A new method for harvesting hearts from organ donors has sparked debate about the surprisingly blurred line between life and death in hospitals – and whether donors may experience some level of consciousness or pain while their organs are harvested.
The new method has been distributed to major hospitals in New York City and beyond. In 2020, it became the first hospital in the United States to try the new method, according to NYU Langone Health in Manhattan. But New York Presbyterian Hospital, which has the city’s largest organ transplant program, rejected the technique after an ethics committee there investigated the case.
If widely accepted, the method could significantly increase the number of hearts available for transplant, saving lives.
That’s because most heart donors now come from a low-death category: donors who are known to be brain dead after a traumatic event, such as a car accident. But they remain on life support – their hearts beating and blood circulating, bringing oxygen to their bodies – until the transplant team recovers their organs.
Transplant surgeons say the new technique will vastly expand the pool of patients who end up in comas, brain-dead, and whose families are off life support because they have little chance of survival. It is said that these patients died after their heart stopped. But hearts never recover from these donors because they are often damaged by lack of oxygen during the dying process.
Surgeons have found that restoring blood flow to the heart at a remarkable rate makes it suitable for transplantation.
But two aspects of the process made some surgeons and bioethicists uncomfortable.
Some ethicists and surgeons say the first problem stems from the way death is commonly defined: the heart stops and circulation is irrevocably stopped. Critics say the new procedure, which involves restarting blood circulation, invalidates the previous declaration of death.
But this may be a minor problem compared to the next step surgeons take: They use metal clamps to cut off blood flow from the regenerated heart to the donor’s head, limiting blood flow to the brain to prevent any brain activity from being restored. Some physicians and ethicists see this as a tacit admission that the donor may not be legally dead.
“It’s an embarrassing thing to do,” longtime heart surgeon and transplant specialist Dr. V. Eric Thomson said at a recent panel discussion about the procedure at Yale School of Medicine.
As a legal matter, there are two different ways to determine whether a person is dead. In addition to circulatory death, there is also brain death.
The new set of donors, on the contrary, come from the first category and are not brain dead. If their eyeballs are touched, they still blink. If their trachea is removed, they can suffocate.
For them, death is not immediate: five minutes or 50 may pass after life support is withdrawn and a doctor says that circulation has stopped.
NU Langone used the new system, which uses a cardiopulmonary bypass machine, to recover about 30 hearts from such patients who failed to recover, said Dr. Nader Moazami, who oversaw the first procedure at the institution. Vanderbilt Medical Center in Nashville adopted the procedure, starting shortly after NY Langone, and has since done more.
But some medical groups opposed it. The American College of Physicians clamps arteries to the brain to confirm brain death while restarting blood flow It seems to violate “Deceased Donor Act” – the basic principle of organ transplantation in the United States to ensure that the procurement of organs in the United States does not cause the death of the donor.
Dr. Robert Trug, a bioethicist at Harvard Medical School who attended the Yale panel, said the new method holds great promise for expanding the number of donor hearts. But he felt the proponents were downplaying the ethical and legal problems.
“I’m a little concerned that there’s a little bit of gaslighting going on here with the public among some transplant experts,” Dr. Trugue said at a panel last month.
Dr. Moazami, the NYU Langone surgeon, said much of the criticism comes from ethicists who spend little time with patients stuck on transplant waiting lists.
“You guys can sit in your office worrying about the ethics of something, but you don’t have to walk into a room where a family is faced with a patient who is dying, waiting for an organ, and not going. To get an organ and that patient dies,” Dr. Moazami said in an interview. “If you’ve ever had an experience like this in your life, you’d never tell me that what I’m doing is unethical.”
The debate over the procedure — sometimes called NRP, for normothermic regional hemorrhage — echoes earlier medical and legal debates about how to determine death, when to distinguish the dead from the dead, and what doctors are allowed to do at the end. minutes.
Some experts are raising the bar.
“A large district attorney could plausibly argue that doctors following the NRP protocol did not permanently stop any brain function that would ensure the patient’s death,” said two transplant experts—Alexandra Glazier, a lawyer who runs an organ donation network throughout New England and bioethics at the University of Southern California. Alexander Kapron, an expert and professor, wrote in an opinion piece in the American Journal of Transplantation last year.
There are currently 103,327 people on the national transplant waiting list, with 17 people waiting each day. Most of them are waiting for kidney or liver.
Heart transplants are rare, with only about 3,500 performed each year. every year, About 20 percent Those on the list waiting for a new heart either die or are too sick to be removed from the list.
Scientific advances may one day ease the shortage of organs available for transplant. The solution may be genetically-modified pigs or organs Human organs growing in animals. Or maybe body parts Grown from scratch in the laboratory.
But until then, expanding the number of heart transplants requires the use of donor hearts.
A Massachusetts company, TransMedics, sells a machine to deliver oxygenated blood to the heart outside the body — avoiding the ethical debate. It is removed from the donor, the heart is inserted What does a Tupperware container look like?Blood circulates through it. But the tools can be expensive to use.
The NRP procedure is inexpensive. Dr. Moazami’s team first reported on January 20, 2020, a 43-year-old donor suffering from end-stage liver disease.
A toxic build-up in his body left him comatose. With the family’s consent, life support was withdrawn. Five minutes later, the man was gasping for breath. At 14 minutes his heart stopped. After 10 minutes, Dr. Moazami’s team cut open his chest, attached arteries to his brain, and began pumping blood through his body using a bypass machine—a device routinely used in heart surgeries.
Finally, the heart began to beat on its own. After half an hour, the surgeons removed it, and then implanted it.
Dr Moazami learned about the procedure from cases in England, where surgeons in Cambridge began testing it in 2015.
Dr. Moazami does not discount the ethical concerns of his critics. He pointed out that new scientific research has raised complex questions about what happens to the brain after death. Experiments conducted at Yale indicate the presence of certain cellular activity in the brains of dead pigs.
He said it’s important to place an artery in the brain as a measure to reduce the chance of loss of consciousness or signs of unconsciousness when blood circulation is restarted in the donor.
“The brain remains a ‘black box,'” said a team of ethicists and surgeons at NYU Langone, including Dr. Moazzam. He wrote last year.