Fundamentals of Nursing Q 365
Nurse AJ is applying a warm compress. What should the nurse explain to the patient is the primary reason why heat is used instead of cold?
A. Minimizes muscle spasms
B. Prevents hemorrhage
C. Increases circulation
D. Reduces discomfort
Correct Answer: C. Increases circulation
Heat increases the skin surface temperature, promoting vasodilation, which increases blood flow to the area. Cold has the opposite effect: it promotes vasoconstriction, which decreases blood flow to the area. In general, heat therapy is also recommended prior to exercise for those who have chronic injuries. Heat warms the muscles and helps increase flexibility. The only time one should ever consider using cold to treat a chronic injury is after finishing exercising when inflammation may reappear. Applying cold at this time helps reduce any residual swelling.
Option A: Both heat and cold relax muscles and thus minimize muscle spasms. It reduces joint stiffness and muscle spasm, which makes it useful when muscles are tight. There is no advantage to using heat over cold. When muscles work, chemical byproducts are made that need to be eliminated. When exercise is very intense, there may not be enough blood flow to eliminate all the chemicals. It is the buildup of chemicals (for example, lactic acid) that cause muscle ache. Because the blood supply helps eliminate these chemicals, use heat to help sore muscles after exercise.
Option B: Heat does not prevent hemorrhage; heat causes vasodilation, which promotes hemorrhage. Apply an ice compress to the injury as soon as possible. This will cool down the tissues, lower their metabolic rate and nerve conduction velocity, resulting in vasoconstriction of the surrounding blood vessels and reduced inflammation.
Option D: Both heat and cold can reduce discomfort. Cold reduces discomfort by numbing the area, slowing the transmission of pain impulses, and increasing the pain threshold. Heat reduces the discomfort by relaxing the muscles. When an injury or inflammation, such as tendonitis or bursitis occurs, tissues are damaged. Cold numbs the affected area, which can reduce pain and tenderness. Cold can also reduce swelling and inflammation.