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Machine Perfusion (machine + perfusion)
Kinds of Machine Perfusion Selected AbstractsEditorial: Cold Machine Perfusion or Static Cold Storage of Kidneys: Why the Debate ContinuesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010W. D. Irish The debate regarding the efficacy of cold machine perfusion versus static cold storage for prevention of delayed graft function in organs from deceased donors continues, despite the results of two well-designed clinical trials. See article by Watson et al on page 1991. [source] Cold Machine Perfusion Versus Static Cold Storage of Kidneys Donated After Cardiac Death: A UK Multicenter Randomized Controlled TrialAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010C. J. E. Watson One third of deceased donor kidneys for transplantation in the UK are donated following cardiac death (DCD). Such kidneys have a high rate of delayed graft function (DGF) following transplantation. We conducted a multicenter, randomized controlled trial to determine whether kidney preservation using cold, pulsatile machine perfusion (MP) was superior to simple cold storage (CS) for DCD kidneys. One kidney from each DCD donor was randomly allocated to CS, the other to MP. A sequential trial design was used with the primary endpoint being DGF, defined as the necessity for dialysis within the first 7 days following transplant. The trial was stopped when data were available for 45 pairs of kidneys. There was no difference in the incidence of DGF between kidneys assigned to MP or CS (58% vs. 56%, respectively), in the context of an asystolic period of 15 min and median cold ischemic times of 13.9 h for MP and 14.3 h for CS kidneys. Renal function at 3 and 12 months was similar between groups, as was graft and patient survival. For kidneys from controlled DCD donors (with mean cold ischemic times around 14 h), MP offers no advantage over CS, which is cheaper and more straightforward. [source] An In Vivo Autotransplant Model of Renal Preservation: Cold Storage Versus Machine Perfusion in the Prevention of Ischemia/Reperfusion InjuryARTIFICIAL ORGANS, Issue 7 2009Gaetano La Manna Abstract There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation. Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion (n = 6) or cold storage (n = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5,-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation. The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys. The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage. [source] Inhibition of TXA2 synthesis with OKY-046 improves liver preservation by prolonged hypothermic machine perfusion in ratsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7pt2 2008Hongzhi Xu Abstract Background and Aim:, We previously reported that hypothermic machine perfusion (HMP) for liver preservation is feasible, but hepatic microcirculatory dysfunction and significant liver damage remain major obstacles in its application when the preservation is extended to 24 h. The underlying injury mechanism is not well understood. The present study sought to investigate the role of thromboxane A2 (TXA2) in the pathogenesis of liver injury after prolonged HMP. Methods:, Livers isolated from Sprague,Dawley rats were subjected to continuous machine perfusion with University of Wisconsin (UW) solution at a flow rate of 0.4 mL/min/g liver at 4°C for 24 h. A specific TXA2 synthase inhibitor, OKY-046 (OKY), was added to UW solution during the preservation period and to the Krebs,Henseleit buffer during reperfusion. The performance of the livers after preservation was evaluated using an isolated liver perfusion system with Krebs,Henseleit buffer at a flow rate of 15 mL/min at 37°C for 30 min. Results:, Prolonged HMP induced a significant release of TXA2 into the portal circulation as indicated by markedly increased levels of TXB2 in the perfusate during reperfusion (at 30 min, 1447.4 ± 163.6 pg/mL vs 50.91 ± 6.7 pg/mL for control). Inhibition of TXA2 synthesis with OKY significantly decreased releases of TXA2 (69.8 ± 13.4 pg/mL) concomitant with reduced lactate dehydrogenase (LDH) releases (at 30 min, HMP + OKY: 144.9 ± 27.9 U/L; HMP: 369.3 ± 68.5 U/L; simple cold storage or SCS: 884.4 ± 80.3 U/L), decreased liver wet/dry weight ratio (HMP + OKY vs SCS and HMP: 3.6 ± 0.3 vs 4.4 ± 0.1 and 3.9 ± 0.2, respectively) and increased hyaluronic acid uptake (at 30 min, HMP + OKY vs SCS, HMP: 33.1 ± 2.9% vs 13.9 ± 3.6%, 18.6 ± 2.4%, respectively). Liver histology also showed significant improvement in tissue edema and hepatocellular necrosis with OKY compared with HMP without OKY. Conclusion:, The results demonstrate that TXA2 is involved in the development of hepatocellular injury induced by HMP, and inhibition of TXA2 synthesis during preservation and reperfusion protects liver hepatocytes and sinusoidal endothelial cells from injuries