Cryonics is the process in which those who have died are preserved by keeping them at a very low temperature until a means is developed to reverse the cryonics process and a cure for their illness or death is found.
So far cryonics is only a theory. No adult human has ever been revived as a result of a cryonics procedure. Although human embryos can be successfully cryopreserved and revived.
The cryonics procedure is begun when the heart stops beating – cardiac arrest (legal death). Blood circulation and oxygenation are restored in the cryogenics patient, to prevent deterioration, and the cryonics preservation procedures begin.
It costs between $80 and $130,000 depending on whether you request whole body to neuropreservation. Many people pay for it with life insurance.
The majority of cryonics organisation are situated in the US. Michigan-based Alcor, for example, has 650 future patients signed-up and 59 cryopatients. Future patients have wristbands and a card giving detailed instructions on what should happen on their death ie that no post mortem is carried out.
Cryonics Europe, based in the UK, has a team of volunteers trained to carry out the first stages of the preservation process. This includes putting the body in a portable bath filled with dry ice and attaching it to a machine designed to maintain circulation – this stops the further deterioration of cells. The blood is then drained off and replaced with a glycerol which works a bit like anti-freeze. Then the corpse is wrapped in polythene, submerged in alcohol, placed with ice and insulated in a fibre-glass box before being airlifted to Alcor in Michigan. Once in Michigan is it immersed in liquid nitrogen which sends its temperature plunging to -196C.
More detailed information on the procedure can be obtained from the Alcor web site and the contacts in this section.