What is an important step when treating a casualty with extremity frostbite?

Covering the extremities with wool blankets is a crucial step in treating a casualty with extremity frostbite because it helps to gently rewarm the affected areas while providing insulation and preventing further heat loss. Wool retains heat well, even when wet, and offers a layer of protection against the cold environment, which reduces the risk of further tissue damage. This method allows for gradual rewarming rather than exposing the frostbitten extremities to direct heat sources or extreme temperatures that could cause additional harm.

Using direct heat, such as heating pads or direct skin contact with hot surfaces, can lead to burns or further tissue injury. Placing the extremities in hot water can also expose them to the risk of thermal injury, as the water temperature might be too high and could cause damage to already compromised tissues. Keeping the extremities exposed to the air is not advisable, as it can lead to further cooling and exacerbate the condition of frostbite. Therefore, using wool blankets is the safest and most effective approach for managing frostbite in an extremity.