Perfusion 4 Flashcards
Atherosclerosis: three reasons for cell damage
- Mechanical Stress (htn)
- Immune Response (high cholesterol and cytokines)
- Oxidative stress (free radicals)
Alcohol intake plays what part in HTN?
Alcohol is high in carbs. excess food is converted to triglycerides and stored as fats
High LDL is also known as
hyperlipidemia
High Cholesterol is also known as
hypercholesterolemia
Free radicals can cause oxidative stress in the form of:
- insulin resistance
- Decreased immunity
- aging
Antioxidants do what?
- reduce reactive molecules
- support normal cellular enzyme
Nicotine triggers ____ and increases ____
clotting and LDL
Clotting Cascade:
- Injury
- vascular spasm
- platelet plug formation
- platelet activation, release signal for aggregation (adenosine diphosphate, thromboxane A2, thrombin,_
- glycoprotein IIB/IIIA receptor activation makes them sticky
Prothrombin activator converts thrombin which leads to
fibrinogen converting to fibrin
Thrombin
- converts fibrinogen to fibrin
- activates factor XIII
- enhances platelet aggregation
- Facilitates its own synthesis
Narrowing of the vessel causes
Turbulent flow, ischemia
can cause CAD, Angina, PVD, HF
Vessel obstruction due to plaque can cause
ischemia, MI, HF, CVA
Thrombosis leading to emboli can cause
ischemia, DVT, PE, MI, CVA
Weakening of the vessel wall can lead to
aneurysm, hemorrhage, tamponade
3 drug classes for clotting tx
Antiplatelet (during platelet aggregation)
Anticoagulant (during coagulation cascade)
Thrombolytic (post clot formation)
Antiplatelet Meds
ASA, dipyridamole.
aggrenox: combo of ASA and dipyridamole
ASA - risk of bleeding through cox 2 inhibition
Clopidogrel (Plavix)
-block ADP in activation. good for kids (decreased platelet adhesion)
Abciximab (reopro), integrillin, aggrastat
-decreased fibrin receptor binding. expensive. good for pts receiving tx for decreasing blockage.
Baby Aspirin
Not actually for babies.
Recommended ASA dose for pain inflammation is 325-650mg)
recommended ASA for CV os 81 mg (aka baby sized aspirin)
only use for kids in Kawasaki syndrome (10-15mg)
Anticoaglulants
inhibit thrombin: heparin
-low molecular weight heparins: enoxaparin, daltaparin. pt can give themselves subcut. for DVT or PE prevention
Block thrombin receptors and factor IIa: dabigatran (prodrug) for stroke prevention
inhibit hepatic formation of clotting factors: warfarin (coumadin) long t1/2, high ppb, narrow ti. good for a fib pts
HIT Heparin induced thrombocytopenia
immune rx. to heparin
-leads to disseminated coagulation. up to 50% of pts on heparin get this, 3% fatal.
What is a prothrombin time test used to look at
body’s clotting time, to see how the body responds to the med.
Which two tests are used to see how fast the body clots
activated partial thromboplastin time and anti factor Xa levels.
Thrombolytics
Plasminogen in the blood gets converted to plasmin via tPA which lyses the clot.
med: tPA (altepase, reteplase)
t1/2 is 13-16 min, IV
Acute CAD
ACS
- unstable angina (with exertion the pt feels pain, wall between vessel and plaqu may rupture)
- risk of MI
- unstable plaque
Chronic CAD
Stable Angina
-thick fibrous plaque.
