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
Which meds should patients on heparin avoid taking ?
Aspirin, NSAIDS, OTC herbals without talking to physician because it can affect bleeding times
Precautions for patients on Heparin or Warfarin
Aspirin, NSAIDS, OTC herbals without talking to physician because it can affect bleeding times
No contact sports (risk for bleeding)
Use electric razors and soft bristle tooth brush
Teach patients S/S of bleeding - look at gums - is there oozing of blood? Any pinkish/reddish urine? Dark, tarry stool? Coffee grounds vomiting ?
Avoid IM injections because of bleeding risk
Your patient is started on a Heparin drip. You administer a bolus of Heparin and start the drip per protocol as ordered by the physician. What will be your next important nursing action?*
Collect an aPTT level in 6 hours per protocol.
A patient is ordered to start an IV continuous Heparin drip. Prior to starting the medication, the nurse would ensure what information is gathered correctly before initiating the drip?*
Weight
“It enhances the activation of antihrombin III, which prevents the activation of thrombin and the conversion of fibrinogen to fibrin.
Heparin
In Heparin therapy, the nurse would want to make sure the documented ___________ of the patient is current and accurate.
weight
This medication is weight-based. Therefore, for proper dosing to be administered, a correct weight should be used.
Any aPTT value greater than ___________-seconds places the patient at risk for bleeding
80
11. A patient is on a continuous IV Heparin drip. As the nurse you are monitoring for any adverse reactions. Select all the signs and symptoms that would indicate this patient is having an adverse reaction to this medication: A. Hematuria B. Decreasing platelets C. Increased blood glucose D. Low hemoglobin and hematocrit E. Positive stool guaiac test
The answers are A, B, D and E. Hematuria, low hbg/hct and positive stool guaiac test all indicate the patient is bleeding. A decrease in platelet level could indicate the patient is developing Heparin-induced thrombocytopenia, which is also an adverse reaction to Heparin.
What happens in HIT ?
HIT is where the body makes antibodies against Heparin because it’s binding to platelet factor 4 (a blood protein). This creates antibodies that will bind to the heparin and PF4 complex, which activate the platelets. Small clots will form (hence new clots or worsening of clots) and the platelet count falls…hence thrombocytopenia.
A patient develops Heparin-Induced Thrombocytopenia (HIT). As the nurse, you would expect the Heparin to be discontinued and the patient to be started on what other type of anticoagulant?
A. Direct thrombin inhibitor
B. Protamine sulfate
C. Switched to subcutaneous Heparin injections
D. Vitamin-K agonist
The answer is A. The Heparin is discontinued and direct thrombin inhibitors can be started like: Argatroban, Bivalirudin etc.
4. Warfarin (Coumadin) affects the formation of certain clotting factors. Select below ALL the clotting factors this medication affects: A. I B. V C. II D. VII E. XI F. X G. IX
The answers are: C, D, F, and G. Warfarin (Coumadin) affects FOUR clotting factors that require vitamin K to form. These clotting factors are: 2, 7, 9, and 10 (II, VII, IX, X)
Your patient was started on Warfarin (Coumadin) a week ago for the treatment of a DVT. Which findings below would indicate an adverse reaction to this medication? Select all that apply:
A. Patient reports a severe and sudden headache
B. Melena
C. Chvostek’s Sign
D. Hematuria
E. Coffee ground emesis
F. Bleeding gums
The answers are A, B, D, E, and F. An adverse reaction would be associated with bleeding. Patients who take Warfarin should be monitored for signs and symptoms that bleeding is occurring internally. Example would be: sudden/severe headache (represents intracranial bleed), melena (dark, tarry stools…represent blood), hematuria (urine reddish or pink), coffee ground emesis (bleeding in the stomach), or bleeding gums….along with tachycardia, hypotension, nosebleeds, or bruising for no reason. Chvostek’s Sign is associated with a low calcium level (hypocalcemia).
A patient, who is taking Warfarin (Coumadin), asks what he should do if he misses a dose. Your response would be:
Take the dose when remembered, if on the same day. However, if not remembered on the same day but the next day, skip the missed dose and take the next dose at the regular scheduled time
