Impact of organ preservation using HTK for graft flush and subsequent storage in UW in rat kidney transplantation

BACKGROUND: In kidney transplantation, preservation has a significant influence on organ function. Since previous reports have indicated a benefit of combining histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) solution, we evaluated the effects of initial flush with low viscosity HTK, followed by storage in UW. MATERIAL AND METHODS: Kidneys from inbred Lewis rats were procured using HTK or UW for initially perfusion and re-flushed after 30 min with either solution. In a third group, after perfusion with HTK, organs were re-flushed with UW. Organs were stored for 16-24 h (4 degrees C). Study parameters were high-energy phosphates, histology, apoptosis, recipient survival and urine excretion of 15-F2t -isoprostanes (oxidative stress marker). RESULTS: Prior to transplantation, tissue ATP/ADP concentrations were: HTK/UW > UW-only > HTK-only. In transplanted kidneys, histological damage was highest after preservation in HTK-only. Twenty-four hours after transplantation (24 h cold ischemia time - CIT), cleaved-PARP was most abundant using UW-only. 16 h of CIT resulted in higher urine concentrations of isoprostanes in the order HTK-only (368 +/- 308) > UW-only (157 +/- 105) > HTK/UW (67 +/- 26), and was lower in HTK/UW after 24 h of CIT (146 +/- 38) vs. UW-only (507 +/- 33 pg/mg creatinine). Survival (24 h CIT) was significantly reduced, and percentage of initial non-functioning (INF) kidneys highest in HTK-only (2.6 +/- 0.3 days, 100%), compared to UW-only (13 +/- 4.4 days, 75%) and HTK/UW (18.5 +/- 4.6 days, 33%). CONCLUSIONS: In long-term preservation, UW is superior over HTK. However, our results indicate that perfusion with HTK prior to storage in UW may improve the results of UW alone which is reflected by better survival, lower rate of INF, higher cellular energy conservation and a decrease of free radicals.     

A prospective randomized multicenter trial comparing histidine–tryptophane–ketoglutarate versus University of Wisconsin perfusion solution in clinical pancreas transplantation

We aimed to evaluate early pancreas transplant graft function after histidine–tryptophan–ketoglutarate (HTK) versus University of Wisconsin (UW) perfusion. Prospective randomized multicenter study including 68 pancreas transplantations stratified according to preservation fluid used (27 HTK vs. 41 UW). Primary endpoint was pancreas graft survival at 6 months. Serum α-amylase, lipase, C-peptide, HbA1C and exogenous insulin requirement were compared at several time points. Mean pancreas cold ischemia time was 10.8 ± 3.7 (HTK) vs. 11.8 ± 3.4 h (UW) ( P  = 0.247). Simultaneous pancreas–kidney transplantation was performed in 95.6% of the patients, pancreas transplantation alone in 2.9%, and pancreas after kidney transplantation in 1.5%. Six months graft survival was 85.2% (HTK) vs. 90.2% (UW) ( P  = 0.703). Serum amylase and lipase values did not differ between both the groups during the observation period. C-peptide levels were elevated in both the groups without significant differences at each time point. Higher exogenous insulin requirement early after transplantation in the UW group had resolved at 3 months. Six month patient survival was 96.3% (HTK) vs. 100% (UW) ( P  = 0.397). With a mean cold ischemia time of 10 h in this study, HTK and UW solutions appear to be equally suitable for perfusion and organ preservation in clinical pancreas transplantation.     

Long-term outcomes after 1000 heart transplantations in six different eras of innovation in a single center

