1. Drugs for Coagulation Disorders20
Drugs for Coagulation Disorders

2. Learning Outcomes Explain the importance of hemostasis.
Construct a flow chart diagramming the important steps of hemostasis and fibrinolysis.
Describe the types of disorders for which coagulation modifier drugs are prescribed.
Identify the primary mechanisms by which coagulation modifier drugs act.

3. Learning Outcomes
For each of the classes in the Drug Snapshot, identify representative drugs, explain their mechanisms of action, primary actions, and important adverse effects.
Categorize coagulation modifier drugs based on their classifications and mechanisms of action.

4. Core Concept 20.1
Hemostasis is a complex process involving multiple steps and many clotting factors. Hemostasis is the balance between clot formation and clot breakdown

5. Coagulation
Everyone is familiar with simple cuts and scraps and we all take for granted that they will stop bleeding in a few minutes.

6. Basic steps in hemostasis

7. Major steps in the coagulation cascade

8. Coagulation Cascade This process normally takes about 6 minutes
Vitamin K is required for the liver to produce these clotting factors
Liver disease can greatly effect coagulation

9. Removing a blood clot is essential to restoring normal circulation.
Core Concept 20.2
Removing a blood clot is essential to restoring normal circulation.

10. Primary steps in fibrinolysis

11. Fibrinolysis

12. Clots
Once a stationary clot forms (thrombus), it often grows larger as more fibrin is added.
Pieces of the clot may break off and travel in the blood stream to possibly lodge elsewhere.
A traveling clot is know as an embolus
When clots or emboli form, drug therapy becomes necessary.

13. Deep Vein Thrombosis/Embolus

14. Drugs are used to modify the coagulation process.
Core Concept 20.3
Drugs are used to modify the coagulation process.

15. Drugs Anticoagulants used to prevent the formation of clots
Inhibit specific clotting factors in the coagulation cascade or diminish the clotting action of platelets
Increase the normal time the body takes to form clots

16. “Blood Thinners” This is an incorrect term;
However, it is commonly used.
The drugs do not change the thickness of the blood, just inhibits the clotting cascade

17. Drugs Thrombolytics used to dissolve such life-threatening clots.
Hemostatics used to speed clot formation, or to limit bleeding from a surgical site.

18. Anticoagulants prevent the formation and enlargement of clots.
Core Concept 20.4
Anticoagulants prevent the formation and enlargement of clots.

19. Anticoagulants Actions Adverse effect is bleeding.
Inhibit certain clotting factors
Lengthen clotting time
Prevent thrombi from forming or growing larger
Adverse effect is bleeding.
Specific blockers administered to reverse the anticoagulant effects

20. Primary Anticoagulants
heparin (Hep-Lock
warfarin (Coumadin)
Coumadin therapy can overlap heparin therapy
Do not give ASA with these drugs
RANDI Precautions

22. Antidotes: Anticoagulants Protamine sulfate is used for heparin
Vitamin K is administered for warfarin.

23. Vitamin K
Foods high in Vitamin K can reverse the action of warfarin (Coumadin)
Green leafy vegetables
Milk and milk products
Some cereals
Orange juice
Cauliflower
Cucumbers

24. Laboratory Tests Oral Anticoagulants
Prothrombin time (PT)
Normal range for PT is 12 to 15 seconds
Prolonged with anticoagulant treatment.
International Normalized Ratio (INR)
Method of performing PT tests varies from laboratory to laboratory

25. Laboratory Tests Oral Anticoagulants
This is PT multiplied by a correction factor.
Recommended post-treatment INR values range from 2 to 4.5.

26. Mechanism of action of anticoagulants

28. Adverse Effects
Most common and potentially serious adverse effect is bleeding.
Signs:
Bruising
Bleeding gums
Nosebleed
Blood in urine or stool

29. Signs of Bleeding

30. Core Concept 20.5
Antiplatelet agents prolong bleeding time by interfering with platelet aggregation.

31. Antiplatelet Agents Used to prevent clot formation in arteries.
Three primary subclasses of antiplatelet agents
Aspirin
Adenosine diphosphate (ADP) receptor blockers
Glycoprotein IIb/IIIa receptor blockers.

33. Thrombolytics are used to dissolve existing clots.
Core Concept 20.6
Thrombolytics are used to dissolve existing clots.

34. Thrombolytics
Prescribed for disorders in which a clot has already formed, including the following:
Acute MI
Pulmonary embolism
Cerebrovascular accident (CVA)
DVT

35. Thrombolytics
Prescribed for disorders in which a clot has already formed, including the following:
Arterial thrombosis
Coronary thrombosis
To clear thrombi in arteriovenous cannulas and blocked IV catheters

37. Hemostatics are used to promote the formation of clots.
Core Concept 20.7
Hemostatics are used to promote the formation of clots.