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Cold pack

The use of cold as a therapeutic treatment is as old as the practice of medicine. For many years, physicians, trainers and coaches of athletic teams have utilized the application of cold to treat sprains or fractures. Cold therapy helps reduce or prevent the swelling and pain that accompany musculoskeletal injuries. It can also be used to treat or prevent heat exhaustion, or for general cooling of the body. Cold's therapeutic effects are the result of a reduction in the local metabolic activity of underlying tissues, the slowing of nerve conduction and, by its direct effect on muscle spindle activity, the reduction of muscle spasm. Cold is also used to slow bleeding, for example, nosebleeds and the like, to reduce the pain and swelling of wounds, to slow the absorption of snake bite poisons by reducing the blood flow in the bite area and for other medical applications. Injuries to the body, such as a broken arm, a broken leg or an ankle strain, are common to people all over the world. It is well known that to adequately treat such an injury, the injured part of the body should be elevated, immobilized and cooled with a cooling device. When an injury occurs, the blood vessels in the area dilate and release fluid into the injured tissue, thus causing swelling and pain. Reducing the circulation in the area by application of cold reduces the accumulation of fluid and thereby minimizes the swelling in the area. The early application of a cold pack device to the injured area constricts the blood vessels and reduces the loss of fluid into the injured area. Thus, while cold therapy reduces the circulation to the site of injury, it is only for a relatively short period of time. It prevents the swelling which would prolong the period of disability and thus retard healing. Cold also relieves the pain of an injury by desensitizing nerve endings. When cold is first applied to an affected area, there is a gradual onset of numbness produced by a slowing of the sensory conduction. Then there is an inhibition of all sensory perception of the area, including pain. The application of cold to an injured surface also helps to stop bleeding. Cold packs may be of several general types. Ice bags, gel packs, chemical cold packs, immersion and ice massage are the most common methods for delivering cold therapy. There are those cold packs that contain an insulating material which, upon cooling in a refrigerator or freezer, gradually warm back to ambient temperature. There are those cold packs that operate via a change of phase of the components of the cold pack. There are also those cold packs that employ chemical components that dissolve endothermically in a solvent.

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