The objective of this study was to evaluate long-term outcomes of cardiac transplantation (HTx) in different eras of innovation at a single center during a period of 27 years. We performed a retrospective analysis of 960 cardiac allograft recipients (40 re-HTx) between 1981 and 2008. The results of six different eras based on milestones in HTx were analysed: Era 1: the early years ( n  = 222, 1981–1992); era 2: introduction of inhalative nitric oxide, prostanoids, University of Wisconsin solution (UW) replacing Bretschneider's solution (HTK, n  = 118, 1992–1994); era 3: statins ( n  = 102, 1994–1995); era 4: tacrolimus ( n  = 115, 1995–1996); era 5: mycophenolate mofetil (MMF, n  = 143, 1997–2000) and era 6: sirolimus ( n  = 300, 2000–2008). Outcome variables were survival, freedom from cardiac allograft vasculopathy (CAV) and from acute rejection episodes (AREs). Differences in survival was found comparing era 1 and era 2 with era 4 and era 6 ( P  < 0.001). Organ preservation through UW demonstrated a significantly better survival as compared with HTK ( P  < 0.001). Less AREs occurred in patients receiving tacrolimus-sirolimus or tacrolimus-MMF ( P  < 0.001). Patients receiving tacrolimus-MMF showed less CAV than when treated with cyclosporine-MMF ( P  < 0.005). There were more ventricular assist device implantations and more re-HTx in era 6 ( P  < 0.0001) than when compared with other eras. Although the causes for improvement in survival over time are multifactorial, we believe that changes in immunosuppressive therapy have had a major impact on survival.     

Kidney transplantation from non-heart-beating donors after oxygenated low-flow machine perfusion preservation with histidine–tryptophan–ketoglutarate solution

The aim of this study was to determine the potential benefit of aerobic machine preservation (MP) with non-colloidal histidine–tryptophan–ketoglutarate (HTK) solution compared with MP with Belzer machine perfusion solution (MPS) and standard cold storage, after marginal kidneys had been obtained from non-heart-beating donors. Cardiac arrest was electrically induced in anaesthetized German landrace pigs (20–25 kg bw). Their kidneys were harvested 40 min thereafter, flushed with HTK by gravity of 100 cm H₂O via the renal artery and then stored in HTK for 18 h at 4°C. Other organs were subjected to oxygenated (pO₂>500 mmHg) hypothermic pulsatile low-flow machine perfusion with HTK or MP with Belzer MPS at P_max=40 mmHg, yielding transrenal flow values of 0.2–0.3 ml/min per g with HTK and approximately twice that amount with Belzer MPS. A well-preserved vascular endothelium and intact tubular epithelium were documented by electron microscopy at the end of perfusion preservation in both solutions as well as after cold storage. Concentrations of ATP (in micromoles per gramme) in tissue homogenates at the end of perfusion preservation with HTK were 1.18±0.12 vs 0.16±0.02 (P<0.05) after simple cold storage and 2.43±0.23 after perfusion with Belzer MPS, thus documenting a relevant effect of low-flow perfusion on tissue oxygenation. Viability of the grafts was followed for 1 week after heterotopic transplantation and bilateral nephrectomy in the recipient pigs. Machine perfusion with HTK significantly improved cortical microcirculation upon early reperfusion in vivo, as well as maximal serum levels of urea and creatinine, compared to recipients receiving cold-stored grafts. No differences could be found between MP with HTK or Belzer MPS. In conclusion, provision of oxygen during storage is possible by low-flow perfusion with HTK as with Belzer MPS and apparently improves graft viability after transplantation.     

Dual aortic and portal perfusion at procurement prevents ischaemic‐type biliary lesions in liver transplantation when using octogenarian donors: a retrospective cohort study

Several risk factors for ischaemic‐type biliary lesions (ITBL) after liver transplantation (LT) have been identified, but the role of portal vein perfusion at graft procurement is still unclear. This was a prospective study on double aortic and portal perfusion (DP) of liver grafts stratified by donor's decade (<60 yo; 60–69 yo; 70–79 yo and ≥80 yo) versus similar historical cohorts of primary, adult grafts procured with single aortic perfusion (SP) only. The primary study aim was to assess the role of DP on the incidence of ITBL. There was no difference in the incidence of overall biliary complications according to procurement technique for recipients of grafts <80 years. A higher incidence of ITBL was observed for patients receiving grafts ≥80 years and perfused through the aorta only (1.9 vs. 13.4%; P = 0.008). When analysing octogenarian grafts, donor male gender (HR = 6.4; P = 0.001), haemodynamic instability (HR = 4.9; P = 0.008), and type‐2 diabetes mellitus (DM2) (HR = 3.0; P = 0.03) were all independent risk factors for ITBL, while double perfusion at procurement (HR = 0.1; P = 0.04) and longer donor intensive care unit (ICU) stay (HR = 0.7; P = 0.04) were protective factors. Dual aortic and portal perfusion has the potential to reduce post‐transplant ITBL incidence for recipients of octogenarian donor grafts. Larger series are needed to confirm this preliminary experience.     

