hemodynamic disorders II Flashcards
infarction
1) area of ischemic necrosis
2) occlusion of vessel
3) embolus or thrombus which occludes it
- necrosis and cell death at the site (infarction)
arterial thrombosis
1) most of the infarctions are attributed to it
2) depends on the anatomy of arterial supply, time it develops, and vulnerability of the tissue, and how much blood oxygen content1
venous occlusion
1) typically in spongy tissues like lungs
- red / hemorrhagic
2) or pale / white
- dense tissues
3) arterial occlusion and compact tissue
4) depends on the same things
dual supply
1) obstruction of pulmonary arteries does not always mean infarction of the lungs bc there is other supply
2) also the liver, which has hepatic artery and the portal vein
3) and the hand and forearm, which has radial and ulnar artery
4) ALLEN tests!!!!
allen test
1) should blanch if you occlude the radial and ulnar
2) then when you release one, the hand should flush back
3) if not, it is a negative test
- you should not do an A-line
kidney and spleen
1) end arterial circulation
2) obstruction of one is more likely to cause infarction
rate of occlusion
1) slowly developing occlusions are less likely to cause infarction
tissue vulnerability to ischemia
1) neurons undergo irreversible damage when deprived of blood supply for only 3 to 4 minutes
hypoxemia
1) abnormally low blood O2 content increases both the liklihood and extent of infarction
white infarcts
1) occlusion is in solid organs with end arteriolar circulation !!!***
2) wedge shaped and clear demarcation
3) lateral margins may be irregular
4) the acute infarctions are indistinct
red and white in lungs
ischemic coagulation necrosis
1) liquefactive or coagulative
2) different parts of the body with have either type of necrosis
- brain: ischemia with liquefactive necrosis
3) inflammation along margins => few hours should start being sharply demarcated
regeneration of parenchymal tissue
1) can occur at the periphery of the infarct, whether they can regenerate and replace with scar tissue
septic infarctions
1 )cardiac valve damaged (vegetation of clot can break and embolize or stay and occlude with necrosis)
2) need dental clearance before they replace their valve
shock !!!***
1) pathophysiological state
2) decreased tissue perfusion and hypoxia!!!!
3) three types
- septic, hypovolemic, and cardiogenic
4) massive blood loss, myocardial infarction, sepsis
5) initially reversible, but can lead to irreversible injury (fatal)
cardiogenic shock
1) low CO due to heart pump being inadequate
2) MI can also cause it
3) ventricular arrythmia
4) cardiac tymponade
5) outflow obstruction problems
hypovolemic shock
1) loss of blood or plasma
2) hemorrhage or burn
septic shock
1) arteriolar dilation and venous blood pooling
2) from immune response
shock (uncommonly)
1) loss of vascular tone and General anesthesia
2) reversible
anaphylactic shock
1) vasodilation and systemic Vasopermeability
2) IgE (type I)
treatment for shock
1) IV fluid hydration (except for cardiogenic shock)
2) you’d have to increase the CO
- and give O2
septic shock
1) host response to bacteria or fungus
2) endothelial cell activation
- coagulation cascade
3) vasodilation
4) edema
5) DIC
- clotting and bleeding
6) metabolic dearrangment
20% mortality
- decrease in muscle tone and intravascular coagulation
pathway for septic shock
1) gram + (most common) and gram - follow it
2) innate and hummoral system
- macrophages and cytokines
3) inflammatory cells
4) vasopermeability
5) complement cascade and anti-coagulation
6) systemic inflammatory response syndrome
- MULTIPLE SYSTEMS
inflammatory mediators
1) what cells they’re activating (KNOW THIS)
endothelial cell activation and injury
1) thrombosis
2) increased vascular permeability
3) vasodilation
