed the potassium significantly decreased from 3.76±0.70 to 3.60±0.74, whereas the change among 355 GII patients was almost unremarkable: 4.00±0.57 to 3.96±0.06 mEq/L. CONCLUSIONS: Although UW contains a higher potassium content, it seems to have no negative impact on changes in serum potassium levels; in contrast it decreased the potassium level significantly at 5 minutes after reperfusion. Both preservation solutions maintain the patients' potassium levels within the normal range.

Comparative impact on islet isolation and transplant outcome of the preservation solutions Institut Georges Lopez-1, University of Wisconsin, and Celsior.

BACKGROUND: Institut Georges Lopez-1 (IGL-1) is a preservation solution similar to University of Wisconsin (UW) with reversed Na/K contents. In this study, we assessed the impact of IGL-1, UW, and Celsior (CS) solutions on islet isolation and transplant outcome. METHODS: We retrospectively analyzed 376 islet isolations from pancreases flushed and transported with IGL-1 (n=95), UW (n=204), or CS (n=77). We determined isolation outcome and ß-cell function in vitro. Transplanted patients were divided into three groups depending on preservation solution of pancreas, and islet graft function was assessed by decrease in daily insulin needs, C-peptide/glucose ratios, ß-scores, and transplant estimated function at 1- and 6-month follow-up. RESULTS: IGL-1, UW, and CS groups were similar according to donor age, body mass index, and pancreas weight. There was no difference in islet yields between the three groups. Success rates, transplant rates, ß-cell secretory function, and viability were similar for all three groups. We observed no difference in decreased insulin needs, C-peptide glucose ratios, ß-scores, and transplant estimated function at 1- and 6-month follow-up between IGL-1, UW, and CS groups. CONCLUSIONS: Our study shows that IGL-1 is equivalent to UW or CS solutions for pancreas perfusion and cold storage before islet isolation and transplantation.

A novel method of measuring cardiac preservation injury demonstrates University of Wisconsin solution is associated with less ischemic necrosis than Celsior in early cardiac allograft biopsy specimens.

BACKGROUND: No consensus exists on the optimal heart preservative solution (HPS) for cardiac allograft preservation. The significance of varying degrees of acute ischemic necrosis (AIN) in early transplant biopsy specimens is unknown. We investigated the effects of HPS on early cardiac histopathology by developing a novel grading system of AIN. METHODS: A retrospective review of our institutional database of orthotopic heart transplants (OHT) identified hearts preserved with University of Wisconsin (UW) or Celsior solutions. AIN severity was graded on early post-transplant biopsy specimens. Primary stratification was by HPS. Multivariable models examined mortality, AIN grade, primary graft dysfunction (PGD), and right heart failure (RHF). RESULTS: From 1996 to 2010, 42 of 174 adult OHTs were preserved with UW and 132 with Celsior, from which 431 biopsy specimens were reviewed. UW and Celsior had similar 30-day (p = 0.79) and 1-year mortality (p = 0.92). Celsior was associated with significantly more AIN on the first (p = 0.02) and second (p = 0.04) specimens and persisted on multivariable analysis for the first (odds ratio, 2.93; 95% confidence interval, 1.26-6.83; p = 0.01) and second biopsy specimen (2.08; 0.99-4.34; p = 0.05). When stratified by AIN score, 30-day and 1-year mortality were similar (p > 0.05). Adjusted analysis showed increasing AIN score on the first biopsy was strongly associated with an increased incidence of PGD (1.59; 1.02-2.47; p = 0.04) and RHF (2.45; 1.14-5.27; p = 0.02). CONCLUSIONS: Our grading system provides a simple, reproducible method for determining AIN. UW is associated with less AIN than Celsior solution. Early biopsy ischemia is associated with PGD and RHF. AIN may have prognostic significance and its routine evaluation should be considered.

Addition of simvastatin to cold storage solution prevents endothelial dysfunction in explanted rat livers.

