Anticoagulation & Blood D/O Flashcards
Warfarin MOA
Inhibits vit K oxide reductase enzyme complex →
* Inactive Factor II, VII, IX, X
Decrease protein C & S
Warfarin Mnemonic For Clotting Factors
SNOT
Seven
Nine
10
Two
Goal INR
For most Indication
2 - 3
Goal INR
Mechanic Mitral/heart Valves
2.5 - 3.5
Reasons to Initiate Lower Starting Doses of Warfarin
Elderly
Liver disease
Malnourished
Heart failure
Taking CYP inhibitors
Taking select antibiotics (penicillins, cephalosporins, quinolones, tetracyclines)
Warfarin
Boxed Warnings
Major or fatal bleeding
Warfarin
CI
Pregnancy
Except w/ mechanical heart valves at high risk for VTE
Warfarin
Warnings
Tissue necrosis/gangrene
Heparin-induced thrombocytopenia
Warfarin
SE
Bleeding/bruising
Skin necrosis (gangrene)
Purple toe syndrome
Warfarin
Antidote
Prothrombin complex concentrate
Fresh frozen plasma
Vit K (delayed reversal)
A nurse practitioner wishes to convert a patient from warfarin to dabigatran. She asks the pharmacist how to manage the conversion. The pharmacist should offer the following advice:
A. Discontinue warfarin and start dabigatran when the INR is below 2.5.
B. Discontinue warfarin and start dabigatran when the INR is below 2.
C. Discontinue warfarin and start dabigatran when the INR is at or below 1.5.
D. Stop warfarin and initiate dabigatran the following morning.
E. Discontinue warfarin and start dabigatran when the INR is below 3.
Discontinue warfarin and start dabigatran when the INR is below 2.
Warfarin Drug Intxn
CYP2C9 Inducers
↓ Warfarin serum levels → ↓ INR
Warfarin Drug Intxn
CYP2C9 Inhibitors
↑ Warfarin serum levels → ↑ INR
Warfarin Drug Intxn
CYP2C9 Inducers Mnemonic
Review Pt Profiles & Counsel Soon
Rifampin
Phenytoin
Phenobarbital
Carbamazepine
St. John’s wort
Non CYP2C9 inducers that causes ↓ warfarin effects: green leafy vegetables
Warfarin Drug Intxn
CYP2C9 Inhibitors Mnemonic
AAA
Amiodarone
Azole antifungals (eg, fluconazole, ketoconazole, voriconazole)
Select Anti-infectives (ie, metronidazole, Bactrim)
Other meds that ↑ Warfarin effect but are not CYP2C9 inhibitors: some antibiotics
* quinolones
* tetracyclines
Warfarin Drug Intxn
↑ risk of bleeding
NSAIDs
Antiplatelet agents (eg, P2Y12 inhibitors: clopidogrel, ticagrelor)
Anticoagulants
SSRIs/SNRIs
Warfarin Drug Intxn
↑ clotting risk
Estrogen
SERMs
Warfarin Dietary Supplement Intxn
↑ risk of bleeding
Chamomile
Chondroitin
Dong quai
High doses of fish oils
Vitamin E
Willow bark
5G’s: garlic, ginger, ginkgo, ginseng, glucosamine
Warfarin Tablet Colors
Please Let Greg Brown Bring Peaches To Your Wedding
1 - Pink
2 - Lavender
2.5 - Green
3 - Brown/tan
4 - Blue
5 - Peach
6 - Teal
7.5 - Yellow
10 - White
Conversion between anticoagulants
Warfarin to DOACs
READ
Rivaroxaban < 3
Edoxaban ≤ 2.5
Apixaban < 2
Dabigatran < 2
INR
Sickle cell disease is a qualifying condition for which of the following vaccines? (Select ALL that apply)
A. Haemophilus influenzae type B vaccine
B. Hepatitis B vaccine
C. Pneumococcal vaccine
D. Meningococcal vaccine
E. Varicella vaccine
Haemophilus influenzae type B vaccine
Pneumococcal vaccine
Meningococcal vaccine (Bexsero, Trumenba)
The spleen plays a unique role in clearing pathogens from the body.
Because the spleen can be damaged (i.e., afunctional) due to repeated vaso-occlusive crises, sickle cell disease patients are at higher risk of infections, especially from encapsulated bacteria (e.g., S. pneumoniae, N. meningitidis, H. influenzae).
For this reason, vaccination with Haemophilus influenzae type B (HiB), pneumococcal, and meningococcal vaccines is recommended.
Hepatitis B vaccine and varicella vaccine are routine childhood vaccinations that are administered to all patients regardless of the presence of underlying conditions.
