Cryopreservation

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Cryopreservation, the main procedure in cryonics.

Pre Arrest[править]

Standby[править]

Alcor has teams of volunteers all over the United States trained to stand by a patient, apply anticoagulants and CPR, and transport the patient until proper cardiopulmonary support can be secured.

Suspended Animation (The company) has an equipped ambulance that is used to stabilize and transport Alcor and CI patients (Of the latter, only those who have explicitly made arrangements with SA). In some cases, a charter jet has to be used to transport the patients.

Pretreatment[править]

The rationale of pharmacological pre-treatment is that cryonics Patients should not have to wait until legal death before application of anti-coagulant and anti-oxidant medications, when much higher levels in blood and tissue can be achieved if these are administered prior to legal death.

The three objectives of pre-treatment are

  • Prevent Clotting: Reducing clotting is of great benefit, as it the reason why Heparin is universally applied after legal death. Clotting prevents proper cryoprotective perfusion. In cases where the patient is undergoing surgery, however, clotting is desired, and as such anti-coagulants cannot be administered.
  • Prevent Edema: Edematous tissue has the same adverse effects as clotting: Edema constricts blood vessels, sealing large volumes of tissue away from cryoprotectant solutions.
  • Prevent Ischmemia: When tissue is deprived of blood flow (And thus Oxygen), especially brain tissue, large amounts of damage occur. Excessive cerebral ischemia can make the best cryonics effort useless, due to the loss of fundamental properties of brain tissue and by causing edema.

Drugs:

  • Alpha-tocopherol Form of Vitamin E:
    • Administration & Dose: IV, 20mg/kg, 30 minutes prior to ischemia.
    • Has been shown to significantly reduce lipid peroxidation and neurological damage [1]
    • has the additional advantage of reducing blood clotting
    • does not have the risk of gastric bleeding associated with aspirin
  • Fish Oil (especially salmon oil):
    • Same benefits as the above.
    • reducing the risk of cardiac arrest [2].
  • Lipoic Acid:
    • is beneficial in reducing ischemic-reperfusion injury by direct action as well as by glutathione protection and xanthine oxidase inhibition[3].
  • CoEnzyme Q10:
    • has been shown to protect rat endothelial cells from ischemia & reperfusion injury[4].
    • Human cardiac arrest patients admitted to a hospital within 6 hours of cardiac arrest given a 250 mg loading dose of CoQ10 showed 68% survival compared to 30% of controls.
    • Of the survivors, 36% of the CoQ10 group had good neurological outcome, in contrast to 20% of controls [5].
  • N-acetylcysteine:
    • Dose: 15 grams.
    • When infused in human myocardial infarction patients over a 24-hour period it significantly reduced ischemic damage[6].
  • Curcumin:
    • This phytochemical is powerful antioxidant which is several times more potent than Vitamin E[7]

Vitamin C should not be used for ischemia/reperfusion pretreatment. While normally it is an anti-oxidant, it becomes a powerful pro-oxidant in the presence of the metal ions which are released, in large quantities, by ischemic brain tissue.

  • Summary: (For patients weighing 100 kilograms)
    • Alpha Lipoic Acid: 600mg per day of the R form, or 1000mg of the Racemic form.
    • CoEnzyme Q10: 500mg per day.
    • Tocopherol: 2,000 IU per day (Equal amounts of alpha and gamma).

Post Arrest[править]

Stabilization[править]

Cooling is performed by placing water ice around the head and on the areas of the body where high-throughput veins and arteries exist close to the surface (The axilla, neck and groin). The damage equivalent of five minutes of room-temperature ischemia, at the temperature of ice, takes 180 minutes to occur.

Transport[править]

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Perfusion[править]

Vitrification[править]

In essence, vitrification is the depression of the freezing point of water until it is below the Glass Transition Point (Tg), at which water and the tissues around it become a glass, and ice formation cannot occur.

Cryoprotectants[править]

A cryoprotectant is any substance that protects biological tissue from freezing damage (Ice formation).

Cryoprotectants such as polyols, sugars and glycols are naturally produced by some forms of life inside the arctic and antarctic circles to protect themselves from the winter. Some arctic salamanders produce glycerol in their livers as a cryoprotectant.

Cryoprotectants can be divided into two categories: Conventional and solutions. Conventional cryoprotectants are glycols, such as Ethylene glycol, glycerol; and dimethyl sulfoxide. Solutions are mixtures of conventional cryoprotectants and/or other chemicals, and are designed to reduce toxicity to biological tissue and increase effectiveness.

M-22[править]

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CI-VM-1[править]

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Ethylene Glycol[править]

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Glycerol[править]

Source: Mike Darwin. History of DMSO and Glycerol in Cryonics. Cryonics, Third Quarter 2007.

The use of glycerol as a cryoprotectant for cryonics patients was first proposed in the founding book of cryonics, The Prospect of Immortality, given that it was the most used cryoprotectant agent at the time (1962-1964) and good preservation of sperm and tissue using glycerol had been demonstrated.

DMSO[править]

DMSO was introduced in the mid-to-late sixties due both to its skin-penetrating, anti-inflammatory properties and the charisma of Stanley W. Jacob, the "father of Dimethyl Sulfoxide".

