This NCLEX review will discuss Heparin vs. Warfarin (Coumadin).
As a nursing student, you must be familiar with the differences and similarities between these two anticoagulants. This review will highlight how the medications work, nursing considerations, antidotes, and patient education.
Don’t forget to take the two quizzes that will test you on these medications:
Heparin vs. Warfarin Nursing Lecture
Similarities
Both are anticoagulants. They slow down the clotting process but do NOT break up an existing clot.
A patient can be on both of these medications at the same time until the patient’s INR level becomes therapeutic….then the Heparin will be discontinued.
Education pieces for both:
- No aspirin, NSAIDS or over-the-counter health supplements due to the risk of bleeding…always speak with MD before taking any new medications.
- Signs and symptoms of bleeding: bleeding gums, blood in stool (dark/tarry), blood in urine (red/pink urine), coffee ground emesis etc.
- No contact sports, use electric razors and soft bristle toothbrushes
- No IM injections
Differences
Heparin
Family Name: indirect thrombin inhibitors
- Enhances the activity of antithrombin III, which will inhibit thrombin and the conversion of fibrinogen to fibrin.
- Work on intrinsic pathway of coagulation: this pathway is normally activated by internal vascular trauma.
Onset: Fast
Duration: Short…stays in the system for hours
Administered:
- Injection (subcutaneous): administer 2 inches away from belly button, 1 inch away from scars, rotate injection sites, do NOT massage or rub area
- Intravenous: if on a continuous IV drip, the patient will be on a Heparin drip protocol, which will have very specific guidelines on how to titrate the drip to keep the patient’s clotting levels therapeutic.
It’s weight-based (always obtain a current and accurate weight for proper dosing). Here are some Heparin drip calculations for practice.
Monitor aPTT (activated partial thromboplastin time) :
- Normal aPTT: 30-40 seconds
- Therapeutic level for patients on Heparin: 1.5 – 2.5 times the normal range (about 60-80 seconds)
Less than 60 seconds: NOT therapeutic…may need an increase in rate and/or a bolus (depends on the Heparin protocol in place)
Greater than 80 seconds: at risk for bleeding…decrease rate and may need to turn off drip for a period of time (again depends on the Heparin protocol in place)
Antidote: protamine sulfate
Used for the short term
Can be used during pregnancy
- Watch for:
- Heparin-Induced Thrombocytopenia:
- HIT: occurs when antibodies develop against Heparin and platelet factor 4 complex.
- There will be a drop in platelets and new clots or worsening of current clots can occur.
- Heparin-Induced Thrombocytopenia:
Osteoporosis with long term/high doses of Heparin….because Heparin increases osteoclast activity and decreases osteoblast activity.
Warfarin
Family Name: Vitamin K antagonist
- Vitamin K helps make clotting factors in the liver.
- Since it’s a Vitamin K antagonist, it will work to inhibit clotting factors from using Vitamin K.
- Works on extrinsic pathway of coagulation: this pathway is normally activated by external trauma.
Onset: Slow (takes about 3-5 days for patient to become therapeutic)
Duration: Long…stays in the system for days
Administered:
- Orally via a pill
- Give at SAME time everyday
- Missed dose?
- Take when remembered if SAME day
- If remembered next day, skip the forgotten dose and take the regular scheduled dose. Be sure to make a note of the missed dose and let MD know.
Monitor PT/INR (prothrombin time/international normalized ratio)….The INR is calculated from the PT.
- Normal INR: 0.75-1.25 in a patient who is NOT taking Warfarin
- Therapeutic INR level for patients on Warfarin: 2-3
INR too low: not therapeutic…needs dose increased
INR too high: at risk for bleeding…needs dose decreased
Antidote: vitamin K
Used for the long term
Can NOT be used during pregnancy
Tell the patient to watch consuming too many foods high in vitamin K because they can decrease the INR level.
- This is mainly green leafy vegetables.
- Example: spinach, kale, broccoli, etc.
NO alcoholic beverage because this interferes with Warfarin.
References:
- Food and Drug administration. (2011). Warfarin sodium tablets Label Ebook]. Retrieved from https://www.accessdata.fda.gov/drugsatfda_docs/label/2011/009218s107lbl.pdf
- Food and Drug administration. (2017). Heparin Sodium, for intravenous use Ebook]. Retrieved from https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/017029s140lbl.pdf