Parsa -Embolism and Shock Flashcards
Can emboli that originates in the arterial circulation wind up in the venous circulation?
NO; thromboembolic is too large to permit passage through capillaries
where does systemic thromboembolic occur
in the arterial circulation; they can travel to a number of diff locations throughout the body–> lead to infarction.
where does systemic thromboemboli originate from
- left ventricular wall thrombi
- left atrial wall thrombi
- valvular vegetations
- thrombi on ulcertated atherosclerotic plaques or from aortic aneurysms.
what is paradoxical emboli
emboli that originate in the venous system, travel to the right heart and instead of making their way in to the lungs, they find a right to left heart passage in the wall between the atria or the ventricles. (septal defect)
where is the most common destinations of systemic emboli
- lower extremities
- brain
3, kidneys - spleen
what is the source of pulmonary thromboembolism
deep leg vein thrombosis; makes its way through the iliac veins, to the inferior vena cava and into the right heart. it then gets ejected into pulmonary arteries and lodges in a vessel downstream that corresponds to its size. When it lodges in the pulmonary artery bifurcation it is called saddle embolus and cause sudden death bc the right heart can’t pump blood past this obstacle
____ embolism occurs as a complication of long bone fractures in which fatty marrow is released into the bloodstream.
Fat
What are symptoms of fat emboli
- respiratory distress
- neurological symtoms
- thrombocytopenia
- anemia
- petechial rash
____ embolism is when necrotic, lipid debris inside an atherosclerotic plaque becomes an embolus following plaque rupture.
atheroma
what does atheroma embolism usually affect
small arteries affecting the
- kidneys
- spleen
- brain
- extremities
- intestines
____ fluid embolism refers to as a complication of labor and c section, through amniotic membrane rupture. Blood vessels get contested and get edema. It can cause respiratory distress, cyanosis, and collapse.
Amniotic
____ embolism refers to vascular occlusion to due to air/bubbles during delivery /abortion, accidental vascular trauma in pneumothorax, injury to chest, sudden changes in atmospheric pressure.
Gas
______ refers to inadequate blood supply to a tissue relative to its metabolic needs. It can be localized due to arterial or venous obstruction or generalized caused by cardiac failure.
Ischemia
_____ ischemia is mainly produced by arterial obstruction
Local
What are the main causes of arterial obstruction
- atherosclerosis
- thrombosis
- embolism
What are tissue changes resulting from arterial obstruction determined by
- availability of collateral circulation; venous has greater
- integrity of collateral arteries
- rate of development of obstruction
- tissue susceptibility to ischemia
- metabolic rate of the tissue
______ refers to an area of ischemic tissue necrosis caused by arterial or venous obstruction. Almost all cases of infarction result from ___ thrombosis or embolism.
infarction; arterial
When does infarction result from venous obstruction
- renal vein
- superior saggital sinus
- mesenteric veins
- venous torsion
what are the different colors/shapes of an infarction
- red or white
- wedge shape/irregular
- bland or septic
arterial blockage, and solid organs are usually a ____infart
pale
red infarcts occurs in all ____ infarcts, tissues possessing either a dual blood supply, or marginal collateral circulation.
venous
_____ is a clinical state ch. by prolonged systemic ___ resulting from insufficient cardiac output or reduction in the effective circulating blood volume .
shock; hypoperfusion
What are the 3 main types of shock
- hypovolemic
- cardiogenic
- shock by generalized vasodilation
_____ shock occurs from a sufficiently large reduction of intravascular blood volume. It can be caused by whole blood loss internally or externally, fluid loss due to voomitng or diarrhea or plasma loss due to burns
Hypovolemic
______ shock occurs from sort of heart pump failure resulting in a severe compromise of cardiac output, mostly associated with massive MI.
Cardiogenic
Shock by generalized vasodilation may occur in 3 different way:
- anaphylactic shock- severe allergic reaction
- neurogenic shock: may occur secondary to spinal cord trauma, brain injury, or the use of generalized anesthesia
- septic shock: infectious agents getting into bloodstream; mainly endotoxin producing gram negative bacilli
what are the 3 general stages of shock
- stage of compensation: sympathetic reflex compensatory mechanisms activated such as increased heart
- stage of impaired tissue perfusion (progressive stage): prolonged excessive vasoconstriction impairs tissue perfusion, resulting in hypoxia and impaired fluid exchange
- stage of decompensation: (irreversible); complete loss of reflex vasoconstriction; kidney failure; cardiac output failure, blood pressure drop to critical levels
what are thrombus prevention mechanisms
- aspirin (inhibits thromboxane A2)
- warfarin (antagonizes vitamin K)
- heparin (binds with antithrombin III)
- vitamin k deficiency
- streptokinase (act on thrombus already formed and break thrombus down)
fiber degradation products mean
thrombus is being broken down; associated with elevation of D dimer
what is being released in DIC
thromboplastin
what is happening during DIC
- PTT and PT prlonged
- fibrin degradation products elevated
- platelet levels are low
- small vessels become thromboses