Which of the following signs or symptoms exhibited by this patient are consistent with iron deficiency anemia? (Select ALL that apply)
A. Bradycardia
B. Fatigue
C. Glossitis
D. Heartburn
E. Pallor
F. Shortness of breath
Fatigue
Glossitis
Pallor
Shortness of breath
Iron deficiency anemia diagnosis
Signs & symptoms
Fatigue, weakness, shortness of breath, exercise intolerance, pallor
Glossitis (ie, inflamed, sore tongue)
Koilonychia (ie, spoon-shaped nails)
Pica (ie, eating nonfoods such as ice or clay)
Iron deficiency anemia diagnosis
Laboratory findings
↓ Hgb, MCV (ie, microcytic anemia)
↓ Reticulocyte count, serum iron, ferritin, TSAT
↑ TIBC
Iron deficiency anemia
Tx
Oral iron supplement (eg, ferrous sulfate, ferrous fumarate): 1 tablet once daily or every other day
Causes of Anemia
Impaired RBC or Hgb production
↑ RBC destruction (hemolysis)
Blood loss
Anemia
S/S
Fatigue/ weakness
SOB
Exercise intolerance
HA/Dizziness
Pallor
Iron Deficiency Anemia
S/S
Glossitis (swollen or inflamed tongue)
Koilonychia (indented shape nails, like a spoon)
PIca (eats things that aren’t ususally food)
Vitamin B12 Deficiency
S/S
Neuropathy
Visual disturbance
Psychatric symptoms
MCV < 80 fL
Microcytic
Iron deficiency
MCV 80-100 fL
Normocytic
CKD, blood loss, aplastic anemia, hemolysis
MCV > 100 fL
Macrocytic anemia
Vitamin B12 or folate deficiency
Which intervention is most likely to increase the absorption of the newly prescribed medication?
A. Administer with vitamin C.
B. Separate administration from Lexapro.
C. Switch to ferrous sulfate.
D. Take with docusate.
E. Use a sustained-release formulation.
Administer with vitamin C.
Iron is best absorbed in an acidic gastric environment; therefore, coadministration with vitamin C (ascorbic acid) improves iron absorption.
Oral iron supplementation
Administration
1 tablet once daily or every other day
Take on an empty stomach
Oral iron supplementation
Adverse effects
Constipation
Dark, tarry stools
Nausea
Oral iron supplementation
Drug interactions
↓ Iron absorption by ↑ gastric pH
↑ Iron absorption by ↓ gastric pH
Chelated by iron (and absorption decreased) if administered concomitantly
Oral iron supplementation: Drug interactions
↓ Iron absorption by ↑ gastric pH
Antacids,
H2RAs,
PPIs
Oral iron supplementation: Drug interactions
↑ Iron absorption by ↓ gastric pH
Ascorbic acid (vitamin C)
Oral iron supplementation: Drug interactions
Chelated by iron (and absorption decreased) if administered concomitantly
Fluoroquinolone and tetracycline antibiotics
Bisphosphonates
Levothyroxine
Integrase strand transfer inhibitors
Separate administration from iron (eg, by 2–4 hours) to avoid interaction.
Oral iron supplementation
Monitoring
Hemoglobin: can ↑ after 1–2 weeks
Iron panel: can take 3–6 months for ferritin to normalize
Factor Xa
Direct:
Rivaroxaban
Apixaban
Edoxaban
Indirect:
Fondaparinux (antithrombin)
Apixaban (Eliquis)
Stroke PPx in Nonvalvular Afib
5 mg PO BID
Apixaban (Eliquis)
Stroke PPx in Nonvalvular Afib
Reason for dose adjustment & dose
Age ≥ 80 y/o
Body wt ≤ 60 kg
SCr ≥ 1.5 mg/dL
Dose: 2.5 PO BID
Apixaban (Eliquis)
Tx of VTE
Initial: 10 mg PO BID x 7d
Followed by 5 mg PO BID
Rivaroxaban (Xarelto): Stroke PPX in Nonvalvular AFib
CrCl > 50
20 mg PO QD w/ evening meal
Rivaroxaban (Xarelto): Stroke PPX in Nonvalvular AFib
CrCl 15-50
15 mg PO QD w/ evening meal
Rivaroxaban (Xarelto): Stroke PPX in Nonvalvular AFib
CrCl < 15
Avoid use
Rivaroxaban (Xarelto): Tx of VTE
Dose
Intial 15 mg PO BID x 21d
then 20 mg PO QD w/ food
Rivaroxaban (Xarelto): Tx of VTE
CrCl < 30
Avoid use
Edoxaban (Savaysa)
Stroke PPX in Nonvalvular AFib
CrCl > 95 do not use
Edoxaban (Savaysa)
Tx of VTE
Start 60 mg PO QD after 5-10d of parenteral anticoagulation
Missed dose
apixaban & edoxaban
Take immediately on the same day
Then resume normal scedule
Don’t double dose
Missed dose: Rivaroxaban
15 mg BID
Take immediately
2 tablets may be taken at once
Missed dose: Rivaroxaban
10, 15, 20 mg QD
Take immediately on the same day
Otherwise skip the missed dose
Oral Factor Xa
Boxed Warnings
Patients receiving neuraxial anesthesia (epidural, spinal) or undergoing spinal puncture are at risk of hematomas and paralysis
Premature discontinuation increases risk of thrombotic events
Oral Factor Xa
Contraindications
Active pathological bleeding
Oral Factor Xa
Warnings
Not recommended with prosthetic heart valves or antiphospholipid syndrome
Oral Factor Xa
Side Effects
Bleeding
Oral Factor Xa
Monitoring
No routine monitoring for efficacy
Can monitor for safety:
Hemoglobin, hematocrit, SRc, liver function tests
What is the antidote to apixaban & rivaroxaban?
