Suspended animation: saving time on the way to deep space and the hospital

"Alien" (1979)

Suspended animation is a process where an organism’s physiological processes slow down to a point resembling death. Several species have been documented to undergo suspended animation during early development when in the complete absence of oxygen and/or freezing cold. Mimicking torpor and hibernation, animals under suspended animation display near halted metabolic rates with concomitant drop in heart rate, brain activity, and overall cellular activity. Upon re-exposure to oxygen and/or rewarming, physiological processes start up again and the organism lives out a normal lifespan. The applications for suspended animation in humans are far spanning from deep space exploration with living astronauts to saving the lives of victims of severe trauma. Furthermore, the means by which suspended animation can be induced with high survival rates during re-emergence is relatively simple and can be induced via several methods. In 2005, researchers in Seattle discovered the use of hydrogen sulfide gas in inducing suspended animation and were able to successfully place mice in near metabolic arrest for 6 hours with normal exit. This was the first time a mammal was successfully suspended and suggests it could be extended to humans.

• The incredibly brief Science paper

A very recent and awesome paper on suspended animation