Bodies Response to Injury There are 3 phases of healing. Inflammation Inflammation Repair/Regeneration Repair/Regeneration Remodeling Remodeling

Bodies Response to Injury Inflammation is the body’s reaction to invasion by infectious agent.(1-6 days) 1. Blood supply to area increases, the blood vessels dilate. 2. Capillary permeability increases. Allows specialized cells to reach injury site.

Bodies Response to Injury 3. Leukocytes (? blood cells) migrate into surrounding tissue. Neutrophils surround bacteria and kill it.

Bodies Response to Injury A variety of interconnected cellular and body fluid mechanisms are activated when tissue damage and infection occurs.

Bodies Response to Injury Chronic inflammation can occur when there is ineffective elimination of damaged tissue.

Bodies Response to Injury Repair/Regeneration(day 4- 10days) - 1. Once damaged tissue is degraded by the leukocytes, generation of new tissue can begin. 2. If damage is severe, wound cannot repair to normal status. Scar tissue will develop.

Bodies Response to Injury Remodeling-(day 7-several weeks) 1. Formation of new blood vessels covering the wound 2. Migration of fibroblasts to fill and bridge wound. 3. Maturation and reorganization of the fibrous tissue into a scar

Bodies Response to Injury Remodeling can last up to a year -collagen fibers thicken and strengthen -the scar tissue that develops is 80% strength of normal tissue -there is replacement of lost cells, as well as regeneration of old.