Anticoagulants

Mechanism of Action

• Exert action in the clotting cascade
• Therapeutic Effects:
  • Prevent clot formation (antithrombotic)
  • Used to prevent thrombus formation

Indications

• Coronary artery disease
• Heart failure
• Heart valve replacement
• History of thrombotic strokes (ischemic strokes)
• Deep Vein Thrombosis (DVT)
• Pulmonary embolism

Precautions & Contraindications

• Precautions:
  • Blood dyscrasia (clotting disorders like hemophilia)
  • Recent surgery
  • Concurrent use of other drugs affecting clotting
• Contraindications:
  • Pregnancy (depends on the agent)
  • Active bleeding (visible and occult)

Side Effects

• Bleeding
• Nausea, vomiting
• Hypotension (in high doses)
• Cardiac dysrhythmias
• Thrombocytopenia (low platelets)
• Heparin-induced thrombocytopenia (HIT)

Nursing Actions

• Assess for active bleeding (visible and occult)
• Monitor appropriate drug dosing
• Follow lab results (CBC, hemoglobin, hematocrit, platelets)
• Educate patient on treatment, dosing, labs, and safety

Examples of Drugs

Warfarin

• Type: Coumadin derivative
• Action: Inhibits vitamin K synthesis
  • Reduces vitamin K dependent clotting factors
• Route: Oral
• Dietary Considerations: Avoid green leafy vegetables (rich in vitamin K)
• Dosage Adjustment: Based on INR and PT
  • INR (International Normalized Ratio): Normal = 1; Therapeutic = 2 to 3.5
  • PT (Prothrombin Time): Assessed alongside INR
• Reversal Agent: Vitamin K

Heparin

• Type: Anticoagulant
• Routes: IV and subcutaneous
• Dosage Monitoring: Based on PTT (Partial Thromboplastin Time)
  • PTT: Used to assess therapeutic effectiveness
• Reversal Agent: Protamine sulfate

Lovenox (Enoxaparin)

• Type: Low molecular weight heparin (LMWH)
• Use: Prophylaxis to prevent DVTs
• Reversal Agent: Protamine sulfate

Other Antithrombotics

• Apixaban (Eliquis)
• Rivaroxaban (Xarelto)
• Dabigatran (Pradaxa)
• Commonly used in acute care settings