Cautious nod
In a 2022 consensus statement, the International Society for Heart and Lung Transplantation (ISHLT) gave a cautious nod toward DCD and NRP, dependent on local recommendations.
The ISHLT conclusion reads: “With appropriate consideration of the ethical principles involved in organ donation, DCD can be undertaken in a morally permissible manner. In all cases, the introduction of DCD programs should be in accordance with local legal regulations. Countries lacking a DCD pathway should be encouraged to develop national ethical, professional, and legal frameworks to address both public and professional concerns.”
The author of a recent editorial on the subject, Ulrich P. Jorde, MD, head of the heart transplant program at Montefiore Medical Center, New York, said, “DCD is a great step forward. People regularly die on the heart transplant waiting list. DCD will increase the supply of donor hearts by 20% to 30%.”
However, he noted that while most societies have agreed on a protocol for organ donation based on brain death, the situation is more complicated with circulatory death.
“Different countries have different definitions of circulatory death. How long do we have to wait after the heart has stopped beating before the patient is declared dead? Most countries have agreed on 5 minutes, but other countries have imposed different periods and as such, different definitions of death.
“The ISHLT statement says that restarting the circulation is acceptable if death has been certified according to prevailing law and surgical interventions are undertaken to preclude any restoration of cerebral circulation. But our problem is that different regional societies have different definitions of circulatory, death which makes the situation confusing.”
Dr. Jorde added: “We also have to weigh the wishes of the donor and their family. If family, advocating what are presumed to be the donor’s wishes, have decided that DCD would be acceptable and they understand the concept and wish to donate the organs after circulatory death, this should be strongly considered under the concept of self-determination, a basic human right.”
Variations in practice around the world
This ethical debate has led to large variations in practice around the world, with some countries, such as Spain, allowing both methods of DCD, while Australia allows direct procurement but not NRP, and Germany currently does not allow DCD at all.
In the United States, things are even more complicated, with some states allowing NRP while others don’t. Even within states, some hospitals and transplant organizations allow NRP, and others don’t.
David A. D’Alessandro, MD, cardiac surgeon at Massachusetts General Hospital, Boston, uses only the direct procurement approach as his region does not allow NRP.
“The direct procurement approach is not controversial and to me that’s a big advantage. I believe we need to agree on the ethics first, and then get into a debate about which technique is better,” he told this news organization.
Dr. D’Alessandro and his group recently published the results of their study, with direct procurement DCD heart transplantation showing similar short-term clinical outcomes to DBD.
“We are only doing direct procurement and we are seeing good results that appear to be comparable to DBD. That is good enough for me,” he said.
Dr. D’Alessandro estimates that in the United States both types of DCD procedures are currently being done about equally.
“Anything we can do to increase the amount of hearts available for transplantation is a big deal,” he said. “At the moment, only the very sickest patients get a heart transplant, and many patients die on the transplant waiting list. Very sadly, many young people die every year from a circulatory death after having life support withdrawn. Before DCD, these beautiful functional organs were not able to be used. Now we have a way of saving lives with these organs.”
Dr. D’Alessandro noted that more and more centers in the United States are starting to perform DCD heart transplants.
“Not every transplant center may join in as the DCD procedures are very resource-intensive and time-consuming. For low-volume transplant centers, it may not be worth the expense and anguish to do DCD heart transplants. But bigger centers will need to engage in DCD to remain competitive. My guess is that 50%-70% of U.S. transplant centers will do DCD in future.”
He said he thinks it is a “medical shortcoming” that agreement cannot be reached on the ethics of NRP. “In an ideal world everyone would be on the same page. It makes me a bit uncomfortable that some people think it’s okay and some people don’t.”
Adam DeVore, MD, a cardiologist at Duke University Medical Center, Durham, N.C., the first U.S. center to perform an adult DCD heart transplant, reported that his institution uses both methods, with the choice sometimes depending on how far the heart must travel.
“If the recipient is near, NRP may be chosen as the heart is transported on ice, but if it needs to go further away we are more likely to choose direct procurement and use of the OCS box,” he said.
“I am really proud of what we’ve been able to do, helping to introduce DCD in the U.S.,” Dr. DeVore said. “This is having a massive benefit in increasing the number of hearts for donation with great outcomes.”
But he acknowledged that the whole concept of DCD is somewhat controversial.
“The idea of brain death really came about for the purpose of heart donation. The two things are very intricately tied. Trying to do heart donation without brain death having been declared is foreign to people. Also, in DCD there is the issue of [this]: When life support is removed, how long do we wait before death can be declared? That could be in conflict with how long the organ needs to remain viable. We are going through the process now of looking at these questions. There is a lot of variation in the U.S. about the withdrawal of care and the declaration of death, which is not completely standardized.
“But the concept of circulatory death itself is accepted after the withdrawal of life support. I think it’s the rush to take the organs out that makes it more difficult.”
Dr. DeVore said the field is moving forward now. “As the process has become more common, people have become more comfortable, probably because of the big difference it will make to saving lives. But we do need to try and standardize best practices.”
A recent Canadian review of the ethics of DCD concluded that the direct procurement approach would be in alignment with current medical guidelines, but that further work is required to evaluate the consistency of NRP with current Canadian death determination policy and to ensure the absence of brain perfusion during this process.
In the United Kingdom, the definition of death is brain-based, and brain death is defined on a neurological basis.
Dr. Stephen Large from Papworth explained that this recognizes the presence of brain-stem death through brain stem reflex testing after the withdrawal of life support, cardiorespiratory arrest and 5 further minutes of ischemia. As long as NRP does not restore intracranial (brainstem) perfusion after death has been confirmed, then it is consistent with laws for death determination and therefore both direct procurement and NRP are permissible.
However, the question over possible collateral flow to the brain has led the United Kingdom to pause the NRP technique as routine practice while this is investigated further. So, at the present time, the vast majority of DCD heart transplants are being conducted using the direct procurement approach.
But the United Kingdom is facing the bigger challenge: national funding that will soon end. “The DCD program in the U.K. has been extremely successful, increasing heart transplant rates by up to 28%,” Dr. Berman said. “Everybody wants it to continue. But at present the DCD program only has national funding in the U.K. until March 2023. We don’t know what will happen after that.”
The current model in the United Kingdom consists of three specialized DCD heart retrieval teams, a national protocol of direct organ procurement and delivery of DCD hearts to all seven transplant programs, both adult and pediatric.
If the national funding is not extended, “we will go back to individual hospitals trying to fund their own programs. That will be a serious threat to the program and could result in a large reduction in heart transplants,” said Dr. Berman.