UNLABELLED: Pathophysiological alterations in the endothelial phenotype result in endothelial dysfunction. Flow cessation, occurring during organ procurement for transplantation, triggers the endothelial dysfunction characteristic of ischemia/reperfusion injury, partly due to a reduction in the expression of the vasoprotective transcription factor Kruppel-like Factor 2 (KLF2). We aimed at (1) characterizing the effects of flow cessation and cold storage on hepatic endothelial phenotype, and (2) ascertaining if the consequences of cold stasis on the hepatic endothelium can be pharmacologically modulated, improving liver graft function. Expression of KLF2 and its vasoprotective programs was determined in (i) hepatic endothelial cells (HEC) incubated under cold storage conditions with or without the KLF2-inducer simvastatin, and (ii) rat livers not cold stored or preserved in cold University of Wisconsin solution (UWS) supplemented with simvastatin or its vehicle. In addition, upon warm reperfusion hepatic vascular resistance, endothelial function, nitric oxide vasodilator pathway, apoptosis, inflammation, and liver injury were evaluated in not cold stored livers or livers preserved in cold UWS supplemented with simvastatin or vehicle. Expression of KLF2 and its vasoprotective programs decrease in HEC incubated under cold storage conditions. Cold-stored rat livers exhibit a time-dependent decrease in KLF2 and its target genes, liver injury, increased hepatic vascular resistance, and endothelial dysfunction. The addition of simvastatin to the storage solution, maintained KLF2-dependent vasoprotective programs, prevented liver damage, inflammation, and oxidative stress and improved endothelial dysfunction. CONCLUSION: Our results provide a rationale to evaluate the beneficial effects of a vasoprotective preservation solution on human liver procurement for transplantation.

Continuous perfusion of donor hearts with oxygenated blood cardioplegia improves graft function.

Donor hearts cannot be preserved beyond 6h using cold storage (CS). Improving preservation methods may permit prolonged storage of donor heart. We compared graft function in large animal model after prolonged preservation (8h) using continuous perfusion (CP) and CS method. Twenty-four miniature pigs were used as donors and recipients. Donor hearts were either stored in University of Wisconsin solution (UW solution) for 8h at 0-4°C (CS group, n=6) or were continuously perfused with oxygenated blood cardioplegia at 26°C for 8h (CP group, n=6). After preservation, hearts were transplanted into recipients and reperfused for 3h. Left ventricular (LV) function, cardiac output (CO), malondialdehyde (MDA) and adenosine triphosphate (ATP) levels, and water content were measured. Although water content of CP hearts was higher than that of CS, LV contractility and diastolic function of CP hearts were superior to those of CS. In addition, CP hearts performed better than CS hearts on CO in working heart state. ATP was better preserved and MDA levels were lower in CP hearts compared with those of CS (P<0.0001). Donor hearts can be preserved longer using continuous perfusion with oxygenated blood cardioplegia and this method prevents time-dependent ischemic injury.

Liver transplantation using University of Wisconsin or Celsior preserving solutions in the portal vein and Euro-Collins in the aorta.

INTRODUCTION: Orthotopic liver transplantation (OLT) is today the gold standard treatment of the end-stage liver disease. Different solutions are used for graft preservation. Our objective was to compare the results of cadaveric donor OLT, preserved with the University of Wisconsin (UW) or Celsior solutions in the portal vein and Euro-Collins in the aorta. METHODS: We evaluated retrospectively 72 OLT recipients, including 36 with UW solution (group UW) and 36 with Celsior (group CS). Donors were perfused in situ with 1000 mL UW or Celsior in the portal vein of and 3000 mL of Euro-Collins in the aortia and on the back table managed with 500 mL UW or Celsior in the portal vein, 250 mL in the hepatic artery, and 250 mL in the biliary duct. We evaluated the following variables: donor characteristics, recipient features, intraoperative details, reperfusion injury, and steatosis via a biopsy after reperfusion. We noted grafts with primary nonfunction (PNF), initial poor function (IPF), rejection episodes, biliary duct complications, hepatic artery complications, re-OLT, and recipient death in the first year after OLT. RESULTS: The average age was 33.6 years in the UW group versus 41 years in the CS group (P = .048). There was a longer duration of surgery in the UW group (P = .001). The other recipient characteristics, ischemia-reperfusion injury, steatosis, PNF, IPF, rejection, re-OLT, and recipient survival were not different. Stenosis of the biliary duct occured in 3 (8.3%) cases in the UW group and 8 (22.2%) in the CS (P = .19) with hepatic artery thrombosis in 4 (11.1%) CS versus none in the UW group (P = .11). CONCLUSION: Cadaveric donor OLT showed similar results with organs preserved with UW or Celsior in the portal vein and Euro-Collins in the aorta.