caused by prolonged HMP. [source] Editorial: Cold Machine Perfusion or Static Cold Storage of Kidneys: Why the Debate ContinuesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010W. D. Irish The debate regarding the efficacy of cold machine perfusion versus static cold storage for prevention of delayed graft function in organs from deceased donors continues, despite the results of two well-designed clinical trials. See article by Watson et al on page 1991. [source] Cold Machine Perfusion Versus Static Cold Storage of Kidneys Donated After Cardiac Death: A UK Multicenter Randomized Controlled TrialAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2010C. J. E. Watson One third of deceased donor kidneys for transplantation in the UK are donated following cardiac death (DCD). Such kidneys have a high rate of delayed graft function (DGF) following transplantation. We conducted a multicenter, randomized controlled trial to determine whether kidney preservation using cold, pulsatile machine perfusion (MP) was superior to simple cold storage (CS) for DCD kidneys. One kidney from each DCD donor was randomly allocated to CS, the other to MP. A sequential trial design was used with the primary endpoint being DGF, defined as the necessity for dialysis within the first 7 days following transplant. The trial was stopped when data were available for 45 pairs of kidneys. There was no difference in the incidence of DGF between kidneys assigned to MP or CS (58% vs. 56%, respectively), in the context of an asystolic period of 15 min and median cold ischemic times of 13.9 h for MP and 14.3 h for CS kidneys. Renal function at 3 and 12 months was similar between groups, as was graft and patient survival. For kidneys from controlled DCD donors (with mean cold ischemic times around 14 h), MP offers no advantage over CS, which is cheaper and more straightforward. [source] Hypothermic Machine Preservation in Human Liver Transplantation: The First Clinical SeriesAMERICAN JOURNAL OF TRANSPLANTATION, Issue 2 2010J. V. Guarrera Hypothermic machine perfusion (HMP) is widely used to preserve kidneys for transplantation with improved results over cold storage (CS). To date, successful transplantation of livers preserved with HMP has been reported only in animal models. In this, the first prospective liver HMP study, 20 adults received HMP-preserved livers and were compared to a matched group transplanted with CS livers. HMP was performed for 3,7 h using centrifugal perfusion with Vasosol® solution at 4,6°C. There were no cases of primary nonfunction in either group. Early allograft dysfunction rates were 5% in the HMP group versus 25% in controls (p = 0.08). At 12 months, there were two deaths in each group, all unrelated to preservation or graft function. There were no vascular complications in HMP livers. Two biliary complications were observed in HMP livers compared with four in the CS group. Serum injury markers were significantly lower in the HMP group. Mean hospital stay was shorter in the HMP group (10.9 ± 4.7 days vs. 15.3 ± 4.9 days in the CS group, p = 0.006). HMP of donor livers provided safe and reliable preservation in this pilot case-controlled series. Further multicenter HMP trials are now warranted. [source] ASTS Recommended Practice Guidelines for Controlled Donation after Cardiac Death Organ Procurement and TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2009D. J. Reich The American Society of Transplant Surgeons (ASTS) champions efforts to increase organ donation. Controlled donation after cardiac death (DCD) offers the family and the patient with a hopeless prognosis the option to donate when brain death criteria will not be met. Although DCD is increasing, this endeavor is still in the midst of development. DCD protocols, recovery techniques and organ acceptance criteria vary among organ procurement organizations and transplant centers. Growing enthusiasm for DCD has been tempered by the decreased yield of transplantable organs and less favorable posttransplant outcomes compared with donation after brain death. Logistics and ethics relevant to DCD engender discussion and debate among lay and medical communities. Regulatory oversight of the mandate to increase DCD and a recent lawsuit involving professional behavior during an attempted DCD have fueled scrutiny of this activity. Within this setting, the ASTS Council sought best-practice guidelines for controlled DCD organ donation and transplantation. The proposed guidelines are evidence based when possible. They cover many aspects of DCD kidney, liver and pancreas transplantation, including donor characteristics, consent, withdrawal of ventilatory support, operative technique, ischemia times, machine perfusion, recipient considerations and biliary issues. DCD organ transplantation involves unique challenges that these recommendations seek to address. [source] Donation after Cardiac Death Kidneys