It’s a staple of countless science fiction movies: the crew of a deep space faring vessel has a long trip ahead of them: So rather than lounging about inside the cramped quarters of their ship for months or years, they climb into machines that place them in a state of suspended animation, effectively freezing them in time until they reach their intended destination.

Like warp drives and photon torpedoes, it’s easy to assume that humanity is still a long way off from being able to accomplish such a feat, but — as seems to be the case more and more often in recent years — the future has already arrived.

Doctors at the University of Maryland Medical Center recently announced that they have successfully placed a human being into a state of suspended animation for the first time — though their goals are much more down to earth than the uses this sort of tech sees in movies like “Aliens.”

Instead of freezing humans for long duration trips, these doctors are trying to save trauma patients in the emergency room. The process is called Emergency Preservation and Resuscitation (EPR), and doctors are using it to stop seriously injured humans from dying before they’re able to provide the necessary life-saving care.

Gunshot and stabbing victims, for instance, that have already lost a great deal of blood and are on the verge of death, can be placed in a state of suspended animation thus allowing the medical staff the time they need to save them. This sort of technology would have obvious implications in combat or in the aftermath of terror attacks in particular, but could see widespread use around the world in communities that aren’t close to trauma centers.

Of course, conducting this sort of testing comes with a number of complex rules and protocols that must be followed (in other words, the doctors aren’t just asking for volunteers). The testing is conducted when a trauma patient arrives with a low-likelihood of surviving their injuries. In such a case, doctors are justified in attempting such an experimental procedure in their attempt to save them.

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The process starts when doctors believe a patient is literally within minutes of dying, so they give the order to rapidly replace the patient’s blood with ice-cold saline. This process rapidly reduces the body temperature down to around 50 or 60 degrees, which stops the heart and any measurable brain activity. If it weren’t for the doctors’ ability to revive a patient from this state, the process would seem an awful lot like death.

Because of the complicated ethics issues involved, Dr. Samuel Tisherman, at the University of Maryland, has been trying to get approval to conduct human trials for over five years, after having spent the majority of his career specializing in the concept of suspended animation. Even when working with patients that are almost or already clinically dead, there remain a number of obstacles to navigate through as there are FDA-established rules regarding the use of experimental medicine on those who aren’t capable of giving informed consent.

And there are still serious risks associated with the procedure that will need to be studied and mitigated before EPR can become a common facet of any medical facility — or starship. One of them, for example, is reperfusion injury, which is something that can happen when the body reacts negatively to the reintroduction of blood into the system. Reperfusion injury is just one of a number of issues associated with the EPR process, which may require drugs to mitigate and further testing to assess.

For now, EPR may be a significant leap ahead in medical science, but it’s still a long way off from finding its way into local emergency rooms.