Frostbite and Hypothermia Symptoms and Stages
Benjamin C. Wedro, MD, FACEP, FAAEM
Medical Editor: Melissa Conrad Stöppler, MD
Frostbite and hypothermia are the consequences of cold exposure and both can have long lasting effects.
Not all organs in the body are created equal. While the body tries to maintain a constant temperature where heat production is balanced by heat loss, it is quite willing to sacrifice expendable parts like arms and legs to protect vital organs like the heart and brain. When exposed to a cold environment, the body tries to keep blood circulating away from the skin where it can be cooled by the outside weather. Shivering starts to generate heat and can compensate well if the cold exposure is short-lived. If, however, the body remains in the cold, bad things can happen very quickly.
What is paradoxical undressing?
Interestingly, there is a phenomenon called paradoxical undressing, in which the cold person actually undresses instead of trying to bundle up more. It is not uncommon for the hypothermic victim to just curl up in a snow bank and die. The heart also does strange things when it gets cold. A normal heart rhythm can become irritable and eventually degenerate into ventricular fibrillation, in which the bottom chambers of the heart jiggle like a bowl of jello. This lack of electrical impulse doesn't allow the heart to beat and pump blood to the body and is one of the causes of sudden cardiac death.
What are the symptoms and stages of frostbite?
The stages of frostbite are similar to those of burns.
- Frostnip or first degree frostbite is superficial and reversible but may cause significant pain when the extremity rewarms.
- Second degree frostbite is characterized by blisters that form a few hours to a day after injury and signify deeper tissue damage.
- Third degree frostbite describes skin that has been damaged though all its layers and tissue that turns black and hard as it dies.
Cold is a dangerous element, so don't let hypothermia catch you!