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Urology Apr 2015
Topics: Cold Ischemia; Female; Humans; Kidney Neoplasms; Male; Nephrectomy; Renal Insufficiency, Chronic; Warm Ischemia
PubMed: 25817109
DOI: 10.1016/j.urology.2014.11.047 -
Liver Transplantation : Official... Nov 2023The donor operation and the hemodynamics during declaration resulting in donor warm ischemia time have been linked to the outcomes in donation after circulatory death... (Review)
Review
Oxygen saturation during donor warm ischemia time and outcome of donation after circulatory death (DCD) liver transplantation with static cold storage: A review of 1114 cases.
The donor operation and the hemodynamics during declaration resulting in donor warm ischemia time have been linked to the outcomes in donation after circulatory death (DCD) liver transplantation (LT). Scrutiny of the donor hemodynamics at the time of withdrawal of life support concluded that a functional donor warm ischemia time may be associated with LT graft failure. Unfortunately, the definition for functional donor warm ischemia time has not reached a consensus-but has almost always incorporated time spent in a hypoxic state. Herein, we reviewed 1114 DCD LT cases performed at the 20 highest volume centers during 2014 and 2018. Donor hypoxia began within 3 minutes of withdrawal of life support for 60% of cases and within 10 minutes for 95% of cases. Graft survival was 88.3% at 1 year and 80.3% at 3 years. Scrutinizing the time spent under hypoxic conditions (oxygen saturation ≤ 80%) during the withdrawal of life support, we found an increasing risk of graft failure as hypoxic time increased from 0 to 16 minutes. After 16 minutes and up to 50 minutes, we did not find any increased risk of graft failure. In conclusion, after 16 minutes of time in hypoxia, the risk of graft failure in DCD LT did not increase. The current evidence suggests that an over-reliance on hypoxia time may lead to an unnecessary increase in DCD liver discard and may not be as useful for predicting graft loss after LT.
Topics: Humans; Warm Ischemia; Liver Transplantation; Oxygen Saturation; Donor Selection; Risk Factors; Tissue Donors; Hypoxia; Graft Survival; Retrospective Studies; Tissue and Organ Procurement; Death
PubMed: 37076131
DOI: 10.1097/LVT.0000000000000162 -
Biopreservation and Biobanking Aug 2021High-quality RNA extraction from tissue samples is of key importance for scientific research and translational medicine. Tissue collection and preparation may affect...
High-quality RNA extraction from tissue samples is of key importance for scientific research and translational medicine. Tissue collection and preparation may affect RNA quality. In this study, we investigated effects of warm ischemia time, cryopreservation, and grinding methods on RNA quality. Total RNA was extracted from mouse kidney tissues with warm ischemia times of 0, 30, 60, 90, and 120 minutes. Half of the tissues were used to extract RNA immediately, while the others were cryopreserved in the vapor phase of liquid nitrogen for 6 months before RNA extraction. A mortar, homogenizer, and tissue lyser were used to grind tissues. RNA was extracted by TRIzol, and RNA integrity was assessed by the RNA integrity number (RIN) value. For fresh tissues and frozen tissues with warm ischemia time within 60 minutes, RIN values were above 7.0 and remained above 6.0 with warm ischemia time within 120 minutes. For the same warm ischemia time, RIN values of frozen tissues were slightly lower than those of fresh tissues. No significant RIN value alterations were observed among grinding methods, but for RNA extraction efficiency, a mortar was much less efficient than the homogenizer or tissue lyser. For frozen tissues, RNA tended to degrade within 8 minutes at room temperature. Mouse kidney tissues with a warm ischemia time within 120 minutes are suitable for general RNA-related research. For tissues with a warm ischemia time within 60 minutes, cryopreservation may not affect RNA quality. The duration of frozen tissues held at room temperature before grinding affects the integrity of RNA, while grinding methods do not affect RNA integrity.
Topics: Animals; Cryopreservation; Kidney; Mice; RNA; Tissue Banks; Warm Ischemia
PubMed: 33577406
DOI: 10.1089/bio.2020.0129 -
Experimental Biology and Medicine... May 2019Over the past several decades, ex vivo perfusion has emerged as a promising technology for the assessment, preservation, and recovery of donor organs. Many exciting... (Review)
Review
Over the past several decades, ex vivo perfusion has emerged as a promising technology for the assessment, preservation, and recovery of donor organs. Many exciting pre-clinical findings have now been translated to clinical use, and successful transplantation following ex vivo perfusion has been achieved for heart, lung, and liver. While machine perfusion provides distinct advantages over traditional cold preservation, many challenges remain, including that of long-term (multi-day) ex vivo support. Here, we provide an overview of the current status of ex vivo machine perfusion in the pre-clinical and clinical setting and share our perspective on the future direction of the field.