Experience with hystidine tryptophan ketoglutarate versus University Wisconsin preservation solutions in transplantation

We present our experience with histidine tryptophan ketoglutarate (HTK) and University Wisconsin (UW) preservation solutions in liver transplantation and a review of the literature in pancreas and kidney transplantation comparing these solutions. A group of 134 liver transplantations in 123 recipients was analyzed retrospectively. Grafts procured in adults were perfused with HTK in 63 cases and with UW in 71 cases. We compared results according to preoperative, intraoperative, and postoperative parameters, as well as complications and survival. No differences regarding donor and recipient data, intraoperative fresh frozen plasma (FFP) substitution, length of intensive care unit (ICU) stay, and ischemic damage of the graft were found. The rate of complications was comparable in both groups. However, the bilirubin was higher in the UW group. The rate of biliary complications was higher in the UW group (n = 8) versus the HTK group (n = 5). HTK ischemic type biliary lesions (ITBL) were only present in the UW group. Patient and graft survival were statistically nonsignificant. The data confirm that HTK and UW, with exception of biliary complications, are considered comparable in clinical liver transplantation. The same conclusion can be taken from the literature analyzed concerning renal transplantation, and in smaller groups of pancreas transplants, similar results were published.     

Kidney transplantation from non-heart-beating donors after oxygenated low-flow machine per fusion preservation with histidine-tryptophan-ketoglutarate solution

Abstract The aim of this study was to determine the potential benefit of aerobic machine preservation (MP) with non‐colloidal histidine‐tryptophan‐ketoglutarate (HTK) solution compared with MP with Belzer machine perfusion solution (MPS) and standard cold storage, after marginal kidneys had been obtained from non‐heart‐beating donors. Cardiac arrest was electrically induced in anaesthetized German landrace pigs (20–25 kg bw). Their kidneys were harvested 40 min thereafter, flushed with HTK by gravity of 100 cm H₂O via the renal artery and then stored in HTK for 18 h at 4°C. Other organs were subjected to oxygenated (pO2 > 500 mmHg) hypothermic pulsatile low‐flow machine perfusion with HTK or MP with Belzer MPS at Pmax = 40 mmHg, yielding trans‐renal flow values of 0.2–0.3 ml/min per g with HTK and approximately twice that amount with Belzer MPS. A well‐preserved vascular endothe‐lium and intact tubular epithelium were documented by electron microscopy at the end of perfusion preservation in both solutions as well as after cold storage. Concentrations of ATP (in micromoles per gramme) in tissue homogenates at the end of perfusion preservation with HTK were 1.18±0.12 vs 0.16 ± 0.02 (P>0.05) after simple cold storage and 2.43 ±0.23 after perfusion with Belzer MPS, thus documenting a relevant effect of low‐flow perfusion on tissue oxygenation. Viability of the grafts was followed for 1 week after heterotopic transplantation and bilateral ne‐phrectomy in the recipient pigs. Machine perfusion with HTK significantly improved cortical micro‐circulation upon early reperfusion in vivo, as well as maximal serum levels of urea and creatinine, compared to recipients receiving cold‐stored grafts. No differences could be found between MP with HTK or Belzer MPS. In conclusion, provision of oxygen during storage is possible by low‐flow perfusion with HTK as with Belzer MPS and apparently improves graft viability after transplantation.     

Comparison of histidine-tryptophan ketoglutarate and University of Wisconsin solutions as primary preservation in renal allografts undergoing pulsatile perfusion

INTRODUCTION: University of Wisconsin (UW) solution is the standard preservation solution for organ transplantation. Histidine-tryptophan ketogluatarate (HTK) solution has been used increasingly for kidney, pancreas, and liver transplantation. This study compared HTK and UW used during kidney procurement with subsequent pulsatile perfusion. METHODS: Between January and October 2003, 91 deceased renal and simultaneous kidney pancreas transplants were performed (UW, n = 41, and HTK, n = 50). There were no differences with regard to donor and recipient demographics or cold ischemia. RESULTS: Delayed graft function occurred in 3 (7%) of UW and 4 (8%) of HTK-preserved kidneys (P = NS). There were no significant differences between patient or graft survival. There was an anticipated difference between total preservative volumes used (HTK: 4.1 +/- 1.0 vs UW: 3.0 +/- 0.5; P < .005). CONCLUSION: UW and HTK appear to have similar efficacy in kidney preservation with pulsatile perfusion. HTK preservation solution can be used safely in conjunction with pulsatile preservation for cold storage of renal allografts.     

