For this reason, patients who present for cryonics are protected from ice damage by using a cryoprotective agent to reduce, or even eliminate, ice formation. Conventional extracorporeal bypass technologies are used to circulate the solution throughout the body. When enough water is replaced with the cryoprotective agent the patient is maintained at cryogenic temperatures for long-term care. Historically the cryoprotective agents that were used in cryonics.
CI−VM−1 is a more powerful and much less expensive cryoprotectant mixture than M22, but it is more toxic. CI−VM−1 was optimized on hippocampal slices by cryobiologist Dr. Yuri Pichugin. [ For information on cryoprotectant toxicity, see TOXICITIES OF CRYOPROTECTANT AGENTS. For a more detailed analysis/explanation of M22 see Vitrification agents in cryonics: M22. For a description of the use of M22 by Alcor see New Cryopreservation Technology.