The continuing shortage of deceased donor organs for transplantation, and the limited number of potential donors after brain death, has led to a resurgence of interest in donation after circulatory ...death (DCD). The processes of warm and cold ischemia threaten the viability of DCD organs, but these can be minimized by well-organized DCD pathways and new techniques of in situ organ preservation and ex situ resuscitation and repair post-explantation. Transplantation survival after DCD is comparable to donation after brain death despite higher rates of primary non-function and delayed graft function. Countries with successfully implemented DCD programs have achieved this primarily through the establishment of national ethical, professional and legal frameworks to address both public and professional concerns with all aspects of the DCD pathway. It is unlikely that expanding standard DCD programs will, in isolation, be sufficient to address the worldwide shortage of donor organs for transplantation. It is therefore likely that reliance on extended criteria donors will increase, with the attendant imperative to minimize ischemic injury to candidate organs. Normothermic regional perfusion and ex situ perfusion techniques allow enhanced preservation, assessment, resuscitation and/or repair of damaged organs as a way of improving overall organ quality and preventing the unnecessary discarding of DCD organs. This review will outline exemplar controlled and uncontrolled DCD pathways, highlighting practical and logistical considerations that minimize warm and cold ischemia times while addressing potential ethical concerns. Future perspectives will also be discussed.
Donation after circulatory death Manara, A.R.; Murphy, P.G.; O’Callaghan, G.
British journal of anaesthesia : BJA,
January 2012, 20120100, 2012-Jan, 2012-01-00, 20120101, Letnik:
108, Številka:
suppl_1
Journal Article
Recenzirano
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Donation after circulatory death (DCD) describes the retrieval of organs for the purposes of transplantation that follows death confirmed using circulatory criteria. The persisting shortfall in the ...availability of organs for transplantation has prompted many countries to re-introduce DCD schemes not only for kidney retrieval but increasingly for other organs with a lower tolerance for warm ischaemia such as the liver, pancreas, and lungs. DCD contrasts in many important respects to the current standard model for deceased donation, namely donation after brain death. The challenge in the practice of DCD includes how to identify patients as suitable potential DCD donors, how to support and maintain the trust of bereaved families, and how to manage the consequences of warm ischaemia in a fashion that is professionally, ethically, and legally acceptable. Many of the concerns about the practice of both controlled and uncontrolled DCD are being addressed by increasing professional consensus on the ethical and legal justification for many of the interventions necessary to facilitate DCD. In some countries, DCD after the withdrawal of active treatment accounts for a substantial proportion of deceased organ donors overall. Where this occurs, there is an increased acceptance that organ and tissue donation should be considered a routine part of end-of-life care in both intensive care unit and emergency department.
Summary
Organ donation after brain death remains the deceased organ donation pathway of choice. In the UK, the current identification and referral rate for potential donation after brain death donors ...is 99%, the testing rate for determining death using neurological criteria is 86% and the approach to families for donation is 91%. Increasing donation after brain death donation will primarily require a large increase in the current consent rate of 72% to one matching the consent rate of 80–90% achieved in other European countries. Implementing the use of evidence‐based donor optimisation bundles may increase the number of organs available for transplantation. Alternatively, the UK will need to look at more challenging ways of increasing the pool of potential donors after brain death. The first would be to delay the withdrawal of life‐sustaining treatment in patients with devastating brain injury to allow progression to brain death after the family have given consent to organ donation and with their consent to this delay. Even more challenging would be the consideration of re‐introducing intensive care to facilitate organ donation programmes that have been so successful at increasing the number of organ donors elsewhere.
International perspective on the diagnosis of death Gardiner, D.; Shemie, S.; Manara, A. ...
British journal of anaesthesia : BJA,
January 2012, 20120100, 2012-Jan, 2012-01-00, 20120101, Letnik:
108, Številka:
suppl_1
Journal Article
Recenzirano
Odprti dostop
There is growing medical consensus in a unifying concept of human death. All human death involves the irreversible loss of the capacity for consciousness, combined with the irreversible loss of the ...capacity to breathe. Death then is a result of the irreversible loss of these functions in the brain. This paper outlines three sets of criteria to diagnose human death. Each set of criteria clearly establishes the irreversible loss of the capacity for consciousness, combined with the irreversible loss of the capacity to breathe. The most appropriate set of criteria to use is determined by the circumstances in which the medical practitioner is called upon to diagnose death. The three criteria sets are somatic (features visible on external inspection of the corpse), circulatory (after cardiorespiratory arrest), and neurological (in patients in coma on mechanical ventilation); and represent a diagnostic standard in which the medical profession and the public can have complete confidence. This review unites authors from Australia, Canada, and the UK and examines the medical criteria that we should use in 2012 to diagnose human death.
