Anticoagulants: prevent formation of clots
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Action:
o
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Prevents new clots from forming
Use:
o
DVT
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PE
o
MI
o
Artificial heart valves
o
Stroke
Anticoag
Heparin
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Action:
o
Bind with antithrombin III
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Inhibit action of thrombin
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Inhibit conversion of fibrinogen to fibrin
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Inhibit clot formation
Use:
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Most commonly to prevent venous thrombosis
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Acute PE
Administration of heparin:
o
SQ
o
IV
Heparin lab values:
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PTT (1.5-2 times control value (control 60-70 seconds))
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aPTT (30-85 seconds (control 20 to 35 seconds))
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Xa
Side effects:
o
Bleeding
o
Heparin induced thrombocytopenia
Antidote:
o
Protamine sulfate
Low Molecular Weight Heparin
(Lovenox)
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Action:
o
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Inactivates Xa factor
Use:
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Prevent DVT
o
Acute PE after surgery
Why LMWH vs normal heparin?
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Lower risk of bleeding
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Frequent lab monitoring is not required
Precautions:
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Don’t take aspirin concurrently
Oral Anticoags
Warfarin (Coumadin)
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Action:
o
Inhibits hepatic synthesis of vitamin K

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Use:
o
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Prevent thromboembolic conditions of thrombophlebitis, PE, and embolism formation
Lab values:
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INR (2-3) unless pt has a mechanical heart valve (2.5-3.5)
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Frequent checks to maintain therapeutic range
Side effects:
o
> 3 = bleeding
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< 2 = clotting
Interactions:
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MANY food and drug interactions (EDUCATE)
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Green, leafy vegetables
Antidote:
o
Vitamin K for overdose

o
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Affects clotting factors II, VII, IX, and X
Takes 24-48 hours to be effective
For acute bleeding, fresh frozen plasma, or platelets
GOOD TO KNOW!!
o
Long half-life
o
Still needs protection while they wait
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Once INR is therapeutic, discontinue bridge therapy
Nursing Process for Heparin and Warfarin
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Assessment:
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Obtain a history of abnormal clotting or health problems affecting clotting
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Gather a drug history including complementary and alternative therapy history
Planning:
o
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The patient will not have excess bleeding
Nursing interventions:
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Monitor PT, INR for Warfarin, monitor aPTT for Heparin
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Examine patient’s nose, urine, mouth, and skin for bleeding
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Teach patient to inform dentist when taking an anticoag
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Advise patient to use a soft toothbrush to prevent bleeding gums
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Advise patient to avoid large amounts of green, leafy vegetables or be consistent with intake
Direct Thrombin Inhibitors
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Action:
o
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Directly inhibit thrombin from converting fibrinogen to fibrin
Use:
o
Prophylaxis and treatment of DVT and PE
o
Thrombus prophylaxis for HIT, unstable angina, A-FIB and stroke
Administration:
o
IV
o
SQ
Antiplatlets: suppress platelet aggregation
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Used:
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Prevent thrombosis in the arteries
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Prevention of myocardial infarction or stroke for patients with familial history
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Prevention of a repeat myocardial infarction or stroke
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Prevention of a stroke for patients having transient ischemic attacks
Antiplatelets
Aspirin
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Action:
o
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Inhibit cyclooxygenase, an enzyme needed by platelets to synthesize thromboxane A2
Use:
o
Prevention of MI, thromboembolism, prevention, and treatment of stroke
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GOOD TO KNOW!!
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Effective and inexpensive treatment for suppressing platelet aggression
Thrombolytics: attack and dissolve clots that have already formed
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Examples:
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Aspirin (Bayer)
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Clopidogrel (Plavix)
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Adenosine diphosphate (ADP) antagonist

Frequently used after MI or stroke

Used with aspirin for more effective results
Action:
o
Bind to fibrinogen promoting conversion of plasminogen to plasmin
o
Plasma digests fibrin in a clot and degrades fibrinogen, prothrombin, and other clotting factors
Use:
o
-

Prevention of MI or stroke
Side effects:
o
Anaphylaxis
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Dysrhythmias
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Hemorrhage
GOOD TO KNOW!!
o
Long action… stop 7 days before surgery
o
Avoid excessive foods that may cause bleeding (garlic)