ANTICOAGULANTS THROMBOLYTICS

DEFINITIONS

w    Antiplatelets

•    Inhibits platelets from adhering to fibrin lattice

•    Use:  TIA, cardiac prosthetic valve, post MI

w    Anticoagulants

•    Prevents coagulation cascade

•    Prevents progression of clot

•    Allow internal plasmin to dissolve clot

DEFINITIONS

w    THROMBOLYTIC

•    Dissolves Clot

COAGULATION CASCADE

w    Clotting factors activated

w    Prothrombin  converted to thrombin

•    Blocked by Antithrombin III

w    Fibrinogen converted to fibrin

w    Fibrin forms a lattice

w    Platelets bind to the lattice

Heparin

w    Activates Antithrombin III

w    Injectable administration only

•    Subcutaneous - prevent post operative clotting, or bed ridden patient clotting

•    Heparin flush

•    Constant infusion following bolus dose

•   Treatment of deep venous thrombosis, pulmonary embolism

•   Eventually may switch to warfarin

HEPARIN MONITORING

w    Activated Partial Thromoboplastin Time

•    1 1/2 to 2 1/2 times control

w    Bleeding

w    No intramuscular injections

LOW MOLECULAR WEIGHT HEPARINS

w    Less bleeding reactions

w    Subcutaneous administration

w    Can be utilized for ambulatory care therapy

w    Example:

•    Enoxaparin (Lovenox®)

•    Dalteparin (Fragmin®)

HEPARIN ANTIDOTE

w    Protamine Sulfate

•    Binds excess heparin

•    1mg binds 100 units of heparin

•    Excess protamine has anticoagulant properties

WARFARIN

w    Decreases production of vitamin K dependent clotting factors in the liver

w    High protein binding - leads to many drug interactions

w    Monitor Prothrombin Time

•    INR 2 to 3

w    Effect of each dose is not seen for 3 days

w    Maintain consistent vitamin K diet

WARFARIN USE

w    Continuation therapy of heparin therapy for approximately 6 months

•    Deep Venous Thrombosis

•    Pulmonary Embolism

w    Cardiac Valve Replacement, Atrial fibrillation - life long therapy

w    CONTRAINDICATION - pregnancy

WARFARIN OVERDOSE ANTIDOTE

w    Phytonadione (Vitamin K)

w    Administer via subcutaneous route

THROMBOLYTIC AGENTS

w     DIRECT ACTING

 

•     Urokinase

•     Alteplase

 

w     INDIRECT ACTING

 

•     Streptokinase

DIRECT ACTING

 

w    Urokinase -Utilized to open clotted catheters

w    Alteplase - Use

•    Pulmonary Embolism

•    Myocardial Infarction

•    Stroke (clot)

 

 

INDIRECT ACTING

w    Stimulates conversion of plaminogen to plasmin

w    Streptokinase – Use

•    Pulmonary Embolism