Oxygenated machine perfusion preservation of predamaged kidneys with HTK and Belzer machine perfusion solution: an experimental study in pigs

The objective of the present study was to evaluate the recently proposed aerobic machine preservation with the noncolloidal HTK solution by comparison with the colloidal Belzer machine perfusion solution (MPS) after procurement of marginal kidneys from non-heart-beating donors. Kidneys were harvested 40 minutes after cardiac arrest in German Landrace pigs and subjected to 18 hours of oxygenated hypothermic machine perfusion with either Belzer MPS or modified HTK via the renal artery (Psys < 40 mm Hg). During machine perfusion transrenal flow was approximatively twofold higher and calculated oxygen uptake was increased by 30% using the colloidal Belzer MPS, but overall enzyme release was comparable in both groups. After heterotopic transpantation with bilateral nephrectomy of the recipient, there were no differences with respect to initial tissue perfusion in vivo (evaluated by laser Doppler flowmetry) as well as urine production and median serum levels of urea or creatinine over 1 week of follow-up between grafts perfused with HTK or Belzer MPS. In conclusion, provision of oxygen during storage is possible by low-flow perfusion with HTK as with Belzer MPS.     

Comparison of histidine-tryptophan-ketoglutarate solution and University of Wisconsin solution in adult liver transplantation

BACKGROUND: A safe and effective preservation solution is a precondition for successful orthotopic liver transplantation (OLT). This study compared University of Wisconsin (UW) and histidine-tryptophan-ketoglutarate (HTK) solutions in OLT. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 137 primary cadaveric. OLT performed between January 2003 and December 2006 at our institution. Sixty-eight grafts were harvested using UW and 69 using HTK. Recipients were managed similarly in regard to operative techniques and immunosuppression. We collected donor data including serum transaminases, serum sodium, ICU stay and assessed macroscopic liver quality. Recipient serum transaminases were collected on postoperative days 1, 7, 14, and 30. We compared biliary and vascular complications, as well as patient and graft survivals. RESULTS: Mean serum bilirubin levels were slightly higher in the HTK group at 1,7,14, and 30 days after transplantation, whereas transaminases were higher in the UW group. Primary nonfunction occurred in 1 patient in each group. Retransplantation was performed in 5 patients in the UW and in 9 patients in the HTK group. Biliary complication rates were similar in the UW and HTK groups (22% and 17%, respectively). Six arterial complications occurred in the HTK (8.7%) and 2 in the UW group (2.9%; P < .05). Mean follow-up was 25 months. Graft survival at 1, 12, and 36 months was 90%, 78%, and 75% versus 90%, 71%, and 71% in the UW versus HTK groups, respectively. One-, 12-, and 36-month patient survival rates were 93%, 78%, and 75% versus 93%, 78%, and 78% in the UW versus HTK groups, respectively. CONCLUSIONS: There were no significant differences in graft and patient survivals between the 2 groups. Whereas the biliary complication rates were comparable in both groups, the arterial complications were clearly higher in the UW group (8.7% vs 2.9%; P < .05%). UW and HTK solutions seemed to be equally safe and effective in the preservation of liver grafts. The high incidence of arterial complications in the UW group requires further prospective studies.     

体外持续肝脏灌注常温保存和HTK液低温保存无心跳供肝效果的比较

目的 比较应用组氨酸-色氨酸-酮戊二酸(HTK)液低温保存和体外持续肝脏灌注(ECLP)系统常温保存无心跳供肝的效果.方法 按保存方法不同将供肝随机分为A组和B组:供肝切取后,A组用HTK液在低温下保存10 h;B组用ECLP系统在常温下用稀释的自体血液持续灌注10 h.两组供肝再经过60 min冷缺血期后,连接ECLP系统用稀释的自体血液再灌注4 h.观察再灌注后1、2、3、4 h四个时间点的胆汁分泌量,门静脉和肝动脉的压力,肝脏耗氧率的变化,灌注液中丙氨酸转氨酶(ALT)、乳酸脱氢酶(LDH)、葡萄糖水平以及灌注后供肝的常规病理和超微病理变化.结果 B组再灌注后1、2、3、4 h时间点的胆汁分泌量,门静脉和肝动脉的压力,灌注液中ALT、LDH和葡萄糖水平,以及2、3、4 h时间点的耗氧率与A组比较,差异均有统计学意义(P＜0.05或P＜0.01);B组供肝的病理损害程度较A组轻.结论 供肝切取后10 h内,利用ECLP系统持续灌注常温保存比用HTK液单纯低温保存在维持无心跳供肝的功能和生理活性方面效果更好.     