This systematic review delineates the effect of primary therapeutic hypothermia (PTH) (initiated on presentation of the patient) on both mortality and neurological outcome in patients with traumatic ...brain injury. The safety profile of the therapy is also assessed. A systematic search of the following databases was performed: MEDLINE, EMBASE, Zetoc database of conference proceedings, the Cochrane Database of Systematic Reviews, and the ClinicalTrials.gov website, up to July 28, 2011. Relevant journals were hand-searched for further articles and reference lists were checked against the retrieved results for additional resources. The retrieved results were filtered for randomized controlled trials in English where systemic hypothermia was applied for ≥12 h in the treatment arm and outcome was assessed at a minimum of 3 months. Randomized controlled trials were assessed for quality of evidence using the GRADE system. Eighteen randomized controlled trials (1851 patients) were identified. The overall relative risk of mortality with PTH when compared with controls was 0.84 95% confidence interval (CI)=0.72–0.98 and of poor neurological outcome was 0.81 (95% CI=0.73–0.89). However, when only high-quality trials were analysed, the relative risks were 1.28 (95% CI=0.89–1.83) and 1.07 (95% CI=0.92–1.24), respectively. Hypothermia was associated with cerebrovascular disturbances on rewarming and possibly with pneumonia in adult patients. Given the quality of the data currently available, no benefit of PTH on mortality or neurological morbidity could be identified. The therapy should therefore only be used within the confines of well-designed clinical trials.
Patients with severe grades of life-threatening brain injury are commonly characterized as having devastating brain injury (DBI), which we have defined as: ‘any neurological condition that is ...assessed at the time of hospital admission as an immediate threat to life or incompatible with good functional recovery AND where early limitation or withdrawal of therapy is being considered’. The outcome in patients with DBI is often death or severe disability, and as a consequence rapid withdrawal of life sustaining therapies is commonly contemplated or undertaken. However, accurate prognostication in life-threatening brain injury is difficult, particularly at an early stage. Evidence from controlled studies to guide decision-making is limited, and there is a risk of a ‘self-fulfilling prophecy’, with early prognostication leading to early withdrawal of life sustaining therapies and death. The Joint Professional Standards committee of the Faculty of Intensive Care Medicine and the Intensive Care Society convened a consensus group with representation from stakeholder professional organizations to develop clear professional guidance in this area. It recognized that the weak evidence base makes GRADE guidelines difficult to justify. We have made 12 practical, pragmatic recommendations to help clinicians deliver safe, effective, equitable, and justifiable care within resource constrained healthcare systems. In the situation where patient-centred outcomes are recognized to be unacceptable, regardless of the extent of neurological improvement, then early transition to palliative care is appropriate. These recommendations are intended to apply where the primary pathology is DBI, rather than where DBI has compounded a progressive and irreversible deterioration in other life-threatening comorbidities.
Summary
The refusal rate for organ donation in the UK is 42%, among the highest in Europe. We extracted data on every family approach for donation in UK ICUs or Emergency Departments between 1st ...April 2012 and 30th September 2013, and performed multiple logistic regression to identify modifiable factors associated with consent. Complete data were available for 4703 of 4899 approaches during the study period. Consent for donation after brain death was 68.9%, and for donation after circulatory death 56.5% (p < 0.0001). Patient ethnicity, knowledge of a patient's wishes and involvement of a specialist nurse in organ donation in the approach were strongly associated with consent (p < 0.0001). The impact of the specialist nurse was stronger for donation after circulatory death than for donation after brain death, even after accounting for the impact of prior knowledge of patients' wishes. Involvement of the specialist nurse in the approach, encouraging family discussions about donation wishes and promotion of the organ donor register are key strategies to increase UK consent rates, and are supported by this study.
Sequential digital dermoscopy (SDD) enables the diagnosis of a subgroup of slow-growing melanomas that lack suspicious features at baseline examination but exhibit detectable change on follow-up. The ...combined use of total-body photography and SDD is recommended in high-risk subjects by current guidelines. To establish the usefulness of SDD for low-risk individuals, we conducted a retrospective study using electronic medical records of low-risk patients with a histopathological diagnosis of cutaneous melanoma between 1 January 2016 and 31 December 2019, who had been referred and monitored for long-term follow-up of clinically suspicious melanocytic nevi. We sought to compare the distribution of "early" cutaneous melanoma, defined as melanoma in situ and pT1a melanoma, between SDD and periodical handheld dermoscopy in low-risk patients. A total of 621 melanomas were diagnosed in a four-year timespan; 471 melanomas were diagnosed by handheld dermoscopy and 150 by digital dermoscopy. Breslow tumor thickness was significantly higher for melanomas diagnosed by handheld compared to digital dermoscopy (0.56 ± 1.53 vs. 0.26 ± 0.84,
= 0.030, with a significantly different distribution of pT stages between the two dermoscopic techniques. However, no significant difference was found with respect to the distribution of pT stages, mean Breslow tumor thickness, ulceration, and prevalence of associated melanocytic nevus in tumors diagnosed on periodical handheld dermoscopy compared to SDD. Our results confirm that periodical dermoscopic examination enables the diagnosis of cutaneous melanoma at an earlier stage compared to first-time examination as this was associated in our patients with better prognostic features. However, in our long-term monitoring of low-risk subjects, Breslow tumor thickness and pT stage distribution did not differ between handheld periodical dermoscopy and SDD.
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