Comparative prospective study of two liver graft preservation solutions: University of Wisconsin and Celsior.

University of Wisconsin solution (UWS) is the gold standard for graft preservation. Celsior solution (CS) is a new solution not as yet widely used in liver grafts. The aim of this study was to compare the liver function of transplanted grafts stored in these 2 preservation solutions. The primary endpoints were the rates of primary nonfunction (PNF) and primary dysfunction (PDF). We performed a prospective and pseudorandomized study that included 196 patients (representing 104 and 92 livers preserved in UWS and CS, respectively) at La Fe University Hospital (Valencia, Spain) between March 2003 and May 2005. PNF and PDF rates, liver function laboratory parameters, postoperative bleeding, vascular and biliary complications, and patient and graft survival at 3 years were compared for the 2 groups. The 2 groups were similar in terms of donor variables, recipient variables, and surgical techniques. The PNF rates were 2.2% and 1.9% in the CS and UWS groups, respectively (P = not significant), and the PDF rates were 15.2% and 15.5% in the CS and UWS groups, respectively (P = not significant). There were no significant differences in the laboratory parameters for the 2 groups, except for alanine aminotransferase levels in month 3, which were lower in the CS group (P = 0.01). No significant differences were observed in terms of complications. Three-year patient and graft survival rates were as follows for years 1, 2, and 3: 83%, 80%, and 76% (patient) and 80%, 77%, and 73% (graft) for the UWS group and 83%, 77%, and 70% (patient) and 81%, 73%, and 67% (graft) for the CS group (P = not significant). In conclusion, this study shows that CS is as effective as UWS in liver preservation.

Clinical heart transplantation with extended preservation time (>5 hours): experience with University of Wisconsin solution.

BACKGROUND: Use of University of Wisconsin solution has been suggested for extended organ preservation >4 hours in experimental cardiac transplantation, but few data have been reported from clinical use. This study investigated the impact of preservation with UW solution after prolonged ischemic times on myocardial damage and outcomes after heart transplantation. MATERIALS AND METHODS: Between 1994 and 2006, 34 orthotopic heart transplantations were performed at our institution with cold ischemic times of >or=300 minutes (mean, 325.1 +/- 21.3). Donor organs were perfused with and stored in 1000 mL of University of Wisconsin solution. No significant differences were observed with regard to age, gender, diagnosis, donor inotropic support, and donor-recipient weight ratio when compared with recipients undergoing an ischemic time <300 minutes. RESULTS: After a mean follow-up of 47.6 months (range, 1 day to 147.1 months), Kaplan-Meier survival analysis revealed survivals of 91.0% at 3 months, and 82.9% for the entire observation period. The time required to wean from bypass (mean, 78.1 minutes) was equal when compared with that of recipients experiencing grafts undergoing an ischemic time of <300 minutes, but there was a significantly greater average need for inotropic support over the first 48 posttransplant hours. Neither hospital stay in the ICU (mean, 13.0 days; range, 1-55 days) nor the incidence of acute graft failure or survival was different. CONCLUSION: We conclude that heart preservation with UW limited ischemic damage from prolonged storage and improved myocardial function in the early posttransplant period, thus allowing transplantation of organs with ischemic times >300 minutes.

