Cryonics

Cryonics is the practice of cryopreserving people or animals (usually in liquid nitrogen) with the hope that future technology may be able to restore them back to life. Cryonics is controversial and it is not known whether or not preserved human bodies can eventually be revived.

History
Attempts to preserve human bodies in liquid nitrogen began in the 1960s. Many of the early cryonics organizations failed. The Cryonics Society of California preserved nine bodies in an underground vault at a cemetery, all of which were thawed due to a vacuum pump failure. Another early cryonics organization, the Cryonics Society of New York, depended on friends and family of cryopatients to make regular payments. Most people quickly stopped making payments, and most of the cryonics patients of the 1960s and 1970s thawed out. One survivor is James Bedford who is currently stored at the Alcor Life Extension Foundation.

Alcor was founded in 1972 and the Cryonics Institute was founded in 1976. Both organizations have investments to ensure long-term survival. KrioRus was founded in 2005 and Tomorrow Biostasis was founded in 2019.

Alcor
At Alcor, cryopreservation procedures consist of four stages: (1) deployment and standby, (2) stabilization, (3) cryprotectant perfusion, and (4) cryogenic cooldown. Ideally, the deployment and standby stage would begin with Alcor being notified of a pending death before a patient has legally died so that a standby team can be sent to monitor the patient as soon as possible, and would be able to begin stabilization as soon as possible after legal death. During stabilization, the patient is placed in ice water to slow chemical reactions. Medications are administered and chest compressions are performed by machines to keep blood circulating and pump air in and out of the lungs. Continuing circulation provides the brain with oxygen and distributes medications through the body.

The cryoprotectant stage is where chemicals are added to prevent ice crystals from forming. The sternum (breast bone) is cut to access the aorta and right atrium in whole body patients to distribute the cryoprotectant through the body. In neuro patients, a surgeon uses the cartoid arteries to send cryoprotectant through the brain. The last stage is the cryogenic cooldown, where whole body patients are placed in a cooling box, and neuro patients in a small dewar. Software controls the cooling process. Liquid nitrogen is inserted and then vaporized to remove heat from the patient, and a fan circulates the vapor. After a period of 4-5 days the temperature reaches -190°C. Whole body patients are transferred to a dewar in a sleeping bag where the body reaches -196°C (the temperature of liquid nitrogen). The dewar of neuro patients is gradually filled with liquid nitrogen.

Cryonics Institute
Unlike Alcor, the Cryonics Institute (CI) does not include standby services by default, but standby services can be purchased by Suspended Animation for patients of CI. Standby would be the the first stage for CI patients who arranged standby services. Otherwise, the initial cool-down and transport would be first. The patient should be cooled in ice water as soon as possible after legal death. An anticoagulant should be injected to prevent blood clotting and chest compressions are performed for at least five minutes to distribute the anticoagulant through the body. A patient who legally dies outside Michigan would be transferred to a funeral home, then a funeral director would send the body to either CI or the Detroit Metro Airport (where CI will pick up the body). Patients who legally die in Michigan can be sent straight to CI.

In the next stage, blood is replaced with cryoprotectants through the carotid arteries by small incisions along the clavicle. A thin tube to the brain and one to the heart are inserted in both arteries. Blood and water in the body are drained through the jugular veins. Once this is completed, the incisions are stitched and the patient is placed in an insulation pouch then on a stretcher to move the patient to the computer controlled cooling unit. In the last stage, the patient is cooled by the computer controlled cooling unit over a period of five and a half days. Then the patient is removed from the unit and transferred to a cryostat for long term storage, while the insulation pouch is saturated with nitrogen. Ropes and an electric lift are used to place the patient inside the cryostat.