Classic signs of inflammation include heat, redness, swelling, pain, and loss of function, although they may or may not all be present. These symptoms result from physiologic changes that occur during the inflammatory process. Briefly, major components of the inflammation process include:
· Hemodynamic changes – blood vessels begin to dilate, which allows for increased blood flow, accounting for redness and heat.
· Increase capillary permeability – tiny blood vessels in the microcirculation start to allow fluid to leak out into the surrounding tissue. This contributes to swelling and edema around the site.
· Exudation – the oozing of fluid, pus, or serum, as well as white blood cells that rush to the site do what they can to neutralize the damage or take out the germs or foreign particles. This, too, contributes to the swelling and pain.
Taken together, even when the inflammation is contributory to healing, there is usually pain and some loss of function, at least temporarily.