Improved microcirculation by low‐viscosity histidine– tryptophan–ketoglutarate graft flush and subsequent cold storage in University of Wisconsin solution: results of an orthotopic rat liver transplantation model

As previously shown in a model of isolated rat liver perfusion, the combined use of an initial graft flush with low‐viscosity histidine–tryptophan–ketoglutarate (HTK) solution followed by cold storage in University of Wisconsin (UW) solution markedly improved the preservation during an extended cold storage period. In this study, we aimed to transfer our results into an in vivo model of orthotopic rat liver transplantation, and to elucidate the potential mechanism of the improved preservation by focusing on the hepatic microcirculation. Livers were harvested from male Wistar rats. Aortic perfusion with a pressure of 100 cm H₂O was performed with either UW (group UW) or HTK (groups UW and HTK_UW), followed by additional back‐table perfusion with UW (group HTK_UW). After 20‐h cold storage at 4 °C, livers were orthotopically transplanted with reconstructing the hepatic artery. As measured by bile flow and liver enzymes, HTK flush followed by UW storage was superior compared to single use of either UW or HTK solution. The hepatic microcirculation was significantly improved, as shown by the increased percentage of reperfused sinusoids and reduced sinusoidal leucostasis. HTK and UW effectively reduce ischaemia‐reperfusion injury after liver transplantation. By combining the comparative advantages of both solutions, a cumulative effect resulting in an improved preservation was shown. Thus, this mechanism improves microcirculatory reperfusion.     

Effect of Different Bile Duct Flush Solutions on Biliary Tract Preservation Injury of Donated Livers for Transplantation

Objectives

The objective of this study was to explore the effect of various bile duct flush (BDF) solutions on biliary tract preservation of donated livers in rats.

Methods

We studied the effects of BDF solutions and cold ischemic times on biliary tract preservation, using 2 kinds of solutions: (1) BDFa with normal saline (NS), or hypertonic citrate-adenine kidney preservation in vivo (HCA), and (2) BDFb with University of Wisconsin solution (UW), or histidine-tryptophan-ketoglutarate solution (HTK). The cold ischemic times (CIT) were 4, 8, or 12 hours. Forty-five healthy male Wistar rats were randomly divided into 9 groups of 5 rats each using a [L₉(3⁴)] orthogonal table. Biliary tract tissues were examined at the corresponding cold preservation times for the following: microscopic changes in bile duct cells; TUNEL (Transferase-mediated, dUTP-bitin nick end labeling) procedure assays apoptotic indices (AI) of endothelial cells in the biliary tract; ultrastructural changes; and average volumes (V) and density (Nd) of mitochondria in endothelial cells calculated using an image analysis system. The results were evaluated by analysis of variance (ANOVA) and direct analysis by an orthogonal design.

Results

AI of biliary tract endothelial cells showed significance (P < .01) of cold preservation of the biliary tract of donor liver with BDFa or BDFb and CIT; furthermore, HCA, HTK, and 4-hour CIT were all ideal. V and Nd of mitochondrial endothelial cells were significantly increased (P < .01) with BDFa, BDFb, and CIT; furthermore, factors HCA, HTK, and 4-hour CIT were all ideal.

Conclusions

Cold preservation injuries to the biliary tract of a donor liver may be greatly decreased by efficient and sufficient flushing of the bile tract. A suitable bile duct solution greatly decreases cold preservation injuries and protects endothelial cells.     

Evaluation of cysteine effect on redox potential of porcine liver preserved by simple hypothermia

Introduction

Cysteine (cys), a thiol amino-acid, is involved in de novo glutathione (GSH) synthesis in the extra- and intracellular space. It is also probably involved in the anaerobic glycolysis process. Both these facts may affect the metabolic condition of the liver preserved by simple hypothermia for transplantation. The aim of the study was to verify whether cysteine addition to histidine-tryptophan-ketoglutarate (HTK) organ preservation solution showed a positive effect on liver redox potential after 12-hour preservation in simple hypothermia.