Conditioning of myocutaneous flaps.

PURPOSE: The improvement of the ischaemic tolerance of myocutaneous flaps is of clinical importance and hence the subject of numerous investigations. METHODS: In an attempt to increase the ischaemic tolerance, 20 myocutaneous flaps (rectus abdominis muscle) in pigs were elevated and perfused with various, established solutions prior to the onset of ischaemia. The flaps were elevated, utilizing the superior epigastric vessels as the pedicle. Ten flaps were flushed with the University of Wisconsin solution, five with the Euro-Collins solution and the last five with a Ringer-Lactate solution, prior to the 6h long, normothermic ischaemia. On the day of operation, the first, third, fifth, seventh and tenth postoperative day clinical examinations and thermography were performed as well as biopsies. Additionally, on the tenth postoperative day, the rate of necrosis was determined morphometrically as the average of three measurements. RESULTS: Ten days after surgery, the flaps pretreated with the University of Wisconsin solution displayed a vital surface area of 89%, the Euro-Collins solution 23% and the Ringer-Lactate solution 14%. Histologically, muscle tissue proved to be more susceptible to ischaemia than skin. CONCLUSION: Regarding the rectus abdominis flap in a pig model, the University of Wisconsin solution proved superior in the prevention of ischaemic injury compared with the Euro-Collins solution and Ringer Lactate. In accordance with the literature, muscle tissue proved to be more susceptible to ischaemia than skin in our study.

The minimal flush volume for washout of preservation fluid in liver transplantation.

OBJECTIVES: Organ preservation is one of the important steps that predicts the patient outcome. However, after revascularization, the high concentration of potassium that influxes into the circulation might cause immediate postreperfusion hyperkalemia. To prevent this complication, the portal vein has been washed out with flush fluid to remove preservation fluid before reperfusion. Up to now, it has not been established what exact amount volume of albumin provides washout of the UW solution. METHODS: Eleven of 20 patients who underwent orthotopic liver transplantation (OLT) between December, 2003, and June, 2005, were enrolled in this study. OLT was performed following the standard technique. Five percent albumin (1000 mL) was flushed through the portal vein canula before reperfusion of the donor liver. Every 100 mL of flush fluid effluent was collected from an incomplete infrahepatic inferior vena cava anastomosis for electrolyte measurement. The 10 flushed fluid samples were measured for potassium concentration. Mean arterial pressure was monitored preoperatively, at 1-minute intervals after reperfusion and at 60 minutes after reperfusion. RESULTS: We observed that 61.5% of potassium was removed after only 100 mL of flush fluid, and 90.8% after 500 mL. Only one patient in this study had an effluent potassium reduction that did not achieved 90% after 500- or 1000-mL flush. However, this patient did not develop either postreperfusion syndrome or hyperkalemia. One patient did experience postreperfusion hyperkalemia (6.20 mEq) with severe hypothermia and cardiac arrest. Five patients had stable hemodynamic profiles and five patients, transient, reversible hypotension without postreperfusion hyperkalemia. DISCUSSION AND CONCLUSIONS: We propose that the minimal flush volume for washout of preservation fluid in liver transplantation is 500 mL, to reduce the risk of postreperfusion syndrome and hyperkalemia.

Comparison of histidine-tryptophan-ketoglutarate solution and University of Wisconsin solution in intestinal and multivisceral transplantation.

