donation process is more predictable with only a small proportion of cases not proceeding to the surgical retrieval of transplantable organs. The number of DBD donors is limited by the low and decreasing incidence of stroke, brain trauma and other causes of brain death observed in many developed countries including Australia and New Zealand. This means that DBD is possible in fewer than 1% of the deaths that occur in hospital. April 2021 version 1.5 7 Death is more commonly determined using circulatory criteria and—in a limited number of such circumstances— organ donation may be possible. Donation after circulatory death (DCD) in Australia and New Zealand can occur after a decision has been made to withdraw treatment because it is considered no longer to be in the person’s best interest.4 This decision is usually reached by the healthcare staff and family, although in very rare and exceptional circumstances the decision may be made by the conscious, competent patient. The majority of patients suitable for DCD are receiving mechanical ventilation and/or other cardio-respiratory supportive treatments in intensive care units. If cardiac standstill, and thus death, occurs within a short timeframe after withdrawal of cardio-respiratory supportive treatment (generally within 60 to 90 minutes), donated organs can be transplanted with successful outcomes. Situations where DCD is considered include severe brain injury that has not and is not likely to progress to brain death, end-stage cardio-respiratory or other organ failure, high spinal cord injury, and progressive neuro-muscular conditions. Donation after Circulatory Death gives individuals and their families the opportunity to donate organs when brain death hasn’t occurred, and provides additional organs for transplantation to the community. Currently, donors following a DCD pathway comprise about 30% of organ donors in Australia and 16% of organ donors in New Zealand.6 There are, on average, fewer organs transplanted per donor via a DCD versus a DBD pathway, given the narrower organ suitability criteria that are applied in the situation of DCD. Currently, approximately 30% of planned DCD does not proceed to organ retrieval because death does not occur within the required time frames from withdrawal of cardio-respiratory support.7 The number of potential DCD donors is uncertain and there may be scope for further increase in donation via this pathway. 2.1.3 Retrieval surgery Each jurisdiction has processes in place to identify teams to undertake the surgical retrieval of abdominal or thoracic organs that have been assessed to be suitable for transplantation. Key team members from cardiothoracic, liver or renal transplant units who will travel to the donor hospital may include surgeons, cardiac anaesthetists and perfusion technicians. Team members from the local hospital include theatre nursing staff, operating theatre technicians, anaesthetists and, sometimes, surgical assistants. The donation specialist coordinator also attends the retrieval surgery to assist with logistic arrangements, documentation of the process, and care of the deceased post donation. At surgical retrieval, organs are further assessed for suitability by retrieval surgeons in consultation with transplant surgeons and physicians. This may at times require adjunctive information such as the results of biopsies, which may not be available until after organ retrieval. Arrangements for the transportation of organs are made according to the organ type and whether organs are for local use or for transport interstate or between Australia and New Zealand. There must be a reasonable prospect of at least one organ being transplantable before making the decision to proceed to retrieval surgery. The rate of non-utilisation of retrieved organs is expected to be small but greater than zero, since the final assessment of organ suitability can only be made at surgical retrieval. 2.2 Deceased donor and organ assessment 2.2.1 General evaluation of deceased organ donors Organ suitability for transplantation is determined by the answers to two questions: (i) is the donor medically suitable to donate any organ, and (ii) is a particular organ suitable for transplantation. Transplantation inevitably carries a small potential risk of transmission of infection or cancer from the donor to the recipient.8 That risk may vary depending on the organ and is assessed by considering donor risk factors April 2021 version 1.5 8 and by testing the donor. Donor-derived disease transmission complicates less than 1% of all transplantation procedures (excluding Cytomegalovirus [CMV] and Epstein-Barr virus [EBV]) but can result in significant morbidity and mortality.9,10 While it is possible to quantify risks through screening and testing, the risks of transmission of infectious and other diseases cannot be completely eliminated. The level of risk of disease transmission must be balanced against the risks to an individual patient of not proceeding with transplantation. The medical urgency of transplantation for some patients may mean that transplantation with an organ from a donor with increased risk of disease transmission is considered. Particularly where transplantation is life saving, an increased risk of disease transmission may be regarded as acceptable to the recipient. Conversely, where