Flashcards in Acute Inflammation Deck (20):
What are the signs of inflammation?
Rubor - redness
Calor - heat
Tumour - swelling
Dolor - pain
Loss of function
What are the causes of inflammation?
Physical - extreme conditions (heat, cold, radiation)
Necrosis (dead tissue irritates adjacent tissue)
What is the microcirculation?
Capillary beds (arterioles and venules)
Extracellular space including the fluid molecules within it
Lymphatic channels and drainage
What is oncotic pressure / colloid osmotic pressure?
Proteins exerted by proteins in the blood vessel plasma
What is hydrostatic pressure?
Pressure exerted by a fluid
What controls movement of fluid across membranes?
What are the three stages of inflammation pathogenesis?
Change in vessel radius
Change in the permeability of the vessel wall
Movement of neutrophils from the vessel to the extravascular space
What are the local changes in vessel radius in the Triple response?
Transient arteriolar constriction
Local arteriolar dilation
Relaxation of smooth muscle
What does the increased blood flow result in?
Heat - Calor
Redness - Rubor
Where does increased permeability occur?
What is exudation?
The process whereby plasma moves from the capillary to the extracellular space
What is exudate?
The fluid that is leaked - rich in plasma proteins (immunoglobulin and fibrinogen)
What are the results of exudation?
Oedema is formed - accumulation of fluid in the extravascular space
swelling - pain - reduced function
What effect does exudation have on the blood viscosity?
Increased viscosity - rate of blood flow slows down - stasis
Describe the structure of the blood flow in inflammation
RBC's aggregate in the centre of the lumen, neutrophils found near the endothelium
What are the phases of emigration of neutrophils?
Margination (Neutrophil moves to endothelial aspect of lumen)
Pavementing - Neutrophils adhere to endothelium
Emigration - Neutrophils squeeze between endothelial cells
What happens if there is a resolution of the acute inflammation?
Inciting agent is isolated and destroyed
Macrophages digest debris
Epithelial surfaces regenerate
Inflammatory exudate filters away
Vascular changes return to normal
What are the benefits to acute inflammation?
Rapid response to non-specific insult
Protection in inflamed area from cardinal signs
Neutrophils destroy organisms and denature antigen for macrophages
Movement of blood cells outside the capillary.