Why can’t we fix frostbite? If the frostbite is bad enough, the blood supply to the tissue will be cut off and it will die, possibly causing gangrene.
Frostbite can form in any temperatures below -0.55 °C because that is low enough for water to freeze. However, in mild temperatures such as that, frostbite is rare because it would take far longer and the person would most likely be able to get themselves somewhere warmer. Frostbite can set in much more quickly if the temperature is lower and if there is significant windchill. A strong wind will cause increased convection of the heat out of the body. Frostbite happens at the extremities, such as the nose, ears, fingers, and toes, because when the body gets cold it slows blood flow to these areas down to reduce heat loss and to keep more blood at the core.
There are four stages of frostbite. The first stage is often called frostnip. The exposed parts of the body go numb, the skin reddens, and it the area might swell slightly. When the area is warmed back up, there may be pain and tingling. There is usually no permanent damage at this stage, although the top layer of skin may slough off over the next few weeks.
The second stage is called superficial frostbite. The color of the skin changes from red to a paler color. The skin may feel hard as it starts to freeze. Large blisters may form on the surface of the skin. The body part can be rewarmed at this point, although there may be some lasting numbness because damage has already been done. Rewarming will be extremely painful and painkillers are often required. The skin will probably regrow under the blisters.
In the third stage, the tissue below the skin freezes. Blood blisters form on the skin and the skin goes blue-grey. In the fourth stage, muscles, tendons, and even the bone beneath the skin freeze. The skin becomes hard and there is no pain when the body part is rewarmed. This is because the body part is most likely dead. The skin becomes black and mummified. It goes black because the hemoglobin and the iron in the blood oxidizes.
So, why can’t we fix frostbite? Frostbite up to stage two is reversible. Frostbite from stage three onwards is usually not reversible. When the body part freezes, ice crystals form inside the cells. These ice crystals rupture cell walls and small blood vessels. Once the blood supply to the body part is cut off, it is starved of oxygen and nutrients and the cells begin to die. The enzymes that are usually kept safely inside the cells a free and they start to degrade the tissue. A second problem comes when the body part is rewarmed. The ruptured blood vessels start to clot, and the blood supply can still be cut off. This can cause severe damage when someone is stuck in a cold place and their body part freezes, thaws, and then freezes again. This can do more damage than just having the body part freeze. Doctors advise that if the body part can’t be kept warm, it shouldn’t be thawed until the person can get to the hospital.
When a person with severe frostbite is brought to a hospital, the doctors won’t know how much tissue has been lost and the first step is to warm up the affected areas. Once this has been done, they have to wait to see how much of the tissue is undamaged and they have to wait to see if gangrene has set in. There is a saying: Frozen in January, amputate in July.
Gangrene is a potentially lethal side effect of frostbite. If the blood supply to any part of the body is cut off for long enough that part will die, and the tissue will start to break down and decompose. Sometimes the dead body part might just drop off. This is called autoamputation. However, sometimes the dead body part will become infected with bacteria and the bacteria may start to spread to healthy tissue. In situations like this, the doctor will try to remove as much of the infected tissue as possible to save the rest of the body. This may involve amputation of the body part.
So, why can’t we fix frostbite? Because the damage to the tissue is not usually reversible. However, the sooner the body part can be rewarmed, the greater the chance that the damage will be minimalized. Hospitals will warm the body part up in a warm bath heated to body temperature. They will add iodine to kill any bacteria that may be present. They may also use blood vessel dilating drugs to try to reduce the damage. Technology is improving, but once the blood supply to a body part has been cut off for long enough, that body part will die and there is not much any hospital can do about it. And this is what I learned today.
Sources
https://www.nhs.uk/conditions/frostbite/
https://www.mayoclinic.org/diseases-conditions/frostbite/symptoms-causes/syc-20372656
https://en.wikipedia.org/wiki/Frostbite
https://www.healthline.com/health/frostbite-stages
https://www.thenakedscientists.com/articles/questions/why-frostbite-black
https://my.clevelandclinic.org/health/diseases/21070-gangrene
https://www.hopkinsmedicine.org/health/conditions-and-diseases/gangrene