1. Clotting Process: 2 pathways
    intrinsic and extrinsic pathway: factors activated by heparin and vitamin K dependent (Coumadin works there)
  2. intrinsic system
    requires certain clotting factors and calcium. activated by irritation or damage of endothelium (thrombophlebitis)
  3. extrinsic system
    clotting time is less bc body needs to hurridly clot the laceration or damaged tissue; requres thromboplastin
  4. anticoagulants
    • retard the clotting process. they DO NOT dissolve already formed clots, just PREVENT clots.
    • pt. teaching: minimize risk for injury
  5. Used primarily for prevention of clots in veins? (DVTs)
    • Heparin for initial anticoagulation;
    • Coumadin for maintainence
  6. Heparin
    can't be given orally since it can't cross the GI tract
  7. 1. thrombocytopenia
    2. thromboembolism
    • 1. decrease in platelets--->bleeding
    • 2. thromboembolism--->small clots
  8. ANTIDOTE: for heparin
    protamine sulfate if active hemorrhage
  9. labs to monitor
    • APTT (activated partial thromboplastin time)
    • Normal APTT=40 sec.
    • Therapeutic if 1.5-2X normal (60-80) (on sliding scale)
  10. low-molecular heparins
    • don't require APTT monitoring
    • most commonly used in orthopedic surgery
    • recommended in acute coronary syndrome
    • "parin" family
    • enoxaparin (Lovenox)
  11. Warfarin (Coumadin)
    • used as a rat killer
    • works on Vitamin K-dependent factors
    • maintenance anticoagulation drug
    • used for pre-a-fib, MI, artificial heart valve
  12. primary SE of Coumadin
    • hemorrhage
    • ANTIDOTE: Vitamin K
    • pt shouldn't eat too many green leafy vegis (spinach, etc.) since it contains vitamin K
  13. Labs to monitor
    • PT (prothrombin time-normal is 12)
    • Therapeutic level is 1 1/2X normal (18)
    • or INR w/ therapeutic level 2-3
  14. anti-platelet aggregates
    prevent arteriole clots
  15. thromboxane A2 inhibitors
    • bind to COX-1 receptors
    • Aspirin-82 mg recommended for pts w/ MI & stroke risk
    • 325 mg dose recommended as 1st line drug in management of pt w/ MI
    • BP needs to be no more than 150/90
  16. ibuprofin & aspirin
    shouldn't be taken together long term
  17. adenosine diphosphate receptor antagonists
    • prevent aggregation w/ irreversible blockade on platelets
    • used in pt who had a stroke or risk for stroke
    • cardic cath pt: clopidrogel (Plavix)
  18. glycoprotein IIb/IIIa receptor antagonists
    • block those receptors thereby preventing aggregation
    • most commonly used in acute coranary syndrome
    • abciximab (Reopro)
  19. Fibrinolytics
    • "clot busters"
    • primarily used in immediate MI
    • "ase" enzymes (form of tPA)
    • nurse determine: stroke bc of clot in vessel OR stroke bc of bleeding in brain before administering drug
  20. General criteria for fibrinolytics
    • window of opportunity: 6 hrs from onset (of symptoms for heart)
    • 3-4.5 hrs for stroke
    • over 80 y/o w/ previous hx stroke & DM: 3 hrs
    • no active bleeding-pt on Coumadin can get it but within 3 hr window & INR <1.7
    • no major trauma/surgery within last few months
  21. anti-fibrinolytic or hemostatic agents
    • promote clot formation
    • used to stop excessive bleeding
  22. blood
    • don't give it unless hemoglobin <10 g/dL
    • whole blood not usually givven (usually just certain component)
  23. cyroprecipitate "cryo"
    • precpitate after thaw plasma : fibrinogen
    • albumin: increases colloid osmotic pressure
  24. anemia
    • "ferrous": iron
    • vitamin C enhances absorption
    • antacids reduce absorption
  25. hematopoietic agents
    stimulates bone marrow to produce blood cells
  26. WBC stimulation
    • "grastim" drugs
    • platelet stimulation-- Neumaga
Card Set
hematology unit