Arrhythmias And Venous Thromboembolism

Front 1

What is the MOA/ Indication for Class 1a drugs?
(antiarrhythmic medications)

Back 1

Sodium Channel Blockers

Na+ channel blockers; Slow conduction velocity & repolarization

Indication: Supraventricular & ventricular arrhythmias

Front 2

What is the MOA/ Indication for Class 1b drugs?
(antiarrhythmic medications)

Back 2

Sodium Channel Blockers

Weak Na+ channel blockers (not very potent antiarrhythmics)

Indication: Ventricular & supraventricular arrhythmias (more effective w/ventricular arrhythmias)

Front 3

What is the MOA/ Indication for Class 1c drugs?
(antiarrhythmic medications)

Back 3

Sodium Channel Blockers

Potent Na+ channel blockers; Eliminate reentry by slowing conduction to the point where impulse is halted

Indication: Supraventricular arrhythmias

Front 4

What is the MOA/ Indication for Class II drugs?
(antiarrhythmic medications)

Back 4

Beta Blockers

Affect slow-channel tissue (SA & AV nodes); decreases rate of automaticity, slows conduction velocity (most effective in tachycardic arrhythmias), prolong refractoriness

Indications: Sinus tachycardia, atrial fibrillation, atrial flutter, ventricular fibrillation

Front 5

What is the MOA/ Indication for Class III drugs?
(antiarrhythmic medications)

Back 5

Potassium Channel Blockers

K+ channel blockers; Prolong refractoriness in atrial & ventricular tissue
Amiodarone also blocks Na+ channels (fast kinetics), **nonselective beta-blocking actions, ***some Ca+ blocking actions

Indications: Supraventricular & ventricular arrhythmias

Front 6

What is the MOA/ Indication for Class IV drugs?
(antiarrhythmic medications)

Back 6

Calcium Channel Blockers (Non DHP)

Block Ca+ channels; Slows conduction, prolongs refractoriness, decreases automaticity

Indications: Supraventricular tachyarrhythmias

Front 7

Class 1a antiarrhythmics are treated with what type of drug?

Give an example?

Back 7

Sodium Channel Blockers

Quinidine, procainamide, disopyramide

Front 8

Class 1b antiarrhythmics are treated with what type of drug?

Give an example?

Back 8

Sodium Channel Blockers

Lidocaine, mexiletine

Front 9

Class 1c antiarrhythmics are treated with what type of drug?

Give an example?

Back 9

Sodium Channel Blockers

Propafenone, flecainide, moricizine

Front 10

Class II antiarrhythmics are treated with what type of drug?

Give an example?

Back 10

Beta Blockers

Metoprolol, esmolol, atenolol

Front 11

Class III antiarrhythmics are treated with what type of drug?

Give an example?

Back 11

Potassium Channel Blockers

Amiodarone, sotalol, dofetilide, ibutilide

Front 12

Class III antiarrhythmics are treated with what type of drug?

Give an example?

Back 12

Calcium Channel Blockers (Non DHP)

Diltiazem, verapamil

Front 13

What is the MOA/ Indication for low molecular weight heparins (LMWH)?

Back 13

Binds to AT-III to produce anticoagulant effect

Indications: Prophylaxis of thromboembolism, STEMI, ischemia

Ex: Dalteparin (Fragmin)
Enoxaparin (Lovenox)
Tinzaparin (Innohep)

Front 14

What is the MOA/ Indication for Factor Xa?

Back 14

Synthetic pentasaccharide that causes AT-III inhibitor of Factor Xa to prevent thrombin formation

For treatment & prophylaxis of thromboembolism

Ex:Fondaparinux (Arixtra)

Front 15

What is the MOA/ Indication for Warfarin (Coumadin)?

Oral Anticoagulation

Back 15

MOA: Stops conversion of vitamin K epoxide to active vitamin K --> Lack of activated clotting factors II, VII, IX, X and Protein C & S

Indications: Treatment (in conjunction w/heparin or LMWH or fondaparinux for 1st several days. It takes a while to be effective.) & prophylaxis of thromboembolism, atrial fibrillation, cardiac valves

Front 16

Will Amiodarone increase or decrease INR when used with Warfarin?

Back 16

Increase

Front 17

Will ETOH (acute use) increase or decrease INR when used with Warfarin?

Back 17

Increase

Front 18

Will aspirin increase or decrease INR when used with Warfarin?