Materials and methods

After collecting livers of Great White breed pigs that underwent 30 min of warm ischemia, before 30-min perfusion and cooling to 4°C with modified HTK solution containing cysteine prior to 12 h of preservation. Activity of glutathione reductase (GR), glutathione peroxidase (GPx), and superoxide dismutase (SOD) was determined in liver homogenates after perfusion and after the preservation period. The results were compared with pure HTK, Ringer's and reference University of Wisconsin (UW) solutions.

Results

30 min of perfusion and 12 h of cold preservation (CIT) in the Ringer's solution markedly increased GPx, SOD, and GR activities in liver homogenates compared with the activity using other fluids. After 12-h CIT the activities of GR, GPx and SOD were significantly higher in cys-modified HTK solution than the control HTK solution. They were comparable to the values recorded for the UW group.

Conclusions

Addition of cys to the HTK solution positively influenced the total pool of free radical scavengers in a liver undergoing 12-hour ischemia in the simple hypothermia, which was reflected in the elevated redox enzyme activity possibly due to cys participation in GSH synthesis.     

Association between donor-recipient serum sodium differences and orthotopic liver transplant graft function.

Previous studies have shown that donor hypernatremia and possibly recipient hyponatremia negatively impact graft function after orthotopic liver transplant (OLT). The purpose of this retrospective investigation was to determine whether measured differences in serum sodium values between cadaveric donors and OLT recipients (DeltaNa(+)) influence immediate postoperative allograft function and short-term patient outcomes. Two hundred and fifty patients that underwent OLT from January 2001 to December 2005 were included in this study. The DeltaNa(+) for each donor recipient pair was correlated with standard postoperative liver function tests as well as recipient length of intensive care unit stay (LOICUS), length of hospital stay (LOHS) and recipient survival. The relationship between donor hypernatremia (serum sodium >or= 155 mEq/mL), recipient hyponatremia (serum sodium level 相似文献   

Low viscosity histidine-tryptophan-ketoglutarate graft flush improves subsequent extended cold storage in University of Wisconsin solution in an extracorporeal rat liver perfusion and rat liver transplantation model.

Adequate flushing for liver donation requires large fluid volumes delivered at a high flow. This can be achieved more effectively with crystalloid solutions than with colloid-based solutions. This study examined the combination of initial histidine-tryptophan-ketoglutarate solution (HTK) graft flush and subsequent storage in University of Wisconsin solution (UW) to that of the single use of each solution. Livers from inbred Wistar rats were procured using aortic perfusion with UW or HTK for initial perfusion and reflushed after 30 minutes using either solution. In a third group, after perfusion with HTK, organs were reflushed with UW. A 60-minute in-vitro recirculating perfusion was performed after 24 hours of cold storage in the subsequent solution, as well as allotransplantation after 18 and 24 hours of cold storage. In extracorporeal perfusion, the HTK flush followed by UW storage was superior compared to the single use of either UW or HTK solution, as measured by portal venous pressure, bile flow, liver enzymes released into the effluent perfusate, glycerol leakage, and histological examinations. These data were consistent with the transplantation study. Histological damage and enzyme release after 5-day survival were lowest in the HTK flush and subsequent UW storage groups following 18 hours of cold storage; likewise, the 5-day survival was superior following 24 hours of cold storage. In conclusion, the combined use of HTK solution for initial graft rinse and subsequent storage in UW solution resulted in a cumulative protection. Choosing low-viscosity HTK solution for the initial organ flush may represent a feasible improvement in liver preservation, which also further reduces the required amount of UW solution.     