BACKGROUND: Previous studies have failed to demonstrate a clinical difference between histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) preservation solutions in clinical transplant outcomes for liver, pancreas, and kidney transplantation. This study compares HTK and UW in bowel transplantation with primary outcomes being graft and patient survival, early graft function, and episodes of rejection. METHODS: Data were extracted using a retrospective chart and medical record review of all bowel transplants between 2003 and 2007, and included both pediatric and adult grafts. Transplanted organs included isolated small bowel, modified multivisceral (bowel, pancreas, and stomach) and multivisceral (bowel, pancreas, stomach, and liver). Immunosuppression included induction with a steroid taper and antithymocyte globulin and anti-CD20 monoclonal antibody (rituximab), followed by maintenance with prograf monotherapy. Bowel surveillance was performed with twice weekly zoom endoscopy and biopsy. RESULTS: There were 54 patients transplanted with 57 grafts, 22 preserved in UW, and 37 in HTK. No differences were noted between the two solutions in initial graft function, appearance of bowel on initial endoscopy, and number of rejection episodes. There were no episodes of pancreatitis in the 44 multivisceral grafts which included a transplant pancreas (14 UW and 30 HTK). Kaplan-Meier survival analysis did not demonstrate a significant difference in graft or patient survival at 30- or 90-days posttransplant. CONCLUSIONS: Intestinal grafts preserved in UW and HTK demonstrate no difference in graft and patient survival at 30- and 90-days posttransplant. There were no differences noted in initial function, endoscopic appearance, rejection episodes, or transplant pancreatitis.

Improvement of canine islet yield by donor pancreas infusion with a p38MAPK inhibitor.

BACKGROUND: The activation of p38 mitogen-activated protein kinases (MAPK) is implicated in cold ischemia-reperfusion injury of donor organs. The islet isolation process, from pancreas procurement through islet collection, may activate p38MAPK leading to cytokine release and islet damage. This damage may be prevented by treating pancreata with a p38MAPK inhibitor (p38IH) before cold preservation. METHODS: Pancreata removed from Beagle dogs were infused with University of Wisconsin solution containing the p38IH, SB203580, and Pefabloc (n=6) or vehicle (dimethyl sulfoxide and Pefabloc) alone (n=7), through the pancreatic duct and preserved using the two-layer method. After 20 to 22 hr, islets were isolated and 3000 IEQ/kg were autotransplanted into the corresponding dog to monitor glucose metabolism. RESULTS: p38IH-treated pancreata yielded significantly more islets than control pancreata (IEQ/g: 2134+/-297 vs. 1477+/-145 IEQ/g or 65,012+/-9385 vs. 45,700+/-5103 IEQ/pancreas; P<0.05). Apoptotic beta-cell percentages assessed by laser scanning cytometry were lower in p38IH-treated than the controls (44%+/-9.4% vs. 61.6%+/-4.8%, P<0.05). Tumor necrosis factor-alpha expression assessed by real-time reverse transcription polymerase chain reaction was significantly lower in the p38IH-treated group than controls. All dogs (3000 IEQ/kg) transplanted with p38IH-treated islets (n=5) became euglycemic versus four of five dogs that received untreated islets. Plasma C-peptide levels after glucagon challenge were higher in animals receiving p38IH-treated islets (n=5) versus untreated islets (n=4) (0.40+/-0.78 vs. 0.21+/-0.05 ng/mL, P<0.05). CONCLUSIONS: Infusion of pancreata with University of Wisconsin solution containing p38IH through the duct before preservation suppresses cytokine release, prevents beta-cell apoptosis, and improves islet yield significantly with no adverse effect on islet function after transplantation. p38IH treatment of human pancreata may improve islet yield for use in clinical transplantation.

Calcium-supplemented University of Wisconsin solution in long-term myocardial preservation.

The purpose of this study was to assess the effects of the addition of calcium to University of Wisconsin solution in long-term myocardial perfusion. In a heterotopic heart transplantation model, performed in pigs, the donor heart was preserved for 24 hours by means of continuous perfusion in this solution, without (24hUW group) or with calcium, 2.4 mmol/L (24hUW+Ca). During this period, the oxygenation and pH of the solution were measured, as were the calcium and lactate concentrations and enzyme release. After two hours of reperfusion, samples were collected from both ventricles for the morphological study. In the control group, there were no signs that reperfusion had triggered the calcium paradox. The addition of this cation to the preservation solution improved the intercellular junction integrity but, at the same time, favored intracellular calcium overload. This is manifested by increased enzyme release during preservation (LDH: 242+/-95 vs 140+/-25; CK: 668+/-371 vs 299+/-83 (U/L). p<0.01 in both cases) and signs of ventricular contracture: hardness and stiffness were significantly more prominent than in the group without calcium supplementation. Moreover, in comparison with the control group, the structural morphology of 24hUW+Ca is characterized by the more prominent and extensive presence of contraction bands and disorganized actin structure. Thus, under the experimental conditions employed in this study, we consider the addition of calcium to Wisconsin solution to be unadvisable.

