Circulation II Flashcards
Define the process of thrombosis.
Thrombosis: the result of activation of the clotting mechanism within the cardiovascular system, in a living person
Can seal a rupture or be inappropriate
Understand the difference between thrombosis and hemostasis.
Thrombosis: pathologic process; inappropriate intravascular clotting in a living person
—Clot formation on UNINJURED epithelium
Hemostasis: normal process; blood maintained clot-free; hemorrhage is stopped by sealing blood vessels after rupture
Discuses the most encountered cases of thrombosis. (4)
- Ventricular mural thrombosis: caused by injury to endocardium and decreased flow following an MI
- Thrombosis of heart valves: caused by endothelial injury due to infective endocarditis, rheumatic (autoimmune) endocarditis, or trauma -> hypercoagulable states
- Venous thrombosis:
- -Phlebothrombosis: due to stasis of blood in uninflamed veins, sometimes aggravated by hypercoagulability
- -Thrombophlebitis: thrombosis in inflamed veins, due to trauma, radiation, chemicals, or bacteria
- -Parts can break off -> pulmonary embolism - DIC (discussed in other lectures)
Define the outcomes of thrombosis, particularly venous thrombosis. (4)
Lysis (dissolution) = resolution
Organization in connective tissue
Propagation towards the heart
Embolization to lungs
Define the process of embolism and its clinical outcomes.
Embolism: obstruction of an artery by a detached mass carried by the bloodstream to a distant site from its point of origin
Causes: blood clot, atheroma, fat, bone marrow, tumor, air, foreign substances
Outcomes: differ if systemic vs pulmonary circulation
—Potentially -> infarction
Discuss the causes and clinical outcomes of thromboembolism.
Cause: part of a dislodged thrombus, generally from leg -> pulmonary circulation
Outcomes:
- Silent small pulmonary emboli
- Sudden death from large pulmonary emboli
- Hemorrhage in lungs from medium sized emboli
- Infarction of lower extremities
- Stroke
Discuss the causes and clinical outcomes of cholesterol embolism.
Cause: atherosclerotic debris
Outcomes: ischemia
Discuss the causes and clinical outcomes of decompression sickness.
Cause: bubbles of oxygen or nitrogen -> physical obstruction of arteries/atria; from diving, obstetric procedures, or large chest trauma
Outcomes:
- Pain
- Focal ischemia
- Trouble breathing
-Persistence -> Caisson disease -> focal necrosis in skeletal system
Discuss the causes and clinical outcomes of fat embolism.
Cause: droplets of fat that enter circulation and obliterate an artery; from fractures, trauma, or burns
Outcomes:
- Usually silent
- Severe if in brain or lungs and big enough
Discuss the causes and clinical outcomes of amniotic embolism.
Cause: amniotic fluid/fetal masses enter maternal circulation during labor or immediately after
Outcomes:
-20-40% mortality rate
List a possible cause of foreign body embolism.
Cause: things like bits of bullets
Define shock as a cardiovascular disorder.
Inadequate perfusion of cells and tissues
Due to decreased ECV and/or decreased CO
Discuss the three progressive phases of shock pathogenesis.
- Nonprogressive/compensated: compensatory mechanisms maintain CO and BP, enabling perfusion of heart and brain
- Progressive, still reversible: generalized hypoperfusion and worsening of circulatory and metabolic imbalances
- Irreversible: severe tissue/cellular injury -> multiple organ failure and death even in the conditions of correction of hemodynamic defects
Name the types of shock encountered in clinic and discuss the causes. (5)
Hypovolemic shock: hemorrhage, diarrhea, dehydration, burns
Cardiogenic shock: MI, myocarditis, cardiac tamponade, pulmonary embolus
Anaphylactic shock: Type 1 HS
Neurogenic shock: brain damage, spinal cord injury, anaesthesia accidents
Septic shock: severe infection
Define clotting.
Coagula that form outside of blood vessels or in blood vessels postmortem