Back 18

Increase

Front 19

Will NSAIDs (Ibuprofen, naproxen, etc) increase or decrease INR when used with Warfarin?

Back 19

Increase

Front 20

Will Celecoxib (Celebrex) increase or decrease INR when used with Warfarin?

Back 20

Increase

Front 21

Will antibiotics increase or decrease INR when used with Warfarin?

Bactrim, Flagyl, Cephalosporins, Fluoroquinolones, Erythromycin, Tetracycline, etc

Back 21

Increase

Front 22

Will Fluconazole (Diflucan) increase or decrease INR when used with Warfarin?

Back 22

Increase

Front 23

What type of drug do you use to treat 2nd and 3rd degree heart blocks?

Back 23

None!
Potentially Fatal

Front 24

Where are all Na+ channel blockers metabolized?
Antiarrhythmics Class I

Back 24

Hepatic (P450)

Front 25

When treating a patient with:
Sinus tachycardia, Atrial Fibrillation,
Atrial Flutter, or Ventricular Fibrillation

What type of drug would you administer?

Back 25

Antiarrhythmic Class II Drugs

Beta Blockers
Metoprolol, esmolol, atenolol

Front 26

Recap!

What do we know about Selective Beta 1 Blockers?

Back 26

Adrenergic Antagonist (block sympathetic response)
The neurotransmitters blocked include:
Biogenic Amines/ Catecholamines/Epinephrine and Norepinephrine

Selective Beta 1 Blockers include:
Metoprolol (Lopressor, Toprol XL), atenolol (Tenormin), acebutolol (Sectral), esmolol (Brevibloc)

Hypertension Treatment…..vasodilation

Class II/ III Heart Failure…..blocking sympathetic response; A sympathetic response puts a lot of demands on the heart “It expects great output” to deal with fight or flight situations.

1st agent for Ischemic Heart Disease… Reduces myocardial oxygen demand, decrease HR, BP, and contractility

Antiarrhythmic Class II for sinus tachy, AFib, Aflutter, and VFib (Metoprolol, esmolol, atenolol
)…..Affect SA/AV Node and decrease rate of automaticity and conduction velocity

Front 27

Class I, III, IV antiarrhythmics all treat supraventricular arrhythmias, which also treat ventricular arrhythmias?

Back 27

Class Ia/Ib and Class III

Note: Class Ib are not very potent antiarrhythmics, but are more effective with ventricular arrhythmias. (Lidocaine, Mexiletine )

Front 28

What type of drugs are
Antiarrhythmics Class Ia ?

Back 28

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Indicated with Supraventricular & ventricular arrhythmias

Front 29

What type of drugs are
Antiarrhythmics Class Ib ?

Back 29

Sodium Channel Blockers
Lidocaine, Mexiletine

Indicated with Supraventricular & ventricular arrhythmias (more effective with ventricular arrhythmias)

Front 30

What type of drugs are
Antiarrhythmics Class Ic ?

Back 30

Sodium Channel Blockers
Propafenone (Rhythmol), Flecainide, Moricizine

Indicated with Supraventricular arrhythmias

Front 31

What type of drugs are
Antiarrhythmics Class II ?

Back 31

Beta 1 Blockers
Metoprolol, Esmolol, Atenolol

Indicated with Sinus tachycardia, atrial fibrillation, atrial flutter, ventricular fibrillation

Front 32

What type of drugs are
Antiarrhythmics Class III ?

Back 32

Potassium Channel Blockers
Amiodarone, Sotalol, Dofetilide (Tikosyn), Ibutilide (Corvert)

Indicated with Supraventricular & ventricular arrhythmias

Front 33

What type of drugs are
Antiarrhythmics Class IV ?

Back 33

Calcium Channel Blockers
Diltiazem, Verapamil

Indicated with Supraventricular arrhythmias

Front 34

Antiarrhythmics Class I: Na+ Blocker

MOA

Back 34

Class Ia- Na+ channel blockers; Slow conduction velocity & repolarization

Class Ib- Weak Na+ channel blockers (not very potent antiarrhythmics)

Class Ic- Potent Na+ channel blockers; Eliminate reentry by slowing conduction to the point where impulse is halted

Front 35

Antiarrhythmics Class I: Na+ Blocker

Pharmacokinetics

Back 35

Class Ia- Intermediate kinetics

Class Ib- Fast (Express effects only at fast heart rates)

Class Ic- Slow (Express effects at all heart rates)

