TURNING science fiction into science fact, American doctors are preparing to chill volunteers into a state of suspended animation that could keep them asleep for months.

Medical teams in Los Angeles, Boston and Pittsburgh are racing to become the first to test out new theories of “induced hibernation” which could save lives and also help to send man towards the stars.

Hasan Alam, a surgeon at Massachusetts general hospital and consultant to the US army, is poised to start the first human trials before the end of the year.

Last week he said that he wanted to equip ambulances with a clear saline solution called plasma expander that would be injected into seriously injured victims at the scene of a car accident.

The plasma would rapidly send body temperature from 37C to 10C, slowing the metabolism, delaying the onset of shock and limiting damage from wounds.

Alam has experimented on eight-stone Yorkshire pigs, stopping the heart and electrical activity in the brain for up to two hours before slowly replacing the plasma with warm blood and reviving the animals with no apparent long-term effects.

The plasma could also be tested on soldiers: many survive an initial injury only to die waiting for treatment.

Alam, a trauma specialist, is primarily thinking about the time-critical dash to hospital. But researchers at the University of California, Los Angeles (UCLA) and the Safar Center for Resuscitation Research at the University of Pittsburgh are more ambitious. “You start with 20 minutes and then find the limits – days, weeks, months, we do not yet know,” said a UCLA medical school researcher.

Although it is 20 years since Nasa abandoned work on induced hibernation as a way of helping astronauts to survive long space missions, research began again at the European Space Agency in 2004. Funding has flowed in the United States since October, when Mitsutaka Uchikoshi, 35, strayed from a Japanese office barbecue, fell down a snowy mountain and broke his hip.

He lapsed into a frozen coma, which lasted 24 days until his apparently lifeless body was found and revived in a Kobe hospital. He is now known in Japanese newspapers as the “Bear Man”.

“We don’t know how he survived so long, but his body was preserved in ice for nearly a month and now he is back to normal,” a Kobe doctor said. “If we can understand why, we can save many lives in the future.”

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