51成人动漫

With little attention or debate, transplant surgeons across the country are experimenting with a kind of partial resurrection: They're allowing terminal patients to die, then restarting their hearts while clamping off blood flow to their brains. The procedure allows the surgeons to inspect and remove organs from warm bodies with heartbeats.

Transplant surgeons and several bioethicists argue that the procedure is appropriate and crucial to boosting the number of organs that are available for transplant. But critics -- including other bioethicists and the nation's second-largest physician organization -- warn that surgeons are trampling the line between life and death.

"We're so hungry for organs right now that we are pushing all the limits," Wes Ely, MD, MPH, a critical care physician and transplant pulmonologist at Vanderbilt University, told 51成人动漫. "I just want us to be super-cautious. We need to press the pause button on this and have some more conversations so that we can set up boundaries and stay in the right lane. The dignity of the human who donates organs should never be sacrificed."

The American College of Physicians (ACP), which represents primary care doctors, is also a critic. It warned in a 2021 statement that the procedure raises "profound ethical questions regarding determination of death, respect for patients, and the ethical obligation to do what is best."

Proponents, however, are eagerly moving ahead with the procedures, known as normothermic regional perfusion with controlled donation after circulatory death (NRP-cDCD). Three hospitals in , , and are currently investigating the procedure in clinical trials. Several others have adopted it too, Amy Fiedler, MD, a cardiac and transplant surgeon at the University of California San Francisco, told 51成人动漫.

"It's expanding rapidly," said Fiedler, who has performed several of the procedures. "Every time I talk to colleagues, they want to talk about how to build an NRP program and get it started."

Declaration of Death, Then a Heart Restart

Surgeons first transplanted organs in 1954, and this year the United Network for Organ Sharing (UNOS) celebrated a in the U.S. since then. The highest number of annual transplants was more than 40,000 in 2021.

Most organ donors are "deceased," as UNOS puts it. How they get to that point is the crux of the debate over the partial-resurrection procedures.

In the organ-retrieval procedures that are most well-known, patients are declared brain dead but they remain on life support: Their hearts beat, their lungs breathe. Surgeons remove organs for transplantation, and then the life support system is turned off.

But there's another category of organ donor: A patient who cannot survive without life support, but is not brain dead -- someone with severe brain injury, for instance, who has no chance of recovery.

In the past, transplant surgeons wouldn't remove organs until the hearts of these patients stopped for good. Now, transplant surgeons have changed the game.

An NRP-cDCD transplant of a heart -- or another organ such as the liver -- works like this: Consent is obtained to retrieve organs from the patient. The life support is withdrawn, and – if all goes according to plan – the patient's heart stops.

"A dying process of up to thirty minutes of agonal phase can be tolerated," cardiac surgeons from Vanderbilt University explained in published earlier this year.

Then there's a "stand-off" period of a few minutes to see if the patient revives. If not, the patient is declared dead, and the surgical team gets to work.

"The donor's arch vessels are clamped to exclude cerebral perfusion, and the donor is cannulated" prior to being attached to a bypass machine, the Vanderbilt report explains. "The typical period from incision to establishing extracorporeal flow is three to five minutes. Perfusion is continued for forty-five minutes, after which the organs are harvested in the usual manner."

In other words, once the patient is declared dead, the blood flow to the brain is shut off. Then the heart is restarted with the help of a bypass machine, and organs are examined and removed within 45 minutes.

The 'Dead Donor Rule'

The 160,000-member ACP, the second-largest U.S. physician group after the American Medical Association, has raised the loudest alarm about the NRP-cDCD procedure. In a , the organization warned that it "raises significant ethical concerns and questions regarding the dead donor rule, fundamental ethical obligations of respect, beneficence, and justice, and the imperative to never use one individual merely as a means to serve the ends of another, no matter how noble or good those ends may be."

Matthew DeCamp, MD, PhD, a bioethicist at the University of Colorado and a consultant to ACP, was lead author of a in the journal Chest opposing the procedure.

"You're reversing the conditions under which death is declared and taking active steps to ensure the progression to brain death," he told 51成人动漫. "The person is declared dead, and the subsequent actions invalidate that declaration."

DeCamp said this process bumps into the dead donor rule, an ethical standard within transplant medicine that says the process of retrieving an organ cannot kill a donor. However, the withdrawal of life support with consent, essentially facilitating a death, is allowed.

"The dead donor rule is ethically foundational to organ transplantation. It's the idea that medicine looks out for the best interests of the patients -- do no harm -- and acts cannot be taken that would cause death," DeCamp said. "Resuscitating the patient and reversing those conditions engages with the ethics of the dead donor rule."

He added: "Imagine you're an outside observer watching this procedure take place. You'd be unable to distinguish whether it was proceeding to organ transplantation or the resuscitation of the patient."

Anyone can watch the procedure in from Vanderbilt University.