Front 36

Antiarrhythmics: Class Ia

Back 36

Quinidine
ADE’s: N/V/D, cinchonism (tinnitus, CNS effects), HF exacerbation, hypotension, TdP
Drug Intxns: Warfarin (increase INR), digoxin, amiodarone

Procainamide
ADE’s: *Lupus-like syndrome (SLE), hypotension, HF exacerbation, TdP
Drug Intxns: Fluoroquinolones, amiodarone, Bactrim, TCA’s
Avoid in renal & hepatic dysfnxn****

Disopyramide (Norpace)
ADE’s: Anticholinergic (tachycardia, constipation, dry eyes, urinary retention), HF exacerbation, TdP
Drug Intxns: CytP450 3A4 inhibitors, fluoroquinolones
Notes: Caution in glaucoma*** like all anticholinergics

Front 37

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

All Class Ia drugs have a possible adverse effect of heart failure exacerbation and/ or cause torsades, but which drug can possibly cause cinchonism?

Back 37

Quinidine

Cinchonism is caused by an overdose of quinine and can cause tinnitus and CNS effects like blurred vision, impaired hearing, confusion, etc.

Note: quinine can also be found in tonic drinks as the bittering agent

Front 38

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

All Class Ia drugs have a possible adverse effect of heart failure exacerbation and/ or cause torsades, but which drug can possibly cause a Lupus like syndrome (SLE?

Back 38

Procainamide

Front 39

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

All Class Ia drugs have a possible adverse effect of heart failure exacerbation and/ or cause torsades, but which drug can possibly cause anticholinergic effects?

Back 39

Disopyramide (Norpace)

remember anticholinergic effects include tachycardia, constipation, dry eyes, and urinary retention.

All anticholinergics should be avoided in patients with glaucoma

Front 40

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with Warfarin; increasing INR?

Back 40

Quinidine

Front 41

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with the efficacy of Fluoroquinolones?

Back 41

Procainamide and Disopyramide (Norpace)

Front 42

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with Amiodarone (K+ channel blocker)?

Back 42

Quinidine and Procainamide

Note: procainamide also interacts with Bactrim

Front 43

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with tricyclic antidepressants (TCAs)?

Back 43

Procainamide

Front 44

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug should be avoided with patients who have renal or hepatic dysfunction?

Back 44

Procainamide

Front 45

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with Digoxin a glycoside used to treat AFib, Aflutter, and heart failure?

Back 45

Quinidine

Front 46

Antiarrhythmics: Class Ia

Sodium Channel Blockers
Quinidine, Procainamide, Disopyramide (Norpace)

Which drug interacts with CytP450 3A4 inhibitors (ex: erythromycin, azole antifungals, CCB nondhp)

Back 46

Disopyramide (Norpace)

Front 47

Antiarrhythmics Class Ib
Lidocaine, Mexiletine

Which is contraindicated in 3rd degree heart blocks?

Back 47

Both

Front 48

Antiarrhythmics: Class 1b
Indicated in Ventricular, Supraventricular arrhythmias

Lidocaine & Mexiletine

Both meds can cause CNS effects; which is responsible for peri-oral numbness, seizures, confusion, blurry vision, tinnitus, muscle twitching, sedation, slurred speech, and even psychosis.

This drug will slow the heart rate down, but can make you CRAZY!

Back 48

Lidocaine

note: Mexiletine can cause N/V, GI upset, dizziness, confusion, anxiety, tremor

Front 49

Antiarrhythmics: Class 1b
Indicated in Ventricular, Supraventricular arrhythmias

Lidocaine & Mexiletine

Both interact with phenytoin and fluoroquinolones, but which also interacts with theophylline a drug used to treat respiratory distress (COPD/ Asthma)?

Back 49

Mexiletine

Note: Lidocaine also interacts with amiodarone (K+ channel blocker/Class II) and beta blockers (Class III)

Remember Phenytoin interacts with all Class 1 drugs because it is an enzyme inducer and reduces their efficacy.

Front 50

Lidocaine & Mexiletine

What class antiarrhythmics do these meds belong to and when would they be indicated?

Back 50

Antiarrhythmics: Class 1b
Indicated in Ventricular, Supraventricular arrhythmias
(more effective with ventricular arrhythmias)

Weak Na+ blocker
Fast Kinetics/ Express effects at fast heart rates

Front 51

Antiarrhythmics: Class 1c
indicated in Supraventricular Arrhythmias

Propafenone (Rhythmol) & Flecainide

both can exacerbate heart failure, but which can cause the patient to have a metallic taste, feel dizzy and fatigued, and possibly experience bronchospasms?

