What does Calor refer to in the context of acute inflammation?

Calor refers to the sensation of heat that is observed in the area of inflammation during an acute inflammatory response. This term originates from Latin, where "calor" means heat. The increase in temperature is due to the heightened blood flow and metabolic activity in the affected tissues, caused by the body's response to injury or infection.

In the context of acute inflammation, the four classic signs are redness, heat, swelling, and pain. Heat occurs as the blood vessels dilate (vasodilation), allowing more blood to flow to the injured area. This increased blood flow not only delivers immune cells to help fight infection and clear debris but also raises the local temperature, which can aid in the healing process and inhibit the growth of pathogens. The presence of calor is a key indicator of inflammation and serves as an essential part of the body's defense mechanism.