The inflammatory response is chemically mediated. Although inflammation on the surface, i.e. edema, hot, painful, red, it actually is an important part of healing.
IV. Inflammation
A. Chemically mediated
B. Damage tissue – release chemicals or presence of pathogens alters interstitial fluid
C. Mast cells —- release histamine, prostaglandins, heparin
D. Histamine
1. Vasodilation — hyperemia (Redness and Heat)
2. Increase capillary permeability — fluid loss (Edema)
3. Edema puts pressure on nerve endings (Pain)
*The 4 cardinal signs of inflammation are redness, heat, edema, and pain.
E. Prostaglandins (PGs)
1. Group of arachidonic acid metabolites (phospholipids)
2. Vasodilation and Capillary Permeability
3. Sensitize pain receptors
4. Platelet aggregation – fibrin deposited — walls off injured site
5. Aspirin and other NSAIDs block the production of PGs
a. decrease inflammation
b. suppress platelet aggregation (blood thinner)
F. Heparin
1. Prevents clot at the actual site; clot occurs around site
G. Purpose
1. hyperemia
a. brings phagocytes, nutrients, and clotting proteins
b. dilute toxins
c. increase temp. — increase reactions
2. Neutrophils
a. chemotaxis and diapedesis
b. phagocytosis
c. respiratory burst – H2O2 and free radicals ( O2- )
3. Wall off area
4. Aids in repair