Microvascular experimental evidence on the relative significance of restoring oxygen carrying capacity vs. blood viscosity in shock resuscitation.

The development of volume replacement fluids for resuscitation in hemorrhagic shock comprises oxygen carrying and non carrying fluids. Non oxygen carrying fluids or plasma expanders are used up to the transfusion trigger, and upon reaching this landmark either blood, and possibly in the near future oxygen carrying blood substitutes, are used. An experimental program in hemorrhagic shock using the hamster chamber window model allowed to compare the relative performance of most fluids proposed for shock resuscitation. This model allows investigating simultaneously the microcirculation and systemic reactions, in the awake condition, in a tissue isolated from the environment. Results from this program show that in general plasma expanders such as Ringer's lactate and dextran 70 kDa do not sufficiently restore blood viscosity upon reaching the transfusion trigger, causing microvascular collapse. This is in part restored by a blood transfusion, independently of the oxygen carrying capacity of red blood cells. These results lead to the proposal that effective blood substitutes must be designed to prevent microvascular collapse, manifested in the decrease of functional capillary density. Achievement of this goal, in combination with the increase of oxygen affinity, significantly postpones the need for a blood transfusion, and lowers the total requirement of restoration of intrinsic oxygen carrying capacity.

Two-layer method (UW solution/perfluorochemical plus O2) for lung preservation in rat lung transplantation.

A new preservation method using perfluorochemicals (PFC) with oxygen administered continuously was developed for lung preservation and compared with traditional cold preservation methods for rat lung transplantation. Male Sprague-Dawley rats underwent orthotopic left lung transplantations of grafts preserved in lactiated Ringers solution (LR), University of Wisconsin solution (UW), Celsior solution, or a two-layer (PFC plus O2) solution for 6 hours. One hour after reperfusion, the right pulmonary artery and bronchus were clamped and 5 minutes later we recorded peak airway pressure and PaO2 level. The isograft was excised for measurement of myeloperoxidase activity, wet-to-dry ratio, and histologic examination to evaluate isograft function. The mean peak airway pressure was 29.80+/-6.72 mm H2O in the LR group, 28.80+/-5.76 mm H2O in the UW group, 33.60+/-5.17 mm H2O in the Celsior group, and 32.40+/-2.60 in the two-layer group. The mean PaO2 level was 99.78+/-76.09 mm Hg in the LR group, 87.84+/-33.58 mm Hg in the UW group, 104.50+/-72.93 mm Hg in the Celsior group, and 62.08+/-31.34 mm Hg in PFC and UW solution plus O2 group (two layers). The mean net myeloperoxidase activity OD level was 0.110+/-0.104 in the LR group, 0.392+/-0.328 in the UW group, 0.351+/-0.620 in the Celsior group, and 0.532+/-0.616 in the two-layer group. The mean wet-to-dry ratio was 7.47+/-1.60 in the LR group, 6.56+/-0.62 in the UW group, 7.54+/-2.19 in the Celsior group, and 5.32+/-2.20 in the two-layer group. The differences between groups in these parameters were not significant. Upon histologic examination, more inflammatory cell aggregates were seen in the two-layer group, less in the LR and the Celsior groups. The function of the lung graft after 6 hours of storage was not better using this two-layer method for preservation than traditional preservation methods in rat lung transplantation. Histologic examination revealed more inflammatory cell aggregates in the lung graft preserved using a two-layer method.