U2: Anti-Coagulant Drugs Flashcards
How do anticoagulants function?
Inhibits clog formation and prevents new clots from forming
What are the four classes of anticoagulant drugs?
Heparin, warfarin, low molecular weight heparins and factor Xa inhibitors
How is heparin dispensed? (What route?)
Sub Q or IV
How is warfarin dispensed? (What route?)
Oral
Which anticoagulant is used prophylactically to prevent thrombus or to treat acute thrombus, usually in the hospital?
Heparin
Which anticoagulant is used for established patients?
Warfarin
Which anti-coagulant has a longer half-life?
Warfarin
Which anti-coagulant is highly protein bound, which can heighten adverse effects?
Warfarin
What are side effects of heparin?
Itching, chills, headache, nosebleeds, vomiting blood, skin redness, hematoma, alopecia, elevated hepatic enzymes, N/V, injection site reaction, priapism
What are contraindications for heparin?
Heparin-induced thrombocytopenia, hypersensitivity
Patients with which conditions should use caution when taking heparin?
Peptic ulcer, hepatic or renal disease, hemophilia, disseminated intravascular coagulation, diverticulitis, head trauma, asthma, aneurism, endocarditis, thrombocytopenia, pregnancy/breastfeeding, older adults.
What are adverse effects of heparin?
Bleeding, intracranial bleeding, ocular hemorrhage, anemia, bone fracture, osteoporosis, hyperkalemia, vitamin d deficiency, GI bleeding, stroke, hyperlipidemia, thrombocytopenia, heparin-induced thrombocytopenia, anaphylaxis
Which drugs interact poorly with heparin?
Increased effect: Aspirin, NSAIDs, thrombolytics, probenecid, antibiotics, SSRI
Decreased effect: nitroglycerin, protamine sulfate (antidote)
Which lab monitors the effect of heparin and what is the normal range?
PTT (Partial thromboplastin time). 60-70 seconds
What is the antidote for heparin?
Protamine sulfate
What are the side effects of warfarin?
Headache, alopecia, fever, weakness, priapism, petechiae, ecchymosis (discoloration of the skin)
What are adverse effects of warfarin?
Purple toe syndrome, bone fracture, hypotension, angina, hematuria, ocular hemorrhage, intracranial / vaginal / GI bleeding and hemorrhage.
What are contraindications for warfarin?
Pregnancy, hematologic disorders, eclampsia, alcohol abuse, stroke, bleeding, head trauma, aneurism
Patients with which conditions should use caution when taking warfarin?
Type 2 diabetes (DM), leukemia, anemia, thyroid disease, hepatic and renal impairment, peptic ulcer, atrial fibrillation, heart failure, cerebrovascular disease, breastfeeding
What are drug interactions of warfarin?
Increased effects: aspirin, NSAIDs, sulfonamides, thyroid drugs, allopurinol, histamine 2 blockers, oral hypoglycemics, metronidazole, miconazole, methyldopa, diuretics, oral antibiotics, vitamin E
Decreased effects: Barbituates, laxatives, phenytoin, estrogen, vitamin C, vitamin K, oral contraceptives, rifampin
Would a smoker get an increased or decreased dose of warfarin?
Increased
Which lab monitors the effect of warfarin and what is the normal range?
INR (International Normalized Ratio)
Normal: 1.3 - 2
With anticoagulant: 2-3
With prosthetic heart valves: up to 3.5
What is the antidote for warfarin?
Vitamin K (Dietary restriction on leafy greens, etc.)
What are the names of low molecular weight heparins?
Enoxaparin (Lovenox) and Dalteparin (Fragmin)
Low molecular weight heparins are give via what route?
Sub Q
What should you observe for in patients using low molecular weight heparins or Factor Xa inhibitors?
Petechiae, bruising, tarry stools and other signs of bleeding
What are contraindications for low molecular weight heparins?
Stroke, peptic ulcers, brain / spinal surgeries
What medications should be avoided with low molecular weight heparins?
Aspirin and other NSAIDs
Why are low molecular weight heparins or Factor Xa Inhibitors preferable?
Less monitoring than warfarin or heparin, produces more stable results with less bleeding risk
What education should you provide for patients using low molecular weight heparins or Factor Xa Inhibitors?
Look for signs of bleeding and use a soft bristle toothbrush
What are the names of Factor Xa Inhibitors?
Rivaroxaban (Xarelto) and Apixaban (Eliquis)
What is the antidote for Factor Xa inhibitors?
Andexanet Alfa
Factor Xa Inhibitors are given via what route?
Oral
Should you continue/discontinue Factor Xa Inhibitors for surgery?
Discontinue 1-2 days prior
What is the weight limit for Factor Xa Inhibitors?
less than 50 kg
