Heparin vs Warfarin Flashcards
This med enhances the activity of antithrombin III- this inhibits thrombin in order to stop the conversion of fibrinogen to fibrin. It works on the intrinsic pathway of coagulation, so whenever there is internal trauma to the vascular system
Heparin
this med is part of the family of indirect thrombin inhibitors
Heparin
this med belongs to the family of vitamin K antagonist
Warfarin
Vitamin K is used in the liver to make _____________-
clotting factors
_________ inhibits clotting factors from using vitamin K
Warfarin
Which pathway does Warfarin work on ?
Extrinsic pathway of coagulation, activated when there is external trauma
Heparin and Warfarin are both ______ - they slow down the clotting process in different ways
anticoagulants
They are not used to break/lysis a clot
rather they are used to prevent/treat blood clots
comment on the onset of heparin to Warfarin………
Heparin has FAST onset compared to Warfarin (takes 3-5 days to get to therapeutic levels)
Once INR gets to therapeutic levels using Warfarin, heparin will be weaned off
How long does Heparin stay in the system compared to Warfarin ?
Heparin stays in for hours. Warfarin stays in for days
How is Heparin administered ? What should you remember about the injection procedure?
Subcutaneous injection - goes into the fatty tissue.
2 inches away from navel. 1 inch away from scars. Rotate injection sites. Don’t massage or rub.
Intravenously- (continuous)
What lab value do we monitor for Heparin ?
aPTT (activated partial thromboplastin time)
Heparin dosing is based on
weight
normal aPTT and therapeutic levels
30-40 seconds
Therapeutic: 1.5-2 times the normal, around 60 seconds
How is Warfarin administered ?
Only PO
take at same time every day
If dose is missed: If remembered same day, take the dose
If remembered next day, skip previous dose and take scheduled dose due that day. Write it down what day they missed and let MD know
With Warfarin, what lab do we monitor ?
INR
normal INR is 0.75-1.25
Therapeutic levels: 2-3
Heparin antidote
Protamine Sulfate
Warfarin antidote
Vitamin K
Heparin is usually used ______term while Warfarin is used _________ term
short; long
Can heparin be used during pregnancy ?
YES
Can Warfarin be used during pregnancy?
NO
Watch out for this side effect with Heparin
HIT
Heparin induced Thrombocytopenia (HIT)
characterized by reduced platelet counts (thrombocytopenia) and a seemingly paradoxical increase in thrombotic events
What is Heparin induced Thrombocytopenia characterized by and what is the main cause ?
characterized by reduced platelet counts (thrombocytopenia) and a seemingly paradoxical increase in thrombotic events
underlying cause is development of antibodies against heparin-platelet protein complexes. These antibodies activate platelets and damage the vascular endothelium, thereby promoting both thrombosis and a rapid loss of circulating platelets
If a patient is on heparin for long term and at a high dose, watch out for
osteoporosis
Osteoporosis can occur due to long-term, high doses of Heparin. Bone fractures would indicate this patient is experiencing this complication. Heparin can stimulate osteoclasts and inhibits osteoblast, which affects the strength of the bones.
What to remember about diet with Warfarin ?
Avoid excessive intake of green leafy vegetables- broccoli, spinach, kale - these foods are high in vitamin K, which can lower the INR level to non therapeutic levels
Also, alcohol interferes with Warfarin so avoid alcohol