- Low molecular weight, cationic, strongly basic protein - from Salmon sperm - Heparin antagonist

- Dalteparin - Enoxaparin - Tinzaparin

Class 8 Deck 1 Flashcards by Charles Grant

Heparin is an ________, ___________ glycosoaminoglycan found in the secretory granules of __________.

Anionic (charged)
Sulfated
Mast Cells

How well did you know this?

Not at all

Perfectly

How does heparin work?

accelerate rate which ATIII neutralizes thrombin (IIa) and factor Xa
Prevents fibrinogen from converting to fibrin

How well did you know this?

Not at all

Perfectly

When is heparin used?

Phophylaxis treatment of Embolisms
DIC
Anticoag during cardiac surgery
Management of angina, MI, PCI
Pregnancy complications

How well did you know this?

Not at all

Perfectly

Heparin can only work on what type of factors?

-Unbound (not attached to platelet)

How well did you know this?

Not at all

Perfectly

Heparin is cleared by what?

-Reticuloendothelial system

How well did you know this?

Not at all

Perfectly

Does heparin cross the placenta? Warfarin?

Heparin does not cross placenta

- Warfarin does cross the placenta

How well did you know this?

Not at all

Perfectly

What can cause heparin resistance?

Increased factor VIII
Accelerated clearance w/ massive PE
Inherited ATIII deficiency
Acquired ATIII deficiency

How well did you know this?

Not at all

Perfectly

What causes acquired ATIII deficiency? and how to treat?

Cirrhosis, Nephrotic syndrome, DIC

- FFP or ATIII concentrate

How well did you know this?

Not at all

Perfectly

What are some problems associated with heparin toxicity?

Bleeding
Thrombocytopenia (HIT)
Abnormal LFTs
Osteoperosis / vertebral fractures

How well did you know this?

Not at all

Perfectly

What is protamine?

Low molecular weight, cationic, strongly basic protein
from Salmon sperm
Heparin antagonist

How well did you know this?

Not at all

Perfectly

Protamine has what effect on LMWHs?

-Not as effective, only 65% neutralization

How well did you know this?

Not at all

Perfectly

What are the doses of protamine?

1-1.5mg per 100 units of heparin
0.5-0.75 after 30-60 minutes
0.25-0.375 after 2 hours

How well did you know this?

Not at all

Perfectly

What are the adverse effects of protamine?

Histamine hypotension
Brady
Pulmonary HTN
Flushing
Dyspnea

How well did you know this?

Not at all

Perfectly

What are the hypersenitivity reactions of protamine?

Uticaria
Angioedema
Pulmonary HTN
Anaphylactoid/Anaphylaxis

How well did you know this?

Not at all

Perfectly

What groups of people are at risk for hypersensitivity to proatmine?

Fish allergy
Previous protamine reversal
Protamine containing insulin (NPH)
Previous vasectomy

How well did you know this?

Not at all

Perfectly

How do you pretreat for protamine hypersensitivity?

Corticosteroids

- Antihistamine

How well did you know this?

Not at all

Perfectly

What is heparin rebound?

Re-anitcoagulate after protamine reversal

- Usually 8-9 hours (reported 30min to 18hrs post CPB)

How well did you know this?

Not at all

Perfectly

What can happen with protamine OD?

Bleeding

- Has anticoags and antiplatelets when given alone or in excess of heparin

How well did you know this?

Not at all

Perfectly

Name 3 LMWH

Dalteparin
Enoxaparin
Tinzaparin

How do LMWH work?

-Inhibition of factor Xa by antithrombin

What are the advantages of LMWH?

Fixed dose sub Q

- Not dose monitoring or adjustments

What are LMWH uses

Post op DVT/Embolisms

- Angina, MI, AFib

Can dosages of LMWH and Heparin be used interchangeably?

What are the adverese effects of LMWH?

Thrombocytopenia
Do not use with HIT
Decrease dose in renal patients

What does Fondaparinux (Arixtra®) do?

- Synthetic inhibitor of factor Xa - ATIII mediated - No effect on IIa or platelets

Advantages of Fondaparinux (Arixtra®)?

- Fixed dose / Once daily - No monitoring or dose adjustments - No HIT (stop use if platelets fall below 100,000)

When is Fondaparinux (Arixtra®) used?

-Prevention / treatment of DVT/Embolism

What 2 anticoags can cause spinal or epidual hematomas?

- LMWH | - Fondaparinux (Arixtra®)

What kind of drug is Danaproid Sodium (Orgaran ®)?

Heparinoid - anti-factor Xa - Contains no Heparin

What is Argatroban (formerly Acova®) and what does it do?

- Direct / reversible thrombin inhibitor | - Works on bound and unbound thrombin

Argatroban (formerly Acova®) is used for what?

-Thrombus in patients w/ HIT or HITTS (those that can't use heparin)

Name 2 Hirundin Analogs (leech saliva)

Bivalirudin (Angiomax ®) | Lepirudin (Refludin®)

How does Lepirudin (Refludin®) work?

- direct thrombin inhibitor | - Binds irreversibly to bound and unbound thrombin (IIa)

When is Lepirudin (Refludin®) used and how is it excreted?

- thrombosis associated with HIT | - Kidneys

How does Warfarin work?

- indirect anticoagulant | - Alters factors II, VII, IX, and X by interfering with vitamin K.

What is the treatment for warfarin bleeding?

- Vitamin K (Takes 24hrs) | - FFP (immediate)

Warfarin is what kind of pregnancy drug?

Category X

Warfarin interacts with what other drugs?

- ABX - Acetaminophen - Antiepiletics - Blood thinners - NSADIS - Supplements

Name 3 Novel Oral Anticoags

Dabigatran (Pradaxa®): Oral direct thrombin inhibitor Apixaban (Eliquis®): Oral direct Factor Xa inhibitor Rivaroxaban (Xarelto®): Oral factor Xa inhibitor

Dabigatran (Pradaxa®) is eliminated how?

- 80% by kidneys | - Dose adjustments needed for CKD

Dabigatran (Pradaxa®) should be held for how long prior to surgery?

- CrCl >50 1-2 days | - CrCl < 50 3-5 days

ApiXaban (Eliquis®) is used when?

- Reduce stroke and embolization in patients w/ non-valvular AFib - DVT after total hip

RivaroXaban (Xarelto®) is used when?

- Reduce stroke and embolization in patients w/ non-valvular AFib - DVT after total hip / Knee

Should be used with caution in what type of patients?

-Renal failure

Apixaban should be used with caution in what type of patients?

-Liver failure

Novel Oral Antigcoags should not be used with what other drugs?

- Strong inhibitors/inducers of CYP3A4 or P-Glycoproteins - NSAIDS - Anitplatlet