Preventive Therapy

Nonpharmacologic

Ambulation

A key preventive measure is for patients to become ambulatory as soon as possible. Venous stasis is due primarily to immobility.

Leg elevation

Elevate heels above the heart to increase venous return.

Elastic compression stockings

Decreases venous stasis by applying the greatest compression at the ankle and gradually decreasing compression as the stocking approaches the thigh.

Pharmacologic

Once a stroke patient’s condition has been evaluated, drug therapy becomes a very important issue. In order to reduce the development of more thrombi, patients are usually started on Heparin. Heparin, an agent used for the prophylaxis and treatment of thromboembolic disorders, works by catalyzing the action of antithrombin III inactivating thrombin and preventing the conversion of fibrinogen to fibrin. Heparin can be administered as an intermittent dose of 5000 units SC every 8-12 hours or continuous infusion calculated by a weight-based protocol.

The use of heparin, especially subcutaneously, has been effective in prophylaxis therapy against thromboembolisms; however, it is not economical to keep the patient in the hospital for long periods of time to prophylaxis with heparin. The development of Low Molecular Weight Heparins (LMWHs) has enabled the stroke patient to decrease their hospital stay but still get the proper treatment to avoid venous thromboembolisms.

Low Molecular Weight Heparins (LMWHs)

  • Use:
    Prophylaxis of thromboembolic disorders (DVT with or without pulmonary embolism)
  • MOA:
    Fractions of heparin with a small effect on the apt (less binding with thrombin) and strongly inhibits factor Xa; Higher ratio of antifactor Xa to antifactor IIa activity then unfractionated heparin
  • Kinetics:
    Onset of action — occurs 3-5 hours after subcutaneous administration
    Duration — persists in plasma ~ 12 hours
    Half-life—2-4 times that of Heparin (1.5hrs)
    No hepatic metabolism; slow,steady renal elimination
  • Adverse Reactions:
    Bleeding, erythema, thrombocytopenia, urticaria
  • Monitoring:
    Platelets, occult blood
  • Drug Interactions:
    Drugs affecting platelet function may potentiate risk of hemorrhage (warfarin, aspirin, NSAIDs, dipyridamole, ticlopidine)
  • Dosing:
    Each LMWH has its own dosing values
  • Products:

    ENOXOPARIN
    Concurrent treatment with oral anticoagulation for treatment of DVT; Secondary prevention of DVT with or without PE in inpatients or for treatment in selected outpatients for acute DVT without PE

    Prophylactic Dosing:

    30mg SC Bid

    Duration:

    Twice daily until threat of DVTs has diminished. Average length of therapy is 7-10 days.

    Treatment Dosing:

    1mg/kg/dose SC Bid

    Duration:

    Within 72 hours of initiation with enoxaparin, warfarin therapy is started. Concurrent use of warfarin and enoxaparin are continued until an adequate response from warfarin (INR 2-3) is achieved. ACCP recommends concurrent use for 4-5 days and discontinue after 7 days.

    Administration:

    Alternate injection site frequently; Hold skin fold until needle is withdrawn; Inject in left or right antero-lateral and posterolateral abdominal wall

    Adverse Reactions:

    bleeding, erythema, bruising

    Monitoring:

    platelets, occult blood

    Strengths: 10mg/0.1 ml (30, 40 60, 80, 100mg)
    DALTEPARIN
    Dosing: 100units/kg Bid or 200units/kg QD
    Administration: Alternate injection site frequently; Hold skin fold until needle is withdrawn; inject in U-shape area around navel, upper or outer area of the thigh, or upper quadrangle of the buttocks
    Strengths: 2500 units/0.2ml, 5000 units/0.2ml, 95,000 units/0.2ml