Acute Inflammation Flashcards
What 6 things cause Acute Inflammation?
- Micro-organisms
- Mechanial trauma to tissue
- Chemical changes
- Extreme physical conditions
- Dead tissue
- Hypersensitivity
What are the cardinal signs of inflammation?
- Rubor (redness)
- Calor (heat)
- Loss of function
- Tumor (swelling)
- Dolor (pain)
Aetiology of acute inflammation?
- pathogenic organisms
- trauma
- chemical (acid/alkali or misplaced bile/urine)
- physical conditions (sunburn, frostbite, radiation)
- Dead Tissue irritates adjacent tissue
- Hypersensitivity
Whats microcirculation?
- Capillary beds fed by arterioles & drained by venules.
- Extracellular space & fluids/molecules in it.
- lymphatic channels & drainage
Pathogenesis of acute inflammation:
- changes in vessel radius (flow)
- Changes in vessel wall permeability (exudation)
- neutrophil movement from vessel to extracellular space
Whats the triple response?
Flush. Flare, Wheal.
What are the 3 types of vessel radius change?
1) Transient arteriolar constriction
2) local arteriolar dilation
3) Smooth muscle relaxation
Why increase local blood flow?
To cause rubor & calor
What causes vessel permeability change during acute inflammation?
Local chemical mediators (chemokines) produce a leak in the endothelium
What are the effects of increased vessel permeability?
Think exudation
net movement of plasma fluid & protein from capillaries to extracellular space. (exudation) Includes immunoglobulin & fibrinogen
What is the effect of exudation?
Oedema
Accumulation of fluid in extravascular space.
exaplins swelling, pain & reduced function.
How does increased permeability effect flow?
It slows it down because of increased viscosity. Stasis.
In short what are the 3 stages of neutrophil movement from the vessel to the extravascular space
Margination
Pavementing
Emigration
What is margination?
Nuetrophils move to the endothelial aspect of lumen.
Normal in centre of vessel.
What is pavementing?
Neutrophils adhere to endothelia