andexanet alfa (Andexxa)
Fondaparinux (Arixtra)
Boxed Warnings
Patients receiving neuraxial anesthesia (epidural, spinal) or undergoing spinal puncture are at risk of hematomas and paralysis
Fondaparinux (Arixtra)
Contraindications
Severe renal impairment (CrCl < 30 mL/min),
Major active bleeding,
Bacterial endocarditis,
Thrombocytopenia with positive test for anti-platelet antibodies in presence of fondaparinux
Fondaparinux (Arixtra)
Side Effects
Bleeding,
Anemia,
Local injection site reactions,
Thrombocytopenia
Factor Xa Inhibitor, Direct Thrombin Inhibitors, & Heparin Drug Intxn
Additive bleeding risk
Anticoagulants
Antiplatelets
NSAIDs
SSRIs
SNRIs
Factor Xa Inhibitor Drug Intxn
Apixaban & Rivaroxaban
Major 3A4 substrate
P-gp
With strong inhibitors of 3A4 or P-gp
Apixaban ↓ dose if take > 2.5 mg PO BID otherwise do not use
Rivaroxaban: do not use
Steps for conversiont from Oral Xa inhibitor to warfarin
Stop Xa inhibitor
Start parenteral anticoagulant & wafarin at next scheduled dose
Which of the following is an appropriate treatment for a vaso-occlusive crisis in sickle cell disease?
A. Morphine
B. Aspirin
C. Levofloxacin
D. Loperamide
E. Enoxaparin
Morphine
Vaso-occlusive crises are episodes of acute, severe pain from sickled blood cells blocking blood flow, which leads to decreased oxygen and ischemia in the tissues.
IV opioids, including PCA, are needed for the severe pain associated with vaso-occlusive crises.
Medications:
Prinzide
Lopressor
Coumadin
Glucophage
Victoza
PW complains that her back pain is worsening and wants to take Advil or Doan’s for pain relief. The pharmacist should provide the following counseling:
A. It is safe to take either Advil or Doan’s with other medications. They are both available over the counter.
B. Do not take Advil but it is safe to take Doan’s for pain relief. If symptoms do not improve, contact a healthcare provider.
C. Do not take Doan’s but it is safe to take Advil for pain relief. If symptoms do not improve, contact a healthcare provider.
D. It is not safe to take either Advil or Doan’s while on warfarin.
E. The patient will need to see her healthcare provider for her pain. There are no safe, over the counter options to manage her pain.
It is not safe to take either Advil or Doan’s while on warfarin.
Both ibuprofen (Advil) and magnesium salicylate (Doan’s) are non-steroidal anti-inflammatory medications and are not recommended for use with warfarin due to an increased risk of bleeding.
Both are popular OTC products.
Acetaminophen is the analgesic of choice when a patient is on warfarin.
Hypercoagulable risk factors
BMI ≥ 30
age ≥ 40
VTE Prevention
Long distance travel
Calf muscle exercises
Frequent ambulation
Sitting in an aisle seat (on an airplane) when possible
With at least one VTE risk factor: below-the-knee graduated compression stockingsr
Risk factors for venous thromboembolism (VTE)
Modifiable
Acute medical illness
Immobility
Medications
* ESAs
* Estrogen-containing
* SERMs
Obesity (BMI ≥ 30 kg/m2)
Pregnancy & postpartum
Recent surgery or trauma (knee & hip)
Risk factors for venous thromboembolism (VTE)
Nonmodifiable
Increasing age
* > 40 for nonorthopedic surgical hospitalized pts
* ≥ 70 fior nonsurgical hospitalized pts
Cancer
Heart failure
Known thrombophilia
* Antiphospholipid syndrome
* Antithrombin deficiency
* Factor V Leiden mutation
* Protein C or S deficiency
Previous VTE
Respiratory failure
Direct Thrombin inhibitors
IV: Argatroban, bivalirudin (Angiomax)
Oral: Dabigatran (Pradaxa)
Direct Thrombin inhibitors
Affects what factors?
