Proof that process of death can be reversed as pig’s organs brought back to life

Pig - iStockphoto
Pig - iStockphoto

The process of death can be reversed, scientists have shown, by bringing a pig’s organs back to full health after it was killed.

Yale scientists have developed a way to reverse the biological process of dying, where organs break down and stop working after the heart stops beating.

The breakthrough could revolutionise transplantation by giving doctors more time to harvest organs. It could also be used to treat seriously injured patients in the future.

A dead pig was hooked up to a machine called OrganEx one hour after an induced cardiac arrest.

The machine pumps a fluid containing 13 different compounds around the body which staves off organ death and allows the cells to flourish, even after the animal is dead.

Dying organs treated with the new technology were shown to recover and improve to the point of being comparable to those of a living pig.

'Cascade of dominoes'

After death, when the brain dies and the heart stops pumping on its own, oxygen levels drop and there is “a cascade of dominoes” that damages and eventually kills organs.

“All cells do not die immediately, there is a more protracted series of events,” said Dr David Andrijevic, associate research scientist in neuroscience at Yale School of Medicine and co-lead author of the study.

“[OrganEx] is a process in which you can intervene, stop and restore some cellular function.”

Dr Zvonimir Vrselja, a co-author, added: “Under the microscope, it was difficult to tell the difference between a healthy organ and one which had been treated with OrganEx technology after death.”

While the technology is effective at improving function, it does not rekindle the essence of life, the scientists said, as there was no evidence of electrical activity in the brain after death.

It builds on a 2019 study where a smaller version of the technology, called BrainEx, repaired neurons in pig brains, although no electrical activity was detected.

“This is a truly remarkable and incredibly significant study,” said Dr Sam Parnia, associate professor of critical care medicine at New York University, who was not involved with the project. “It demonstrates that after death, cells in mammalian organs (including humans) such as the brain do not die for many hours.

“This study demonstrates that our social convention regarding death, ie as an absolute black and white end, is not scientifically valid. By contrast, scientifically, death is a biological process that remains treatable and reversible for hours after it has occurred.”

The potential of the technology is vast, and the team is cautious that it must be used ethically. There is no reason to believe, they said, that the technology can be used to reverse ageing or revive people after the point of death.

Its primary use will be to extend the healthy lifespan of cadavers to enable fitter, healthier organs to be offered up for transplant.

'Far away from use in humans'

In the future, it could also be used on patients who have suffered extreme injuries where their blood flow has been interrupted, such as after strokes, drowning or trauma.

“This is very far away from use in humans,” said Dr Stephen Latham, study co-author and director of the Yale Interdisciplinary Centre for Bioethics.

“The goal here was to see whether the use of [OrganEx] could restore metabolic and cellular function across a wide range of organs and we've discovered that it can, but it doesn't restore all function in all organs.

“We'd need to study in a lot more detail the degree to which damage is undone in different kinds of organs before we can be even close to thinking about trying an experiment like this on a human being who had suffered anoxic damage.”

Dr Anders Sandberg, a senior research fellow at Oxford University, was not involved with the research but added that the use of the machine for organ donation was “unproblematic good news”.

However, he warned its applications for living people mean it could prevent people from dying rather than making them recover.

“There is a challenging ethical issue in determining when radical life support is just futile, and as technology advances we may find more ways of keeping bodies alive despite being unable to revive the person we actually care about,” he said.

The research is published in Nature.