Propylene Glycol[править]

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Tissue Comparison[править]

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Burr Hole[править]

Cooling[править]

In cryonics, several forms of cooling have been used:

  1. Dry Ice: The patient is surrounded by dry ice until reaching a temperature of -78.5 ºC.
  2. Spraying of Liquid Nitrogen Vapor: The method used by CI consists of placing the patient inside a cooling box on a supine position. Liquid Nitrogen vapor is sprayed from an overhead tube and is distributed by a fan.
  3. Isopropyl Alcohol: The patient is immersed in a bath of alcohol.
  4. Immersion: The patient, either a Whole Body or a Neuro is slowly immersed in Liquid Nitrogen, with the vapor providing interim cooling. In the case of neuropatients, the Neurocan was placed in a cryogenic dewar which was immersed in the Liquid Nitrogen.

(Note that in cooling the patient is already placed in a sleeping bag or another form in insulation.)

Long Term Storage[править]

Whole body patients are stored head-down so that in the event of a leak, the head remains immersed, preventing thawing for some time while the problem is solved. More over, boil off of the Liquid Nitrogen happens continuously and the liquid is only replaced occasionally; because of this, parts of the patient could become exposed to Nitrogen vapor until it the dewar is replenished. This temperature changes can cause additional damage and fracturing from thermal stress.

In the early years, patients were stored in horizontal dewars and later vertically but head-up. Head-down storage was proposed, but relatives of patients at the time said it would be disrespectful to store them on their heads.

Proposals of large, multi-thousand-patient storage facilities have been found in Cryonics literature since its inception. An early example is the article written by Pauline Mandell in Coronet about her son's cryopreservation (See Patients), in which she mentioned proposals for the construction of large 'cryo-sanctorums' several stories tall to house thousands of patients. While a large facility would have the definite advantage of having boil-off times measured in months or years; a simple leak may prove impossible to repair without transferring the patients to other locations with the same storage capabilities. This would involve significant risk in thawing and a potentially exorbitant cost.

HSSV Cryostat[править]

Upright MVE[править]

Small MVE[править]

Neurovault[править]

The neurovault or 'cephalarium' used by Alcor was the world's first radiation, fire, earthquake and blast-resistant store of cryopatients.

Currently the Cephalarium lies abandoned behind the Scottsdale facility, while Alcor's Patient Care Bay is only secured on the wall that can be viewed by visitors.

Galiso dewar[править]

Bigfoot[править]

King Kong[править]

The King Kong Kapsule, built by TT engineer John Day, was the largest hard-vacuum dewar ever built, and was designed to hold eleven (Whole body) patients, even though its inside diameter was only 64 inches[8]. The King Kong was put into service in 1990, when TT had enough patients to justify it. The dewar held eight patients, and never performed to specifications [9] [10]. The Kong's performance was described as "subpar" [11] by Trans Time's engineer John Day, as its Liquid Nitrogen boiloff rate was 73 liters per day (1.5% of its capacity boiled off every day). When the Kapsule had 8 patients, this rate works out to a little over 9 liters of Liquid Nitrogen, every day, for every patient: A cost 300% greater than Alcor's[12]. Because of allthese failures, they never payed more than half the contract price.

The King Kong was finally replaced with a modification of Alcor's design for a four patient dewar, which they called the Son of Kong and had 30% of the boiloff rate of the King Kong.

Forever Flask[править]

The 'Forever Flask' was the first dewar built by Minnesota Valley Engineering for the storage of cryopatients. It was made by welding together two standard A-8000 MVE dewars (Used for storage of biological specimens: Tissue cultures, bull semen of the Minnesota Valley Breeders Association), which had 25 neck tube opening; wide enough, but not tall enough, for the storage of two human patients, but not tall enough.

It was built in 1969, using $5,000 of the $11,000 dollars given to CSNY by Nick DeBlasio; and held his late wife and a yet-to-be-identified Beverly Hills woman that Robert Nelson had frozen.

Intermediate Temperature Storage[править]

Emergency Procedures[править]

At Alcor, in case of an emergency, all whole body patients are to be converted to neuropatients. This would allow the current patient base of Alcor to be stored in two Bigfoot dewars.

In 1983, TT converted three whole-body patients to neuros and transported them to Alcor due to lack of funding for continued cryopreservation. (See Postmortem Examination, Ray Mills and Katherine Mills).

References[править]

  1. STROKE 14(6):977-982 (1983)
  2. MOLECULAR AND CELLULAR BIOCHEMISTRY 116(1-2):19-25 (1992)
  3. FREE RADICAL BIOLOGY & MEDICINE; Packer, L.; 19(2):227-250 (1995)
  4. SURGERY; Yokoyama,H; 120(2):189-196 (1996)
  5. CIRCULATION; Damian,MS; 110(19):3011-3016 (2004)
  6. CIRCULATION 92(10):2855-2862 (1995)
  7. THE JOURNAL OF NEUROSCIENCE 21(21):8370-8377 (2001)
  8. http://www.cs.cmu.edu/afs/cs/user/tsf/Public-Mail/cryonics/archive/333
  9. http://www.cryonet.org/cgi-bin/dsp.cgi?msg=5404
  10. http://www.cryonet.org/cgi-bin/dsp.cgi?msg=320
  11. John Day, TT's chief of engineering in the October, 1981 issue of Cryonics magazine. "Economics of surrounding a vacuum insulated dewar with additional foam insulation" CRYONICS pp. 13-18
  12. http://www.cs.cmu.edu/afs/cs/user/tsf/Public-Mail/cryonics/archive/333