Back 51

Propafenone (Rhythmol)

note: Flecainide can cause the patient to feel dizzy, blurred vision, dyspnea, and tremors

Front 52

Antiarrhythmics: Class 1c
indicated in Supraventricular Arrhythmias

Propafenone (Rhythmol) & Flecainide

both interact with Digoxin, but which drug causes and increased [Digoxin] concentration of 70%?

What type of symptoms would the patient exhibit?

Back 52

Propafenone (Rhythmol)


Digoxin is used to treated AFib, AFlutter, and sometimes heart failure.

Dig tox can cause a patient to experience N/V, Confusion, Blurred Vision, See Halos, New Arrhythmias, and/or PVCs

note: Flecainide will increase [Digoxin] by 25%.

Front 53

Antiarrhythmics: Class 1c
indicated in Supraventricular Arrhythmias

Propafenone (Rhythmol) & Flecainide

both interact with digoxin and SSRIs, but which drug interacts with tricyclic antidepressants (TCAs) with an increase risk of torsades?

Back 53

Flecainide

Front 54

Antiarrhythmics: Class 1c
indicated in Supraventricular Arrhythmias

Propafenone (Rhythmol) & Flecainide

Which drug is contraindicated for a patient with coronary artery disease (CAD)?

Back 54

Flecainide

Front 55

Choosing an antiarrhythmic!

This drug affects slow channel tissue (SA and AV nodes); decreases rate of automaticity and slows conduction of velocity.

It is most effective in tachycardic arhythmias (sinus tachy, AFib, Aflutter, VFib) and prolongs refractory.

Back 55

Beta Blockers
(Metoprolol, esmolol, atenolol)

Class II arrhythmias

Front 56

This drug blocks potassium, sodium, some calcium, and provides nonselective beta blocking actions all in one!

Back 56

Amiodarone

K+ channel blockers
Class III Antiarrhythmics

Front 57

This drug is used most often to treat arrhythmias, but can cause pulmonary fibrosis, hypothyroidism, neurologic toxicity, hypotension, torsades, optic neuritis, photosensitivity, N/V/C, and increase LFTs.

Back 57

Amiodarone

K+ channel blockers
Class III Antiarrhythmics

Note: amiodarone has a long 1/2 life and symptoms can show up long after administration.

Remember Amiodarone is metabolized in liver (CYP 450 3A4), causing so many ade.

Front 58

This drug could cause your patient to turn blue-gray.

Back 58

Amiodarone

K+ channel blockers
Class III Antiarrhythmics

Front 59

What drugs interact with Amiodarone?

Back 59

Warfarin (increased INR)

Digoxin (1/2 dose)

Statins (rhabdomyolysis)

Grapefruit Juice (inhibition)

Phenytoin (enzyme inducing/dec. efficacy)

Front 60

What other drugs are Class III antiarrhythmics?

Back 60

K+ channel blockers

Sotalol, Dofetilide, Ibutilide

Front 61

Which Class III antiarrhythmic can exacerbate heart failure, cause torsades and lead to bradycardia and wheezing?

Remember that all Class 1 antiarrhythmics can also exacerbate heart failure and torsades. (Na+ chan.blocker)

Back 61

Sotalol

Front 62

What drugs interact with Sotalol?

(K+ channel blocker/ Class III antiarrhythmic)

Back 62

Class 1 drugs (remember same ade)

Tricyclic antidepressants (TCAs)

Fluroquinolones

Clonidine (alpha 2 agonist)
used for hypertension, insomnia, adhd, and tourettes

Front 63

Which other antiarrhythmics also interact with TCAs?

Back 63

Class 1a (Procainamide)

Class 1c (Flecainide)

Class III (Sotalol, Ibutilide)

Front 64

Which antiarrhythmics are contraindicated with a prolonged QT interval?

Back 64

Class III Antiarrhythmics
K+ Channel Blockers

Dofetilide (Tikosyn) and Ibutilide (Corvert)

Front 65

Which Class III antiarrhythmic interacts with Hydrachlorthiazides, Verapamil, and Fluroquinolones?

This drug is also metabolized in the liver (CYP450 3A4 ) like amiodarone.

