Acute Inflammation Flashcards
what is inflammation
vascular phase
- changes in blood flow
- accumulation of exudate
cellular phase
-delivery of neutrophils
what causes inflammation
trauma/ foreign body
microorganisms
hypersensitivity
other illnesses
what are the clinical signs of acute inflammation
rubor calor tumour dolor loss of function
vascular changes to blood flow
vasoconstriction (seconds)
vasodilation ( minutes)- heat and redness
increased permeability - fluid and cells can escape
what is starlings law
movement of fluid controlled by the balance of hydrostatic pressure and oncotic pressure
hydrostatic pressure- pressure exerted on a vessel wall by fluid- pushes fluid away
oncotic pressure- the pressure exerted by proteins- draws fluid towards
what is stasis
reduced flow through vessel
what is exudate
increased vascular permeability
protein rich fluid (delivers proteins to area of injury)
occurs in inflammation
delivers proteins
what is transudate
vascular permeability unchanged
fluid movement due to:
-increased capillary hydrostatic pressure
-reduced capillary oncotic pressure
occurs in
-heart failure
-hepatic failure
renal failure
how do neutrophils escape vessels
1) margination- movement from middle of blood vessel to periphery of blood vessel
2) rolling- stasis reduced flow of blood allow neutrophil to marginate
3) adhesion - they get tethered to one another
4) emigration ( diapedesis) - movement of neutrophil cell into interstitium through to the middle or between
what are selectins
expressed on activated endothelial cells
cells activated by chemical mediators
responsible for rolling
what are integrins
found on neutrophil surface
change from low affinity to high affinity state
responsible for adhesion
how do neutrophils move through the interstitium
chemotaxis
movement along an increasing chemical gradient of chemoattractants:
-bacterial peptides, inflammatory mediators
-rearragement of neutrophil cytoskeleton
what is opsoniation
when the C3b and Fb protein bind to the the C3b receptor on the neutrophil
systemic complications of inflammation
fever NSAIDs leucocytosis malaise reduced appetite altered sleep tachycardia Acute phase proteins: C-reactive protein release septic shock
what happens after acute inflammation
complete resolution
repair with connective tissue- fibrosis
progression to chronic inflammation- prolonged inflammation with repair