A Pittsburgh hospital is set to test suspended animation in some gunshot and stabbing victims — a last ditch effort to buy them more time.
The groundbreaking trial, which borrows from science fiction, could start as early as next week after a three-years-long approvals process.
“We just want to review everything one more time,” said trial leader Dr. Samuel Tisherman, professor of critical care medicine at the University of Pittsburgh Medical Center. “Our main goal is to show that it can work, so we want to be selective about the patients we enroll.”
Those patients will be victims of fatal gunshot and stabbing wounds whose hearts have stopped beating en route to the hospital.
“The standard of care at that point is to intubate them, give them fluids and blood and open up the chest,” said Tisherman. “If you quickly find something you can fix in there, like a source of bleeding that you can stop, then there’s a chance of survival. But if you don’t, that’s when we’ll switch to EPR.”
EPR, or Emergency Preservation and Resuscitation, will swap what little blood the patient has left for cold saltwater, dropping their temperature to 50 degrees and putting vital cellular functions on ice.
“As you get colder, you don’t really need red blood cells,” Tisherman said, explaining that chilly cells use small amounts stored oxygen and glucose to stay alive. “Then the trauma surgeons have more time to find the problem.”
If they find the problem, they’ll scurry to fix it. They have less than an hour from the start of the freeze until “reperfusion” – a process that fills the body back up with blood.
“The surgeon will only do what he or she absolutely has to do,” said Tisherman. “Little things can get done later.”
The trial will test EPR in 10 patients and compare the results to 10 uncooled controls, a protocol the U.S. Food and Drug Administration approved under an “exception from informed consent” provision that allows “urgent intervention” – even if it’s experimental – for life-threatening conditions.
Fewer than 8 percent of patients survive traumatic cardiac arrest, a 2006 study found.
The new trial will take careful coordination between emergency department staff, trauma surgeons, cardiac surgeons and perfusionists, Tisherman said.
“Enrollment has to be done basically at a moment’s notice,” he said, adding that three trauma surgeons have been trained to recognize candidates for the procedure. “If one of them is in the building and the right person comes along, then we can go ahead.”
Patients who arrive when none of the trained trauma surgeons are in the building will serve as controls, Tisherman said. The trial is expected to take two years.