a. The reasons for applying cold are to prevent edema, relieve pain, decrease circulation, decrease metabolism, and to slow or stop bleeding.

The effects of cold are to decrease blood flow, oxygen, tissue temperature, local metabolism, lymph flow, to enhance blood clotting, and to slow nerve impulses.

b. As when applying heat, apply cold only according to directions of a physician or supervisor. Nerves in the skin are easily numbed, and the patient may not feel any pain. Therefore, it is up to you to discontinue any cold application if the patient complains of numbness, if the skin looks white or spotty, or if the patient develops a rapid pulse, bluish lips, bluish nail beds, or chills.

Keep the temperatures between 40 to 80 degrees Fahrenheit, and check with the physician if you are unsure. Then check with the patient to be sure the application is not causing pain.

c. Methods of applying cold include chemical cold packs, ice bag for head, collar, cold soaks, cold compresses, and a cold or tepid alcohol sponge bath. Always place a hand towel over the treatment site before applying any wrapped cold pack.

d. Cases or conditions when cold is not used are 24 hours after a burn or sprain injury, elderly patients with decreased metabolic rate, arthritic patients, and very young children. The possible complications resulting from the use of cold are chills, pain, maceration, ischemia, blister, and hypothermia.