At present there are only a few active cryonics providers, organizations that can cryopreserve an individual at death in order to maintain the structure of the mind indefinitely, waiting on a future in which the technology exists to allow restoration to active life. Cryonics offers the only shot at a longer life in the future for those who will age to death prior to the advent of working rejuvenation therapies. The odds are unknown, but certainly infinitely better than those associated with any of the other available options at the end of life. Most cryonics providers and their support organizations are in the US, and the oldest have been in business since the 1970s. Another more recently established provider operates in Russia. That leaves much of the world without any easy access to cryonics as a service, though volunteer organizations in a number of countries are working towards the establishment of providers at varying speeds and with varying degrees of success. One of the more recent of these is the European CryoSuisse, whose principals will be hosting the 1st International Cryonics Conference this coming November:
Cryonics is an experimental medical procedure to save human lives. Very low temperatures are used to effectively halt the time - for decades or centuries, until the day when the medicine of the future is capable of reviving the patient and cure his illnesses. Cryonics is based on the most recent insights of cryobiology and medicine. Already today, human embryos are routinely cryopreserved at low temperatures and re-animated later. Even for individual organs, cryonic techniques are already in use. A good cryopreservation of patients which today's medicine can no longer help is already possible. CryoSuisse, the Swiss Society for Cryonics, advocates the promotion, further advancement and practical application of cryonics - in order to give as many people as possible the chance to continue their lives in the future.
How does it work?
Nowadays, many serious illnesses can be cured which had been fatal as recently as one century ago (e.g., tuberculosis, smallpox or kidney failure). One can expect that medicine will proceed just as fast during the centuries to come. The cryonicist waits until the illness he suffered from can be cured. In other words, cryonics is an ambulance service through time.
Are the body tissues not destroyed by the cold?
At temperatures below 0 °C, water freezes into ice crystals. With their sharp edges, ice crystals destroy individual cells and tear tissues apart. Therefore, cryonics does not freeze the body, but vitrifies it. To this end, the bodily fluids of the human are replaced by cryoprotectants which protect the cells and prevent the formation of ice crystals. In this way, the body is transformed into a glass-like state where cells and tissues retain their original structures.
But can this glass also be converted into a fluid again?
Yes it can, this is scientifically proven. For example, researchers have thawed a kidney which had been vitrified at -130 °C and successfully transplanted it into a rabbit. The transplanted kidney recovered quickly to its normal function.
Then why is it that there are no reports about humans who were revived from this state?
Although some individual organs can already be cryopreserved, it has not been possible so far to cryopreserve a living being and revive it thereafter. There are several research programs to improve the technique though. Nevertheless, cryonics already makes sense: The fact that patients cannot be revived using today's techniques does not mean that it's not possible in future.