Back 65

Dofetilide (Tikosyn): new

Note: better tolerated than amiodarone, but very expensive and harder to approve; ade only include dizziness, diarrhea, toursades, and chest pain.

Front 66

True or False

All Class I/ III antiarrhythmics can cause torsades.

Back 66

True

Sodium and Potassium
channel blockers

Front 67

The MOA for this group of drugs blocks Ca+ channels, slows conduction, and prolongs refractory; decrease automaticity.

When are they indicated?

Back 67

Calcium Channel Blockers (NonDHP)

Diltiazem and Verapamil

Indication: Supraventricular Tachyarrhythmias

Front 68

This drug inhibits Na-K+ ATPase-->Increases intracellular Na concentration-->Increased intracellular Ca concentratio-->Positive inotropic effect, decreased sympathetic response & decreased renin-angiotensis system output

Indications: AFIB/AFlutter

Back 68

Digoxin (Lanoxin)

1-3 hours peak

Front 69

Digoxin is metabolized in the liver (Cyt450-dependent) and has active metabolites which account for long 1/2 life and numerous adverse effects.

What type of ADEs are seen?

Back 69

Diarrhea

Loss of Appetite

Nausea and Vomiting

Headache/ Visual disturbances

Cardiac Dysrhythmias/ PVCs

Front 70

What drugs interact with Digoxin?

Back 70

Verapamil (increase intracellular Ca+)

Amiodarone

Thiazides

Quinidine

Azoles

Macrolides

Front 71

When is Digoxin absolutely contraindicated?

Back 71

Ventricular Fibrillation

Heart is one beat/ fibrillation away from asystole and digoxin inhibits sympathetic response

Front 72

MOA: Binds to antithrombin III to form a complex that inactivates clotting factors II (thrombin), XII, IXa and Xa, preventing conversion of fibrinogen to fibrin and the formation of new thrombi

Back 72

Hepariin

note: can be administered SubQ and IV; rapid absorption and widely distributed

Front 73

This drug is recommended for treatment/ prophylaxis of thromboembolism as well as Atrial Fibrillation.

Back 73

Heparin

Front 74

Which drug reverses the effects of Heparin?

Back 74

Protamine Sulfate

(forms inactive protamine-heparin complex)

note: just 1mg of protamine can neutralize 100 units of heparin (slow reversal/ infusion)

Front 75

This anticoagulant can cause bleeding, thrombocytopenia, and skin necrosis.

Back 75

Heparin

If thrombocytopenia is going to occur it will do so typically within 5-10 days; stop heparin once platelets are lower than 100,000. (HIT)

If this occurs heparin nor any LMWH can ever be administered

Front 76

If Heparin cause "HIT" and a patient's platelets drop below 100,000 what can be prescribed as an alternative treatment?

Back 76

Argatroban

Front 77

This medication is not a LMWH, but is treated like one. It can be used in the presence of HIT!

Back 77

Fondaparinux (Arixtra)

Front 78

These drugs are indicated for prophylaxis of thromboembolism, STEMI, and ischemia.

Back 78

Low Molecular Weight Heparins (LMWH) & Factor Xa Inhibitor

Dalteparin (Fragmin)
Enoxaparin (Lovenox)
Tinzaparin (Innohep)

Front 79

These drugs are unable to bind to thrombin very effectively, but do bind to AT-III to produce anticoagulant effects.

Back 79

Low Molecular Weight Heparins (LMWH) & Factor Xa Inhibitor

Dalteparin (Fragmin)
Enoxaparin (Lovenox)
Tinzaparin (Innohep)

Front 80

Who has a longer 1/2 time life heparin or LMWH?

Back 80

Low Molecular Weight Heparins (LMWH) & Factor Xa Inhibitor

Dalteparin (Fragmin)
Enoxaparin (Lovenox)
Tinzaparin (Innohep)


note: must be adjusted in patients with renal inefficiencies.

*Contraindicated when CrCl <30mL/min, because of increased bleeding risk (will continue if benefit outweighs risk)

Front 81

Heparin or LMWH

Which is contraindicated in obesity?

Back 81

LMWH

Contraindicated in obesity (>150kg), because of LMW it is not distributed as widely/ Less effective than heparin (injected into abdominal tissue/ less distributed with excess FAT)

Front 82

True or False

LMWH is ok to use when a patient has experienced HIT.

Back 82

False

absolute contraindication

(alternative:Argatroban and Fondaparinux (Arixtra))

Front 83

True or False

LMWH risk of bleeding is decreased due to small molecular size.

