Health and Medicine

Suspended Animation Human Trials About to Begin

May 26, 2014 | by Lisa Winter

Photo credit: Army Medicine via flickr

With traumatic injuries, timing in treatment can be the difference between life and death. What if surgeons could hit the pause button, giving them precious additional time to treat the wounds? Suspended animation has been featured in a wide array of fictional films, but could it actually work on humans? The FDA has approved a small study that will allow surgeons at UPMC Presbyterian Hospital in Pittsburgh to try to suspend human life later this month. 

In Hollywood, suspended animation involves freezing solid (or nearly so), thawing at some point in the future when new medical advances have taken place to treat their conditions. This emergency preservation and resuscitation (EPR) technique isn’t quite so extreme, but it will reduce body temperature to 10 degrees Celsius (50 degrees Fahrenheit) by inserting a cannula into the aorta and flushing cold saline into the system. This will slow the blood flow, which will prevent the body from bleeding out (which can be fatal within minutes). The low temperatures will also slow other biological processes as well. 

This state of hypothermia can only be sustained by the human body for about two hours. While this isn’t as dramatic of EPR as some may have expected, that could easily provide enough time for surgeons to perform emergency lifesaving surgery. Trauma patients who suffer cardiac arrest have a 7% chance of survival, giving this technique some very real and amazing implications.

Peter Rhee first tried this technique on 40 pigs in 2000, with the results published in 2006. After inflicting a lethal wound to simulate real-world trauma scenarios, the pigs were cooled down so the surgeons could operate then resuscitate them. While all of the control pigs died, the surgeons were able to save 90% of the pigs. None of the surviving pigs were reported to have sustained cognitive or physical impairment.

Due to the extremely time-sensitive and dire nature of the injuries of the test subjects, the FDA has declared that the surgeons will not require informed consent. As a precaution, the team took out advertisements to inform the public of the upcoming study, and even set up a website that would allow people to opt out, if desired. As of yet, nobody has opted out.

The team will first use this technique on 10 trauma patients whose injuries would be otherwise fatal. That group will be compared against 10 other patients who are not able to undergo EPR, due to the surgical team not being available. After the first increments of 10 EPR and 10 control patients, the technique will be analyzed and refined. They will continue in this fashion until enough data points have been collected which will allow them to analyze the efficacy of suspending life in this manner, though a predetermined set number has not been made.

 

[Header image “US Military doctors perform surgery on Iraqi soldier” via Army Medicine on flickr used in accordance with CC BY 2.0]

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