Pages 186-191: Med Surg Flashcards
why is the inflammatory response necessary?
neutralizes and dilutes the inflammatory agent, removes necrotic materials, and establishes an environment suitable for healing and repair
inflammation and infection
inflammation is always present with infection, but infection is not always present with inflammation (can be caused purely by heat, radiation, trauma, chemicals, rather than just infection)
vascular response step one
after cell injury, artioles briefly vasoconstrict
vascular response step two
histamine is released, vessels dialate, which causes hyperemia (increased blood flow to injured site)
vascular response step three
increased capillary permeability causes fluid to move from capillaries to tissue
vascular response step four
exudate is initially composed of serous fluid and plasma proteins, which exert oncotic pressure and further draw fluid from blood vessels causing edema
vascular response step five
when protein fibronogen leaves the blood, fibrin is activated, which strengthens clots
why are clots important to tissue?
traps bacteria, prevents their spread, framework of healing process
chemotaxis
directional migreation of WBCs to site of injury
cellular response via neutrophils
arrive to injury site within 6-12 hours and phagocytize bacteria; only live 24-48 hours
what do dead neutrophils produce?
pus
bands
immature neutrophils released due to bone marrow relasing more neutrophils into circulation and infection getting worse
shift to the left
when band neutrophils are increasing due to acute bacterial infections or progressive infections in general
cellular response via monocytes
arrive 3-7 days after onset of inflammation and transform into macrophages, which clean the area before healing can occur; long life span
multinucleated giant cell
particles are too large for a single macrophage and they accumulate, then encapsulate in collagen, causing formation of granuloma (small area of inflammation)
prostaglandins
produced from arachidonic acid and cause vasodilation (producing increased blood flow and edema PROINFLAMMATORY); can also act as pyrogen
complement system
enzyme cascade c1-c9 mediate inflammation and destroy invading pathogens through phagocytosis, increased vascular permeability, chemotaxis, and cellular lysis
c8 & c9
final components of complement system that pierce the cell and lyse
thromboxane
causes brief vasoconstriction and skin pallor at the injury site and promotes clot formation- short half life and gives way to prostaglandins and histamines vasodilation
leukotrienes
slow reacting anaphylaxis, which constricts smooth muscule of bronchi and stimulates chemotaxis
local response
redness, heat, pain, swelling, loss of fx
systemic response
increased WBC with shift to left, malaise, nausea, increased pulse and respirations, fever
systemic response possibly caused by
complement activation and cytokines
fever
onset is due to cytokines, hypothalamus stimulates ANS to promote shivering, and epinephrine released from the adrenal medulla increases the metabolic rate
benefits of fever
increased killing of microorganisms, increased phagocytosis from neutrophils, increased proliferation of T cells
acute inflammation
healing occurs in 2-3 weeks usually with no damage, neutrophils are predominant
subacute inflammation
same as acute, but inflammation lasts longer
chronic inflammation
may last for years, injurious agent persists or repeats injury to site, lymphocytes and macrophages dominant
when should fever be treated rapidly?
if 104+ or immunosuppressed patient
Aspirin
Salicylates lower the temperature, interfere with prostaglandins, and reduce capillary permeability; selectively depress CNS
Tylenol
acetominophen lower the temperature
NSAIDs
ibuprofen, motrin, advil inhibit synthesis of prostaglandins and reduce fever
corticosteroids
interfere with granulation tissue and induce immunosuppressive effects and reduce fever
Rest (RICE)
repair process is facilitated by allowing fibrin and collagen to form across the wound edges with little disruption
Ice (RICE)
ice used initially and heat used later around 24-48 hours
Compression (RICE)
counters the vasodilation effects and development of edema, asses distal pules and capillary refill before and after devices are placed
Immobilization
promotes healing by decreasing metabolic needs of the tissues
Elevation (RICE)
elevate above the level of the heart to reduce edema by increasing venous and lymphatic return; contraindicated in patients with reduced arterial circulation