Time to Update the Legal Definition of Death?

Arthur Caplan, PhD, of New York University and perhaps the most widely known and quoted bioethicist in the U.S., and his colleagues defended the NRP-cDCD procedure earlier this year.

"Its benefits far outweigh the addressable ethical considerations raised against the practice," they wrote in an American Journal of Transplantation .

The purpose of the procedure is crucial, lead author and NYU bioethicist Brendan Parent, JD, told 51成人动漫. "We are perfusing the heart again, we are not resuscitating the heart. That's a critical language distinction. Any time a heart has stopped, technology has made it possible to restart it at least a little bit. So we cannot hang the definition of death on whether it's restartable. Instead, we need to ask, why are we restarting the heart?"

Parent also emphasized that while state laws that define death require "irreversible" cessation of brain or circulatory function, that doesn't mean death can only be declared when there's absolutely, positively no chance that a patient could be revived. If the law was actually that strict, "then very, very few people could ever actually legally be called dead," said Parent, who also co-wrote responding to DeCamp and colleagues.

Still, Parent and colleagues believe that it's "time to update the legal definition of death," as they put it in the American Journal of Transplantation commentary, "to recognize the current ethical practice. Death can be declared when circulation has stopped permanently. Permanent cessation is when circulation has stopped on its own and there will be no attempt to restart it."

What should happen while the law tries to catch up?

"This should just stop now," said Alexander Capron, LLB, a law professor at the University of Southern California. (LLB refers to a law degree.)

Like Ely, he wants to pause the process that's allowed the NRP-cDCD procedure to become routine.

Capron told 51成人动漫 that he believes that the procedure isn't necessary, may turn the public against organ transplantation, and could lead to prosecutions against physicians for violating state laws that require "irreversible" cessation of brain or circulation/respiratory activity.

, for instance, uses standard language that states that "an individual who has sustained either (1) irreversible cessation of circulatory and respiratory functions, or (2) irreversible cessation of all functions of the entire brain, including the brain stem, is dead. A determination of death must be made in accordance with accepted medical standards."

When the heart is restarted in the NRP-cDCD procedure, "these bodies are called dead, but they have circulation," Capron said. "The law says 'irreversible' cessation of circulatory and respiratory function. That isn't what's happening. [Circulation] is not irreversible, it's present."

Capron predicted that the which advises states about laws such as , will balk at the procedure. "They are likely to see this as a slippery slope and not want to allow it," said Capron, a former executive director of the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research.

But any such effort will face stiff opposition from transplant surgeons and organ transplant advocates. They'll argue that NRP-cDCD transplants are safe and necessary to protect donated organs and increase their supply.

A found that NRP-cDCD "reduces certain post-transplant complications, though this finding is not universal." Another study from 2021 reported that transplanted adult hearts removed after circulatory death fared about as well as those removed following brain death. The study authors wrote that if the hearts of all potential donation after circulatory death donors were inspected via echocardiograms, the number of heart transplants in the U.S. might rise by 300 a year.

Forging a Way Forward

Is there a way to allow NRP-cDCD procedures while addressing the concerns of critics? Ely said it would help if the procedures mandated a check of whether patients are truly brain dead after the heart stops beating when life support is withdrawn.

"There needs to be no question that we didn't create brain death by clamping their vessels [before restarting the heart]. We want to make sure we're not taking organs from people who have working neurons," said Ely, who wrote the widely praised "Every Deep-Drawn Breath: A Critical Care Doctor on Healing, Recovery, and Transforming Medicine in the ICU."

Fiedler said this perspective isn't reality-based. "When a patient dies of circulatory death in the intensive care unit, there's no testing to say that that patient is dead either. It's simple, the declaration of death by a physician."

For now, all eyes are on the Uniform Law Commission, which with pressure to bring clarification to confusion among state laws over how to measure brain death. Meanwhile, NRP-cDCD procedures, already common in Europe, appear to be on the rise in the U.S.

According to a , organ donations after circulatory death -- not in patients who were originally brain dead -- have grown from 1,883 in 2017 to 3,224 in 2020. Over that same time period, organ donations after brain death grew at a slower rate, from 8,403 to 9,364.

More donated organs, of course, benefit more people. Thoracic surgeon Deane Smith, MD, of New York University, told 51成人动漫 there are other people to consider -- the loved ones of donors. The NRP-cDCD procedure "really maximizes the potential difference these families may be able to make," he said, "and by and large, that's what the family is looking for."

Fiedler agreed and highlighted the value of organ donations of the heart, which can "hold special value."

"It's a very, very positive experience when a patient's heart is able to be transplanted successfully," she said. "As long as [the procedure] is explained to the families and they agree with it, which in large part they do, it's largely a positive for the transplant community."

Correction: This article previously identified Alexander Capron as the former executive director of the Uniform Law Commission. He is the former executive director of the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research.

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