Optimising post-conditioning time of marginal donor livers

Background Due to the discrepancy between organ donors and receptors, the use of marginal livers (e.g., non-heart-beating-donor grafts) for transplantation purpose increased. The potential of a short-term aerobic machine perfusion (post-conditioning) for “less than optimal” grafts after cold storage (CS) was recently demonstrated. In our study, the optimal time course of post-conditioning (PC) is to be evaluated. Materials and methods Livers from male Wistar rats were withdrawn 30 min after cardiac arrest and flushed with histidine tryptophan ketoglutarate (HTK) solution. Then they were stored in HTK at 4°C for 18 h. After 16 h, some livers were put on PC by cold perfusion with HTK for 0.5, 1, 2 or 3 h. Afterwards, the viability of the organs was estimated by warm reperfusion (2 h) in vitro. Results After 1 h of PC, a significant increase in bile production and a decrease in enzyme release could be detected in comparison to CS. The adenosine triphosphate content of the PC livers after 1 h of treatment was significant higher than in CS organs. No markers for apoptosis could be detected after 1 h PC. Conclusion It can be concluded that a PC of 1 h after cold storage can ameliorate the organ viability of marginal livers. The extension or abbreviation of PC time seems to have no further beneficial effects. German Society of Surgery, Surgical Forum 2008, Best of Abstracts     

Combined Flush With Histidine-Tryptophan-Ketoglutarate and University of Wisconsin Solutions in Liver Transplantation: Preliminary Results

Introduction

Ischemia reperfusion injury (IRI) is the main cause of early allograft dysfunction (EAD) and subsequent primary allograft failure (PAF).

The impact of liver preservation in HTK and UW solution on microcirculation after liver transplantation

Severe microcirculatory disturbances due to endothelial cell damage and leukocyte adherence during reperfusion of transplanted livers are considered to contribute to early graft failure. Since the degree of reperfusion injury after liver transplantation depends on the length of preservation time and the solution used for preservation, the aim of our study was to assess three solutions with respect to microvascular perfusion and leukocyte adhesion. Therefore, rat livers were stored up to 24 h in Euro-Collins (EC), University of Wisconsin (UW), or histidin-tryphtophan-ketoglutarate (HTK) solutions prior to orthotopic transplantation. The livers were studied in situ 60 min postoperatively using intravital fluorescence video microscopy. Using simple syringe flushing (10 ml), sinusoidal perfusion decreased below 50% in EC preserved livers after 8 h preservation, in HTK preserved livers after 16 h preservation, and remained higher than 70% in livers preserved in UW up to 24 h. Permanent adhesion of leukocytes was increased more rapidly in organs after 1, 8, 16, and 24 h preservation in HTK (16%, 15%, 34%, and 49.7% ± 4.7%) compared to those preserved in UW (15%, 18%, 17%; and 32.7% ± 3.3%; P < 0.05). Using a 10-fold volumn of the organ weight of HTK solution during the harvesting procedure, with an 8 min equilibration period, sinusoidal perfusion (39.6 ± 4.7%) and leukocyte adhesion (42.7 ± 3.1%) were not improved after 24 h. In contrast, equilibration with a volumn of approximately 40-times the liver weight improved sinusoidal perfusion (70.8% ± 2.7%; P < 0.01) and leukocyte adhesion (24.9% ± 3.1%; P < 0.01) significantly. Thus, using HTK solution, simple flushing prior to long-term cold storage resulted in microcirculatory disturbances when compared to UW solution. Larger volumns of HTK solution with an additional equilibration period of 8 min, however, reduced leukocyte adhesion and improved sinusoidal perfusion to a similar degree as UW solution.     

减少肝移植术后胆道缺血性损伤的临床路径

目的：针对肝移植术后并发症缺血性胆道损伤（ITBL）,试图建立区分各种导致ITBL的危险因素的临床路径,降低ITBL的发生率。方法：记录随访335例行原位肝移植术（OLT）病例的可能导致胆道缺血的危险因素,包括供肝热缺血时间、冷缺血时间、温缺血时间及供肝脂肪肝情况等。按照冷缺血时间分两组I：TBL组和正常组。比较其他危险因素在两组间的差别。结果：冷缺血时间控制〈8 h,正常组81例,ITBL组2例,热缺血时间差别有统计学意义（P=0.017）;8～12 h,正常组150例I,TBL组25例,胆道温缺血时间差异有统计意义（P=0.033）;〉12 h,正常组57例I,TBL组20例,供肝脂肪肝发生率差异有统计学意义（P〈0.05）。结论：为避免ITBL,冷缺血时间〈8 hI,TBL的发生率很低,只要控制好热缺血时间即可;冷缺血时间8~12 h,尽量将胆道温缺血时间控制在1 h左右;冷缺血时间〉12 h,对于有严重脂肪变的边缘供体可以考虑弃用。