Back 83

False

approximately same risk

Remember Protamine can reverse heparin, but it can only reverse enoxaparin!

note: 1mg protamine : 1mg enoxaparin***

Front 84

Which drug is only a Factor Xa Inhibitor?

Back 84

Fondaparinux (Arixtra)

administered SubQ

Front 85

LMWH has a longer 1/2 life (4hrs) than Heparin, but which drug has a 1/2 life of 17- 21 hours and lends well to once daily dosing!

Back 85

Fondaparinux (Arixtra)

This drug is eliminated renally and could last even longer when a patient has renal dysfunction.

Front 86

Which anticoagulants are contraindicated <30 renal function?

Back 86

LMWH/ Factor Xa Inhibitor
Dalteparin (Fragmin)
Enoxaparin (Lovenox)
Tinzaparin (Innohep)

Factor Xa Inhibitor
Fondaparinux (Arixtra)

Front 87

Which anticoagulant is contraindicated in patients who weight

>150 kg

<50 kg

Back 87

>150 kg (LMWH)

<50 kg Fondaparinux (Arixtra)

Front 88

Note:

Back 88

LMWH or Factor-Xa Inhibitor v. Heparin

Easier dosing **once daily available
Less lab monitoring (lmw and FXA)
Can be used at home* (heparin cannot)
Unknown effects in renal insufficiency & obesity (Heparin is o.k. here)
More expensive (LMW and Factor xa)

Front 89

This anticoagulant can be give oral, IV and PO. It is dosing equivalent IV/PO. It is also a Vitamin K antagonist.

Back 89

Warfarin (Coumadin)

Front 90

MOA: Stops conversion of vitamin K epoxide to active vitamin K -->Lack of activated clotting factors II, VII, IX, X and Protein C & S

Back 90

Warfarin (Coumadin)

Indications: Treatment (in conjunction w/heparin or LMWH or fondaparinux for 1st several days. It takes a while to be effective.) & prophylaxis of thromboembolism, atrial fibrillation, cardiac valves

Front 91

LMWH has a longer 1/2 life (4hrs) than Heparin and Fondaparinux has an even longer 1/2 life (17-21hrs) and can be given once daily.

Warfarin's T1/2 life is 20- 60 hours, but what is its drawback?

Back 91

Onset 36-72 hrs
Effect 5-7 days
SS-10-14 days

It is rapidly absorbed but it does take time to become effective and will take adjustments for proper dosing.

Front 92

Which anticoagulant has the greatest incidence of bleeding?

Back 92

Warfarin (2.4 to 29%)
including epistaxis,GI bleeds, bleeding gums, hematuria

2.8% chance of a fatal bleed

Front 93

Which anticoagulant has the severest form of necrosis at the site of injection and why?

Back 93

Warfarin

Significant thrombosis of venules & capillaries within SubQ fat tissue (abdomen, buttocks, thighs, breasts)
Occurs due to deficiency in Proteins C & S
Typically occurs by Day 10 of therapy initiation
Tx—Temporarily stop warfarin (initiate heparin/LMWH) and gradually restart & titrate warfarin

Front 94

What is purple toe syndrome?

Back 94

Systemic cholesterol microembolism resulting from release of atheromatous plaque (plaque is released from vessels in blood and depositing in toes.)

Typically occurs within 3-10 weeks of warfarin initiation

Front 95

Warfarin Drug Interactions that increase INR.

Back 95

Amiodarone (potassium channel blocker/ Class III)
EtOH (acute*)
ASA (aspiriin)
NSAID’s (Ibuprofen, naproxen, etc.)
Celecoxib (Celebrex) anti inflammatory
Most antibiotics (Bactrim, Flagyl, Cephalosporins, Fluoroquinolones, Erythromycin, Tetracycline, etc.)
Fluconazole (Diflucan)
Garlic, gingko, ginseng, green tea

Front 96

Warfarin drug interactions that decrease INR.

Back 96

EtOH (chronic)
Barbiturates/ Phenobarbital (enzyme inducers; rapid metabolism; eliminated quicker and less efficacy)
Carbamazepine (Tegretol)
Phenytoin (enzyme inducer)
Vitamin K

Front 97

Warfarin drug interactions that impair absorption.

Back 97

Bile acid sequestrants (hyperlipidemias)—Questran ; local and bind to GI tract interfering with absorption.