IIa
Dabigatran Indications
Tx & prevention of VTE
* start after 5-10d of parenteral anticoagulation
Stroke PPx in pts w/ nonvalvular AFib
PPx of VTE following hip replacement surgery
Dabigatran (Pradaxa)
Boxed Warnings
Patients receiving neuraxial anesthesia (epidural, spinal) or undergoing spinal puncture are at risk of hematomas and paralysis
Premature discontinuation increases risk of thrombotic events
Dabigatran (Pradaxa)
Contraindications
Active pathological bleeding, patients with mechanical heart valves
Dabigatran (Pradaxa)
Side Effects
Dyspepsia,
Gastritis-like symptoms,
Bleeding (including Gl bleeding)
What is the antidote for dabigatran?
idarucizumab (Praxbind)
How is dabigatran dispense?
In the original container
Discard bottle after 4 months after opening
How to take dabigatran?
Swallow capsules whole (do not break, chew, crush, or open)
Do not administer by nasogastric tube
Missed dose:
Take immediately unless it is w/in 6 hrs of the next scheduled dose.
Do NOT double dose
Injectable Direct Thrombin Inhibitors Indications
Argatroban
Heparin-induced thrombocytopenia (HIT)
In patients with or at risk for HIT that are undergoing percutaneous coronary intervention (PCI)
Injectable Direct Thrombin Inhibitors Indications
Bivalirudin (Angiomax)
In patients undergoing PCI, including those at risk for HIT
Injectable Direct Thrombin Inhibitors
Contraindications
Major active bleeding
Injectable Direct Thrombin Inhibitors
Side Effects
Bleeding (mild to severe), anemia
Injectable Direct Thrombin Inhibitors
Monitoring
aPTT and/or activated clotting time, platelets, hemoglobin, hematocrit. kidney function
Injectable Direct Thrombin Inhibitors
What is the antidote?
None
Safe to use in patients with HIT; no cross-reaction with HIT antibodies
?
Converstion of dabigatran to warfarin
Start warfarin 1-3 days before stopping dabigatran
Unfractionated heparin MOA
Binds to antithrombin (AT)
inactivate thrombin (factor IIa) & Xa
Unfractionated heparin
Prophylaxis of VTE
5,000 units SC Q8-12H
Unfractionated heparin
Treatment of VTE
80 units/kg IV bolus; 18 units/kg/hr infusion
Use total body weight
Unfractionated heparin
Treatment of ACS/STEMI
60 units/kg IV bolus; infuse at 12 units/kg/hr
Use total body weight
Unfractionated heparin
Contraindications
Uncontrolled active bleed
History of heparin-induced thrombocytopenia
Hypersensitivity to pork products
Unfractionated heparin
Warnings
Fatal medication errors: verify the correct concentration is chosen
Unfractionated heparin
Side Effects
Bleeding, thrombocytopenia, hyperkalemia, osteoporosis (with long-term use)
Unfractionated heparin
Heparin lock-flushes (HepFlush)
10 or 100 units/mL
Enoxaparin (Lovenox) Dosing
Prophylaxis of VTE
30 mg SC Q12H or 40 mg SC daily
CrCl < 30 mL/min: 30 mg SC daily
Enoxaparin (Lovenox) Dosing
Treatment of VTE and Unstable Angina/NSTEMI
1 mg/kg SC Q12H or 1.5 mg/kg SC daily
CrCl < 30 mL/min: 1 mg/kg daily
Use total body weight
Enoxaparin (Lovenox) Dosing
Treatment of STEMI in Patients < 75 Years of Age
30 mg IV bolus plus a 1 mg/kg SC dose followed by 1 mg/kg Q12H
CrCl < 30 mL/min: 30 mg IV bolus plus a 1 mg/kg dose, followed by 1 mg/kg SC daily
Use total body weight
Enoxaparin (Lovenox) Dosing
Treatment of STEMI in Patients ≥ 75 Years of Age
0.75 mg/kg SC Q12H (no bolus)
CrCI < 30 mL/min: 1 mg/kg SC daily
Use total body weight
