A burn is an injury to tissue resulting from heat, chemicals, or electricity. Most people think heat is the only cause of burns, but some chemicals and electrical current can burn as well. Although the skin is usually the part of the body thats burned, the tissues under it also can be burned, and internal organs can be burned even when the skin is not.
For example, drinking a very hot liquid or caustic substance such as acid can burn the esophagus and stomach. Inhaling smoke and hot air from a fire in a burning building can burn the lungs. Tissues that are burned may die. When tissues are damaged by a burn, fluid leaks from blood vessels, causing swelling.
In an extensive burn, loss of a large amount of fluid from abnormally leaky blood vessels can cause shock. In shock, blood pressure decreases so much that too little blood flows to the brain and other vital organs. Electrical burns may be caused by a temperature of more than 9,000ﾰ F., generated by an electric current. when it passes from the electrical source to the body; this type of burn, sometimes called an electrical arc burn, usually completely destroys and chars the skin at the currents point of entry into the body.
Because the resistance (the bodys ability to stop or slow the currents flow) is high where the skin touches the currents source, much of the electrical energy is converted to heat there, burning the surface. Most electrical burns also severely damage the tissues under the skin. These burns vary in size and depth and may affect an area much larger than that indicated by the area of injured skin.
Large electrical shocks can paralyze breathing and disturb heart rhythm, causing dangerously irregular heartbeats. Chemical burns can be caused by various irritants and poisons, including strong acids and alkalis, phenols and cresols (organic solvents), mustard gas, and phosphorus. Chemical burns can cause tissue death that can slowly spread for hours after the burn.
This article was culled from the publications of Deen Communication Limited