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Medicine In Traveller - Cryobiology

Cryobiology
the study of the physiology of low temperature.

Prior to the advent of modern medical science, it had been observed that survival from severe hypothermia was possible, if uncommon.

Many animals enter states of dormancy to conserve water and energy during particularly adverse climatic conditions e.g., dormice and bears, lungfish and some desert toads on Terra. However, there is a limit to how long dormancy can be maintained. Metabolism continues, albeit at a greatly slowed rate.

Long term tissue preservation requires metabolic arrest. To effect this, cell water must be locked in place to prevent cellular proteins from working. Water unfortunately expands on freezing (crystallisation), which causes cell rupture and death. It had been observed that rapid freezing limited the size of ice crystals formed. Immersion in liquid nitrogen (-196C) was used to preserve sperm, ova, embryos, seeds and pollen as early as Tech Level 6. By Tech Level 8, it had been shown that animals such as frogs and mice could be snap-frozen, thawed and revived. Survival rates were predictably low. The great breakthroughs which usher in the modern era of low berthing take place at Tech Level 9.

Hibernation

'Fast drug' is a combination of cell signalling factors and receptor blockers which are typically discovered in the course of early research into metabolism and aging. Its effect is to slow down metabolic rate a staggering sixty times. Unconsciousness ensues within two minutes of adminstration. Body temperature attains ambient levels within four to six hours. As a result, muscle rigidity is typical (below core temp 25C). It is difficult to distinguish between fast drug administration, severe hypothermia or recent death. TL 9+ blood testing will identify fast drug residues.

Fast drug induced dormancy is referred to as hibernation. It can be augmented by cooling to cause further slowing of the metabolism (chill berthing) or, with sufficient precautions, be used as a sole agent (fast berthing). Intravenous hydration is required, and should be given through an infusion pump so that therate is optimally controlled.

Minimum monitoring for fast berthing : ECG/EKG.
Minimum monitoring for chill berthing : ECG/EKG, serum levels of fast drug weekly, cooler system monitoring (tight control of temperature required).
(ECG/EKG - electrocardiogram)

All facilities must have readily accessible resuscitation equipment. Chill berths above TL 12 usually have built-in automeds, or provision for these to be installed. Chill berthing operating temperature is usually 4C (39.2F). Water is at its maximum density. Bacterial and fungal
growth is maximally inhibited.

Fast drug takes about two months or sixty days to be eliminated. Agents which can safely reverse the effect before this time are not developed until TL 12.

Freezing (Vitrification)

It is generally realised that the size of water crystals formed is the main determinant of successful revival from freezing. The development of compounds which depress the freezing point of water without being toxic to an organism enables the first successful revival from cryogenic freezing at about the same time as the development of hibernation. Cryogenic freezing technology becomes known as vitrification, as tissue water is changed to a supercooled liquid and then a solid with falling temperature.

Installing a patient into low berth in the early days was equivalent to connecting them to life support. Infusion lines, airways and monitoring devices needed to be surgically connected. The procedure was expensive (low temperature high flow pumps, etc.) and hazardous. Failure rates of 5-10% were common.

The development of the gravisonic modulator at TL 11 greatly simplifies the process. Based on inertial compensator technology, this device enables cooling and warming at the cellular level. No antifreeze agents are required and monitoring requirements are greatly decreased. Failure rates are greatly reduced due to the generation of biomaps during the freezing process.

The emergency low berth is designed for use by unskilled personnel. At the earlier tech levels, prompt immersion in cryogenic fluid is used. More advanced versions use gravisonic modulators and minimal 'quick and dirty' biomapping procedures. Revival is somewhat more difficult under these circumstances.

Use of hibernation or vitrification technology.

Metabolic slowing or arrest is widely used in modern interstellar society. Critically ill patients can be stabilised and then placed in chill or low berths to await definitive treatment. Low berths enable cheap interstellar travel. There are some associations of unusual individuals who use low or chill berths to 'time travel' into the future ('timer clubs'). Some societies place criminals and dissidents 'on ice', as do some
athletic and mercenary organisations to extend the useful lifespans of their personnel.

Tasks for Cryobiology

Hibernation

To install someone safely into a chill berth
Average, Medical, Edu
This includes establishing IV access.
Fast berthing at -1 DM.
Failure : catastrophe check (see below)
Spectacular Failure : VF during cooling. Resuscitation required as per Trauma rules. Requires cardiac massage.
Spectacular Success : +2 DM to revival task
 
To safely revive someone from hibernation
Difficult, Medical, Edu
Fast berthing at -1 DM
TL 12+ at +2 DM (fast drug antidote)
gravisonic modulator at +2 DM
Failure : roll catastrophe check - if fails, adverse reaction or fast drug overdose apparent (1D damage). Task needs to be repeated.
Spectacular Failure : VF on warming. Resuscitation required as per Trauma rules.

Vitrification

To install someone safely into a low berth
(difficulty), Medical, Edu
Difficult at TL 9-10
Average at TL 11+
Failure and success : as per chill berthing.
 
To revive someone safely from vitrification
Difficult, Medical, Edu
DM -2 if emergency low berth
DM +2 if gravisonic modulator
Failure : catastrophe check
Spectacular Failure : VF on warming, resuscitate
 
To Avoid Catastrophe
(Difficult, Medical/First Aid (attendant), End (patient)
Failure: impose 1D damage

Long-term Considerations

Hibernation

Fast berthing 60:1 slowing of metabolism.
Chill berthing 600:1 slowing of metabolism.

Hydration is required to permit long-term hibernation. The maximum safe period of time without fluid replacement is three days (so 180 days with fast berthing or 1800 days with chill berthing). Beyond this, 2D damage per day (60 or 600 days) until treatment or death ensues.

With hydration
Starvation : rapid weight loss (1kg/d for first ten days then 0.3kg/d thereafter). -1 from Str and Dex every two days until zero. Then -1 from End every week until death or feeding ensues. Multiply durations by 60 or 600 depending on the hibernation type.

With IV (or gastric) feeding
Roll catastrophe check every year (infection at IV site?)

Vitrification

1 point of damage is sustained for every 25 continuous years spent 'on ice'.

Healing and recovery is as per trauma notes.

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