Human 'suspended animation' trials begin
02:27 - Source: CNN

Story highlights

Medical researchers are experimenting with a process called induced hypothermia

They cool trauma patients' bodies down by pumping them with chilled saline solution

This wards off the potential damage caused by loss of blood and oxygen

It buys doctors more time to get patients into surgery

CNN  — 

As fans of “Grey’s Anatomy,” “ER” and any other hospital-based show can tell you, emergency-room doctors are fighting against time.

“When patients have bled so much that the heart stops, we know that we have very little chance of saving them,” said veteran trauma surgeon Samuel Tisherman. Even with breathing tubes, IVs and emergency chest surgery, fewer than one in 10 of such patients survive, he said. “The outcomes are pretty dismal.”

But Tisherman and a handful of other doctors may have found an innovative way to beat these grim odds.

He and his researchers are experimenting with something called induced hypothermia, or cooling trauma patients’ bodies to ward off the potential damage caused by loss of blood and oxygen. Because it causes the patient’s cell activity to shut down, this method essentially places the person in a sort of temporary limbo – not dead, but not fully alive, either – as a way of buying surgeons more time.

“Some people, including us early on … have called this idea ‘suspended animation.’ And in some sense, that’s true,” said Tisherman, who is spearheading a new clinical trial at the UPMC Presbyterian Hospital in Pittsburgh, Pennsylvania.

“But it’s important to recognize that these patients are not dead. We’re trying to save them still,” added the doctor. “What we’re doing is using science to try to come up with a new way to save people who are dying in front of us.”

Tisherman will oversee the trial despite leaving UPMC recently for a similar post at the Maryland Shock Trauma Center in Baltimore. Asked to define what he does, he prefers the more precise but unwieldy term, “emergency preservation and resuscitation,” or EPR.

The process works like this: Doctors insert a tube into the trauma patient’s aorta and pump in a large amount of ice-cold saline solution to cool the core of the body as quickly as possible to about 50 to 55 degrees.

At normal body temperatures, cells need a regular oxygen supply. When the heart stops, blood no longer carries oxygen throughout the body, and the brain can only survive for a few minutes.

At these reduced temperatures, however, tissue cells need less oxygen because all chemical reactions slow down. It’s the same principle that has allowed some people to survive near-drownings in cold water, despite being submerged for a half-hour or more.

The induced hypothermia, or “suspended animation,” process is expected to buy doctors enough time – at least 45 minutes – to get patients into the operating room, hook them up to machines to restart their circulation, warm them up and then restore their blood.

The groundbreaking process has proven successful in animal trials involving pigs. Now Tisherman and his researchers plan to carry out a similar trial with humans, comparing 10 patients who get EPR with 10 who don’t. The patients will have suffered cardiac arrest after a traumatic injury and have little chance of survival under normal circumstances.

The federal government is watching with interest. Tisherman said the Food and Drug Administration is overseeing the trial, and the Department of Defense, which sees potential for treating soldiers in the field, has contributed funding.

It will take several years to complete the trial and crunch the data. Tisherman’s hope is to eventually prove the process works and help it spread to other trauma centers around the world.

“As trauma surgeons, we’re always fighting against the clock. And we’ve all seen people who had injuries we could fix if we just had a few more minutes. It’s heartbreaking when these patients don’t make it,” he told CNN.

“We find it exciting that this might give us a way to save people that we otherwise can’t.”