with Low Severity Pre-Arrest Acute Renal FailureAMERICAN JOURNAL OF TRANSPLANTATION, Issue 3 2007S. Sohrabi The widening gap between supply and demand for renal transplantation has prompted many centers to use donors after cardiac death. Some of these donors exhibit signs of acute renal failure (ARF) prior to cardiac arrest. Concern has been expressed about poor quality of graft function from such donors. In response to this perception, we reviewed 49 single renal transplant recipients from category III donors after cardiac death between 1998 and 2005, at out center. All kidneys but one had hypothermic machine perfusion and viability testing prior to transplantation. According to the RIFLE criteria, nine recipients had kidneys from donors with "low severity pre-arrest ARF". The remainder of the recipients were used as control group. There was no statistical significant difference in delayed graft function and rejection rates between these two groups. Recipients GFR at 12 months was 44.4 ± 17.1 and 45.2 ± 14.7 (mL/min/1.73m2) from donors with ARF and without ARF, respectively (p = 0.96). In conclusion, low severity ARF in kidneys from controlled after cardiac death donors can be a reversible condition after transplantation. Short-term results are comparable to the kidneys from same category donors without renal failure, providing that some form of viability assessment is implemented prior to transplantation. [source] An In Vivo Autotransplant Model of Renal Preservation: Cold Storage Versus Machine Perfusion in the Prevention of Ischemia/Reperfusion InjuryARTIFICIAL ORGANS, Issue 7 2009Gaetano La Manna Abstract There is increasing proof that organ preservation by machine perfusion is able to limit ischemia/reperfusion injury in kidney transplantation. This study was designed to compare the efficiency in hypothermic organ preservation by machine perfusion or cold storage in an animal model of kidney autotransplantation. Twelve pigs underwent left nephrectomy after warm ischemic time; the organs were preserved in machine perfusion (n = 6) or cold storage (n = 6) and then autotransplanted with immediate contralateral nephrectomy. The following parameters were compared between the two groups of animals: hematological and urine indexes of renal function, blood/gas analysis values, histological features, tissue adenosine-5,-triphosphate (ATP) content, perforin gene expression in kidney biopsies, and organ weight changes were compared before and after preservation. The amount of cellular ATP was significantly higher in organs preserved by machine perfusion; moreover, the study of apoptosis induction revealed an enhanced perforin expression in the kidneys, which underwent simple hypothermic preservation compared to the machine-preserved ones. Organ weight was significantly decreased after cold storage, but it remained quite stable for machine-perfused kidneys. The present model seems to suggest that organ preservation by hypothermic machine perfusion is able to better control cellular impairment in comparison with cold storage. [source] Pulsatile machine perfusion vs. cold storage of kidneys for transplantation: a rapid and systematic reviewCLINICAL TRANSPLANTATION, Issue 4 2003Jeremy P Wight Abstract: Objective: To identify and prioritize key areas for further research in kidney preservation systems. Materials and methods: We conducted a systematic review and meta-analysis of the effectiveness of machine perfusion and cold storage techniques in reducing delayed graft function (DGF) and improving graft survival in recipients of kidneys from beating and non-heart-beating donors. Literature quantifying the link between DGF and graft survival was used to evaluate the potential long-term impact of machine perfusion and cold storage systems. Cox proportional hazards modelling was used to predict graft survival and graft years gained over 10 yr. Monte Carlo sensitivity analysis was conducted to evaluate stochastic uncertainties within the model. Results: Machine perfusion leads to a relative risk of DGF of approximately 80% (67%, 96%) compared with cold storage, although the evidence base is limited in quality and study size. Direct evidence on graft survival at 1 yr demonstrates no statistically significant difference between machine perfusion and cold storage. Predictions based upon quantifying the link between DGF and graft survival suggest potential improvements of between 0 and 6% at 10 yr. Discussion: Studies of high methodological quality and sufficient size are required to determine whether machine preservation leads to reduce rates of DGF. Predicted impact on graft survival implies that direct evidence would require a large population followed up over a long period of time. Registry database analysis supported by validation of the link between DGF and graft survival may be preferable and more feasible than randomized controlled trials. [source] | ||||||||||