Topics: Bioengineering; Cadaver; Cold Ischemia; Forecasting; Heart; Heart Transplantation; Humans; Liver; Liver Transplantation; Lung; Lung Transplantation; Organ Preservation; Perfusion; Reperfusion Injury; Tissue and Organ Harvesting; Transplants; Warm Ischemia
PubMed: 30889963
DOI: 10.1177/1535370219834498 -
Current Opinion in Organ Transplantation Aug 2022This review describes recent developments in the field of liver perfusion techniques. (Review)
Review
PURPOSE OF REVIEW
This review describes recent developments in the field of liver perfusion techniques.
RECENT FINDINGS
Dynamic preservation techniques are increasingly tested due to the urgent need to improve the overall poor donor utilization. With their exposure to warm ischemia, livers from donors after circulatory death (DCD) transmit additional risk for severe complications after transplantation. Although the superiority of dynamic approaches compared to static-cold-storage is widely accepted, the number of good quality studies remains limited. Most risk factors, particularly donor warm ischemia, and accepted thresholds are inconsistently reported, leading to difficulties to assess the impact of new preservation technologies. Normothermic regional perfusion (NRP) leads to good outcomes after DCD liver transplantation, with however short ischemia times. While randomized controlled trials (RCT) with NRP are lacking, results from the first RCTs with ex-situ perfusion were reported. Hypothermic oxygenated perfusion was shown to protect DCD liver recipients from ischemic cholangiopathy. In contrast, endischemic normothermic perfusion seems to not impact on the development of biliary complications, although this evidence is only available from retrospective studies.
SUMMARY
Dynamic perfusion strategies impact posttransplant outcomes and are increasingly commissioned in various countries along with more evidence from RCTs. Transparent reporting of risk and utilization with uniform definitions is required to compare the role of different preservation strategies in DCD livers with prolonged ischemia times.
Topics: Humans; Organ Preservation; Graft Survival; Perfusion; Warm Ischemia; Tissue Donors; Liver; Ischemia
PubMed: 35438271
DOI: 10.1097/MOT.0000000000000963 -
European Urology Jul 2015Partial nephrectomy (PN) is the current gold standard treatment for small localized renal tumors.; however, the impact of duration and type of intraoperative ischemia on... (Review)
Review
CONTEXT
Partial nephrectomy (PN) is the current gold standard treatment for small localized renal tumors.; however, the impact of duration and type of intraoperative ischemia on renal function (RF) after PN is a subject of significant debate.
OBJECTIVE
To review the current evidence on the relationship of intraoperative ischemia and RF after PN.
EVIDENCE ACQUISITION
A review of English-language publications on renal ischemia and RF after PN was performed from 2005 to 2014 using the Medline, Embase, and Web of Science databases. Ninety-one articles were selected with the consensus of all authors and analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria.
EVIDENCE SYNTHESIS
The vast majority of reviewed studies were retrospective, nonrandomized observations. Based on the current literature, RF recovery after PN is strongly associated with preoperative RF and the amount of healthy kidney parenchyma preserved. Warm ischemia time (WIT) is modifiable and prolonged warm ischemia is significantly associated with adverse postoperative RF. Available data suggest a benefit of keeping WIT <25min, although the level of evidence to support this threshold is limited. Cold ischemia safely facilitates longer durations of ischemia. Surgical techniques that minimize or avoid global ischemia may be associated with improved RF outcomes.
CONCLUSIONS
Although RF recovery after PN is strongly associated with quality and quantity of preserved kidney, efforts should be made to limit prolonged WIT. Cold ischemia should be preferred when longer ischemia is expected, especially in presence of imperative indications for PN. Additional research with higher levels of evidence is needed to clarify the optimal use of renal ischemia during PN.
PATIENT SUMMARY
In this review of the literature, we looked at predictors of renal function after surgical resection of renal tumors. There is a strong association between the quality and quantity of renal tissue that is preserved after surgery and long-term renal function. The time of interruption of renal blood flow during surgery is an important, modifiable predictor of postoperative renal function.
Topics: Carcinoma, Renal Cell; Cold Ischemia; Humans; Kidney Neoplasms; Nephrectomy; Nephrons; Organ Sparing Treatments; Postoperative Complications; Renal Insufficiency; Warm Ischemia
PubMed: 25703575
DOI: 10.1016/j.eururo.2015.01.025 -
ASAIO Journal (American Society For... Oct 2022In donation after circulatory death donors, warm ischemia time is a significant threat to successful cardiac transplantation. The ability to perfuse these organs during...
