Doctors are set to recreate a sci-fi technique as they begin suspended animation by freezing trauma victims in the hope of keeping them alive.
The technique will be used on ten patients who would otherwise be expected to die from their wounds, which will likely come from stabbings or shootings. The doctors on the project will be paged when a patient is likely to fit the procedure. There is around one such case every month, and they have a survival rate of less than 7 per cent.
Doctors will begin by removing patients’ blood. Their body temperature will then be lowered to around 10 degrees Centigrade by pumping a large volume of cold fluid through a tube placed in the aorta, the largest artery in the body. After the process is complete patients will be clinically dead.
To resuscitate them, doctors will use a heart-lung bypass machine to restore blood circulation.
"We are suspending life, but we don't like to call it suspended animation because it sounds like science fiction," Samuel Tisherman, the surgeon who is leading the trial, told the New Scientist. "So we call it emergency preservation and resuscitation."
The procedure will happen at UPMC Presbyterian Hospital in Pittsburgh, Pennsylvania in the US.
Because the patients will be unable to give consent to the procedure, researchers will instead run a publicity campaign to allow potential patients to opt out. Locals will be able to order bracelets to indicate that they don’t consent.
The outcome of the ten initial patients will be compared with ten other patients that could not receive the procedure. Doctors then hope to refine the technique.
Patients will only be cooled down for a few hours, but doctors hope that will be enough to save the patients from losing too much blood. Doctors already use cool down parts of patients’ bodies to stop blood flow and perform surgery.
The technique has been successfully used on pigs. In experiments, scientists simulated gunshot wounds by inducing fatal wounds in the animals and simulating medical procedure. While all the pigs that weren’t cooled died from the wounds, 90% of pigs that were cooled at a medium rate survived. The surviving pigs had no long-term physical or cognitive problems.
At lower temperatures, cells need less oxygen because chemical reactions slow down. Similar effects to the techniques have been seen in some accidents, where climbers and skiers have fallen into cold water and entered the state by accident.