American surgeons have plunged a man into a state of artificial hibernation(suspended animation), according to the journal New Scientist. To do this, his blood was completely replaced by a cold (10-15 degrees) saline solution. This method allows you to buy time for emergency surgery for severe blood loss and cardiac arrest. However, it is not yet known whether the patient was successfully operated on.

By hibernation, hibernation usually mean slowing down physiological processes in the body. Animals use it to survive an unfavorable season, most often – cold. At the same time, their body temperature can decrease to zero degrees. However, in this state animals cannot exist for a long time, and their hibernation is punctuated by periods of physiological “awakening” when they warm up from the inside.

Whether it is possible to immerse a person in such a state and how long he will be able to stay there without risk to health is not yet known, because no one has tried it. Until now, scientists have experimented only on model mammals. To achieve the effect of hibernation, the blood of animals was completely replaced by cold (10-15 degrees) saline solution. At this point, the work of many organs, including the brain, stopped. After the operation, the animals were warmed up and returned their own blood. A team of doctors from the University of Maryland School of Medicine tested this method on pigs and found that pigs are capable of experiencing three hours of hibernation, after which they can be returned to a normal life.

Researchers have long stated their intention to test this method on a person. Doctors have already received approval from the FDA (the US Food and Drug Administration), and they were even allowed to select patients without informed consent. This is a justifiable measure: People who may need a hibernation are admitted to hospital unconscious after being shot or stabbed, and they are not able to give consent. At the same time, we are talking about their lives, because doctors in this situation have a few minutes to stabilize the patient and less than 5% survive after that. Hibernation should increase the time to save the patient up to two hours.

And to do this, doctors planned to test their method on 10 patients after the approval from the FDA. As a control group, they were going to use 10 people who would be admitted to the hospital with similar injuries outside the working hours of their normal shift and therefore, would be operated by other doctors according to the standard protocol. The doctors planned to present the test results at the end of 2020.

At a conference of the New York Academy of Sciences, Samuel Tisherman from the University of Maryland School of Medicine said that his team of doctors performed the first operation on a patient in the hibernation state (also knows as “suspended animation”).” Tischerman did not specify exactly how many patients had already been through the trial, and did not say anything about the effects of the surgery. However, he claimed that his team was able to immerse the patient in a hibernation state, which the researchers themselves were pleasantly surprised.

It is too early to talk about the results of the experiment, but we already know where to expect trouble. Cell cultures sometimes develop lesions or damage during “return to life.” Researchers have not yet been able to say anything about their causes, but have already noticed that the longer the cell has gone without oxygen, the more chemical reactions with toxic products begins after it is submitted. If the first human trials are successful, doctors will have to find drugs that could minimize the harm from “warming”.