Why should the affected extremity be kept above the heart in the case of snakebite?

Keeping the affected extremity above the heart in the case of a snakebite is primarily aimed at preventing the spread of venom throughout the body. When a body part is elevated, it helps to slow down the movement of venous blood and lymphatic fluid, which can contribute to the distribution of the venom. This elevation reduces the hydrostatic pressure in the veins and can limit the rate at which the venom spreads through the circulatory system. By minimizing motion and keeping the extremity elevated, you help to isolate the venom to a more localized area, which is critical in managing the effects of the bite until medical assistance can be obtained.

While reducing swelling and pain can be important in managing injuries, the main focus in the context of snakebites is on controlling the spread of venom, making this the most relevant reason for keeping the affected limb elevated.