In donation after circulatory death donors, warm ischemia time is a significant threat to successful cardiac transplantation. The ability to perfuse these organs during the minutes after death, until cardiac evaluation is completed to satisfaction, is crucial in limiting total warm ischemic time. Thoracoabdominal normothermic regional perfusion (TANRP) has emerged as a promising strategy for recovering and monitoring these hearts. We propose a series of clinical practice pearls that we follow for all donation after circulatory death procurements to streamline the process of setting up a TANRP circuit and ensuring all team members present at time procurement are familiar with the procedure. Bicaval cannulation is achieved via the abdomen for aortic cannulation, and via the chest for right atrial cannulation, avoiding deairing maneuvers and providing the shortest possible duration from incision to initiation of cardiopulmonary bypass. Here, we describe a series of practice techniques which we have utilized in our early experience with TANRP.
Topics: Heart Transplantation; Humans; Organ Preservation; Perfusion; Tissue Donors; Tissue and Organ Procurement; Warm Ischemia
PubMed: 35439176
DOI: 10.1097/MAT.0000000000001749 -
European Urology Oncology Apr 2024We contextualize controversial evidence on the impact of warm ischemia on functional outcomes after partial nephrectomy for localized renal tumors and provide a holistic...
We contextualize controversial evidence on the impact of warm ischemia on functional outcomes after partial nephrectomy for localized renal tumors and provide a holistic framework for re-envisioning the dilemma of off-clamp versus on-clamp surgery. The focus should shift away from the surgeon towards patient- and kidney-related characteristics.
Topics: Humans; Treatment Outcome; Nephrectomy; Kidney Neoplasms; Warm Ischemia
PubMed: 38245480
DOI: 10.1016/j.euo.2023.12.009 -
International Journal of Molecular... Aug 2021Ischemia/reperfusion injury (IRI) remains a significant problem to be solved in uterus transplantation (UTx). Melatonin and glycine have been shown to possess direct...
Ischemia/reperfusion injury (IRI) remains a significant problem to be solved in uterus transplantation (UTx). Melatonin and glycine have been shown to possess direct cytoprotective activities, mainly due to their antioxidative and anti-inflammatory properties. The aim of this study was to investigate the protective effects of melatonin and glycine and their combination on IRI in a rat model of warm ischemia. In this study, rats were assigned to eight groups, including sham and IRI ( = 80). Melatonin and glycine alone or their combination were administered prior to 1 h of uterus ischemia followed by 1 h of reperfusion. Melatonin (50 mg/kg) was administered via gavage 2 h before IRI and glycine in an enriched diet for 5 days prior to intervention. Uterus IRI was estimated by histology, including immunohistochemistry, and biochemical tissue analyses. Histology revealed that uterus IRI was significantly attenuated by pretreatment with melatonin ( = 0.019) and glycine ( = 0.044) alone as well as their combination ( = 0.003). Uterus IRI led to increased myeloperoxidase expression, which was significantly reduced by melatonin ( = 0.004), glycine ( < 0.001) or their combination ( < 0.001). The decline in superoxide dismutase activity was significantly reduced in the melatonin ( = 0.027), glycine ( = 0.038) and combined treatment groups ( = 0.015) when compared to the IRI control group. In conclusion, melatonin, glycine and their combination significantly reduced oxidative stress-induced cell damage after IRI in a small animal warm ischemia model, and, therefore, clinical studies are required to evaluate the protective effects of these well-characterized substances in uterus IRI.
Topics: Animals; Antioxidants; Disease Models, Animal; Female; Glycine; Glycine Agents; Melatonin; Rats; Rats, Sprague-Dawley; Reperfusion Injury; Uterus; Warm Ischemia
PubMed: 34445081
DOI: 10.3390/ijms22168373 -
The Journal of Heart and Lung... Feb 2019Euthanasia is categorically prohibited in almost all countries throughout the world. In Belgium and the Netherlands, combining euthanasia and subsequent organ donation...
Euthanasia is categorically prohibited in almost all countries throughout the world. In Belgium and the Netherlands, combining euthanasia and subsequent organ donation in a so-called donation after circulatory-death (DCD) procedure is feasible on legal and medical grounds, and is increasingly gaining social and ethical acceptance. However, heart transplantation after DCD is currently not performed in Belgium and the Netherlands after euthanasia due to concerns surrounding the prolonged warm ischemia time associated with DCD and its effect on subsequent heart function. A number of patients who undergo euthanasia explicitly express their wish to donate their organs in a "living organ donation" procedure, which then causes death. Assuming that euthanasia is permitted, as expressed in Dutch and Belgian legislation, this exploratory article addresses whether it is legally and ethically sound to donate organs, especially the heart, as a living donor and to perform euthanasia in the same procedure in a patient who fulfills the due diligence requirements for euthanasia. Organ donation euthanasia (ODE) would then cause death by the associated surgical procedure, and in addition would improve the quality of the other donated organs, a procedure that would fully respect the patient's autonomy.
Topics: Belgium; Euthanasia; Humans; Living Donors; Netherlands; Organ Transplantation; Tissue and Organ Procurement; Warm Ischemia
PubMed: 30197210
DOI: 10.1016/j.healun.2018.07.014