Acute inflammation Flashcards
What is acute inflammation?
series of protective changes occurring in living tissue as a response to injury. fundamental response maintaining integrity of organism
What are the cardinal signs of inflammation?
redness, heat, swelling, pain, loss of function
What are the causes of acute inflammation?
microorganisms, trauma ie injury to tissue, chemical (upset stable environment), physical (extreme conditions eg frostbite), dead tissue, hypersensitivity
What is the sequence of events constituting acute inflammation?
series of microscopic events, localised to affected tissue, take place in the microcirculation, result in clinical symptoms and signs of acute inflammation
What are the benefits of acute inflammation? 5
rapid response to non specific insult, cardinal signs and loss of function gives transient protection of inflamed area, neutrophils destroy organisms and denature antigen for macrophages, plasma proteins localise process, resolution and return to normal
microcirculation
capillary beds- fed by arterioles and drained by venules, extracellular space, lymphatic channels. fluid moves into tissue using dynamic balance. increased permeability due to change in membrane capacity to hold back hydrostatic pressure. increased viscosity, decreased flow
exudation
net movement of plasma from capillaries to extravascular space. oedemas (accumulation of fluid in extravascular space) formed
outcomes of acute inflammation
resolution, suppuration, organisation, chronic inflammation
what is the role of the neutrophil in acute inflammation
they are mobile phagocytes, release granule contents which possess oxidants and enzymes and destroy foreign antigen.. neutrophils die when granule content released and this produces pus
what are the mediators of acute inflammation
molecules on endothelial cell membrane, molecules released form cell, molecules in plasma, molecules inside cells.
what are the systemic effects of acute inflammation
pyrexia, feel unwell, neutrophilia, lymphadenopathy, weight loss, anaemia
what are the functions of mediators of acute inflammation
They cause vasodilation, increase permeability, neutrophil adhesion, chemotaxis, itch and pain
what are the functions of mediators of acute inflammation
They have positive and negative effects and the result is a dynamic balance. Favours and inhibits acute inflammation. cause vasodilation, increase permeability, neutrophil adhesion, chemotaxis, itch and pain
suppuration
pus formation, pyogenic membrane surrounds pus, abscess sometimes (multiloculated-pus bursts through pyogenic membrane and forms new cavities)
organisation
granulation tissue characteristic, healing and repair, leads to fibrosis and formation of a scar
