Source:http://linkedlifedata.com/resource/umls/id/C0993628
UMD: Compresses or packs designed to apply moist heat therapy to a specific body surface. These devices typically consist of soft pads made of several layers of cotton, gauze, or linen (i.e., compresses), or compact plastic or fabric bags (i.e., packs) that may contain heat-retaining substances such as gels, or rice, corn, or micro beads that are capable of conforming to the contour of the body. Hot compresses can be warmed by immersion in hot water or by using a microwave oven; some compresses become hot due to a chemical reaction. They draw moisture from the humidity in the air or by immersion in hot water (e.g., moist heat therapy pack conditioner). Hot compresses and/or packs are used mainly to improve blood circulation and reduce pain, muscle spasms, and joint stiffness.