Chapter 26

Chapter 26: Drugs Used to Treat Thromboembolic Disorders

• Source: Clayton’s Basic Pharmacology for Nurses, 19th edition by Michelle Willihnganz, MS, RN, CNE

Introduction

• Focus on thromboembolic disorders, their treatment, and nursing considerations.

Lesson 26.1: Overview of Thromboembolic Disorders (1 of 2)

• Risk Factors for Blood Clots: Conditions that predispose individuals to clots include:

  • Immobility and venous stasis

  • Surgeries and trauma to the lower limbs

  • Heart failure and vasospasm

  • Various cancers (e.g., lung, prostate, stomach, pancreas)

  • Pregnancy and use of oral contraceptives

• Nursing Interventions:

  • Identify conditions and implement preventive measures against clot formation.

  • Actions of drug classes:

    • Platelet inhibitors

    • Anticoagulants

    • Thrombin inhibitors

    • Fibrinolytic agents

Lesson 26.1: Overview of Thromboembolic Disorders (2 of 2)

• Monitoring Procedures:

  • Laboratory data to detect hemorrhage in patients on anticoagulants.

  • Nursing Assessments:

    • Monitoring therapeutic responses and adverse effects of anticoagulant therapy.

Thromboembolic Diseases

• Definition: Clot (thrombus) formation in a blood vessel, which can dislodge (embolism).

• Clotting Cascade Activation: Occurs due to:

  • Blood vessel injury

  • Increased blood viscosity

• The processes involve two pathways:

  • Intrinsic Clotting Pathway

  • Extrinsic Clotting Pathway

Nonpharmacologic Treatment of Thromboembolic Diseases

• Prevention Measures:

  • Help prevent clots through:

    • Leg exercises, wearing compression stockings, leg elevation, using sequential compression devices.

    • Revascularization Treatments:

      • Procedures like percutaneous coronary intervention and coronary artery bypass grafting.

Drug Therapy Goals for Thromboembolic Diseases

• Primary Objective:

  • Prevent platelet aggregation or inhibit the clotting cascade steps.

• Types of Agents:

  • Platelet inhibitors

  • Anticoagulants

  • Glycoprotein IIb/IIIa inhibitors

  • Thrombolytics

• Therapeutic Focus:

  • Prevent new clot formation or the extension of existing clots.

Audience Response Questions

• Q1: Understand when different pathways of coagulation are triggered, especially post-surgical.

Laboratory Tests for Thromboembolic Diseases

• Coagulation Tests:

  • PT (Prothrombin Time)

  • aPTT (Activated Partial Thromboplastin Time)

  • INR (International Normalized Ratio)

  • Diagnostic Tests Include:

    • Hematocrit, platelet counts, Doppler studies, etc.

Nursing Implications and Assessments

• Assessment Considerations:

  • Patient history and current symptoms examination.

  • Vital signs, mental status, hydration state, and specific perfusion signs.

Patient Education for Anticoagulation Therapy

• Diet Recommendations:

  • Limit leafy green vegetables; maintain hydration.

  • Exercise Guidance: Post-surgery mobility to prevent venous stasis.

  • Medication Awareness:

    • Importance of a medical alert bracelet, understanding dosage, adverse effects, and drug interactions.

Drug Class: Platelet Inhibitors (1 of 2)

• Aspirin:

  • NSAID that inhibits platelet aggregation.

  • Uses:

    • Reduces MI risk in men and stroke in women; useful in acute MI.

Drug Class: Platelet Inhibitors (2 of 2)

• Clopidogrel:

  • Inhibits platelet aggregation for primary prevention of MIs and strokes.

  • Adverse Effects Include:

    • Abdominal distress, hypotension, serious bleeding complications.

Drug Class: Factor Xa Inhibitors

• Medications:

  • Apixaban, rivaroxaban, edoxaban reduce stroke and systemic embolism risk in atrial fibrillation.

  • Betrixaban for DVT/PE prophylaxis in hospitalized patients.

• Common Adverse Effect:

  • Bleeding.

Drug Class: Anticoagulants (1 of 3)

• Low-Molecular-Weight Heparin (LMWH):

  • Used to prevent DVT and MIs, especially post-surgery.

  • Adverse Effects: Hematoma, bleeding at injection site.

Enoxaparin Administration Technique

• Subcutaneous injections into abdominal areas; important technique details for efficacy and comfort.

Drug Class: Anticoagulants (2 of 3)

• Heparin:

  • Neutralizes thrombin and various clotting factors.

  • Administration routes and monitoring requirements discussed.

Heparin Administration (1 of 2)

• Best practices in calculating dosing and subcutaneous injection protocols.

Heparin Administration (2 of 2)

• Potential adverse effects and serious complications including various forms of bleeding.

Drug Class: Anticoagulants (3 of 3)

• Warfarin (Coumadin):

  • Vitamin K antagonist impacting clotting factors.

  • Target INR ranges requisite for patients based on clinical factors.

Warfarin Adverse Effects

• Anticipated bleeding risks and considerations in patient education.

Coumadin: Premedication Assessment

• Necessary assessments before administering Warfarin, including PT/INR history and dietary education.

Correct Dosing

• Importance of accurate medication administration and checking laboratory results prior to anticoagulant administration.

Audience Response Questions

• Various scenarios about anticoagulant treatment emphasize the practical management of patients on anticoagulants, enhancing understanding for correct application in clinical settings.