Cardioiap.org

Q& A on anticoagulants and warfarin
What are the anticoagulants? When are they required in Children?
Anticoagulants interfere with the process of clot formation by inhibiting vitamin K. Sometimes, children have more than normal capacity to form clots inside the heart or circulatory system and may suffer due to that. Any such condition would require the anticoagulant to maintain normal blood flow.
What are those conditions where anticoagulants are required?
In children with abnormal heart function and those who have received some foreign material like valves or conduits the process of clot formation is augmented. Besides, few kids are born with the disorders like protein S or C deficiency, are also candidates for the anticoagulation. What are the regularly used anticoagulants?
The Heparin is the one of most frequently used injectable anticoagulant. Now a day’s low molecular weight heparin is being used exceedingly. The vitamin K antagonists like warfare (Dicoumarol) and acitrom (Nicoumalone) are the oral agent. What is the difference between thrombolytic therapy and anticoagulation?
Anticoagulants are basical y used for prevention of clot formation. Though, they also help in thrombolysis as they prevent progression of thrombus to let natural process of clot removal take place. Thrombolytic agents are the drugs that can dissolve a clot. Currently available thrombolytic agents include reteplase (r-PA or Retavase), alteplase (t-PA or Activase), urokinase (Abbokinase), prourokinase, anisoylated purified streptokinase activator complex (APSAC), and streptokinase.
What are the newer Anticoagulant?
Basical y clot prevention therapy can act at three levels - 1. Vitamin K 2. thrombin inhibitor, 3. factor Xa inhibitors. Old anticoagulants were vitamin K inhibitors. New anticoagulants target a single coagulation factor and have predictable dose-response relationships.
Like direct thrombin inhibitor lepirudin and argatroban, Bivalirudin and ximelagatran (prodrug- melagatran) or factor Xa inhibitors like Fondaparinux are in use.
What does warfarin do ?
Warfarin increase the time taken for the clot formation. How much time it takes to start action ?
Depending on starting dose it takes 3 to 5 days to act. Hence in emergent situation the warfarin therapy can be overlapped by heparin.
How the warfarin is used?
Warfarin comes in tablet to take by mouth. It is taken daily as a single dose at the same time.
What is the INR monitoring?
INR (international normalized ratio) is the standardized value of thrombin activity after the warfarin treatment. The dose is adjusted according to regular blood tests – INR monitoring. Usual range for INR is between 2-3 for most of conditions. (see chart) What are the special precautions for warfarin therapy?
There are many things about which one must be careful . Dosing must be exact and at the same time and under the doctor’s prescription. No other medications , prescribed or un-prescribed must be taken without doctor’s knowledge. No herbal medications must be taken without permission of the doctor.
What are dietary restriction with warfarin?
Mostly green leafy vegetables and many other food materials are rich in vitamin K. Hence they counteract the action of warfarin. Hence, a fixed instead of restricted diet is recommended and accordingly warfarin doses are regulated. If one changes the dietary content abruptly the level of warfarin may be affected.
What are the side effects of warfarin?
Stomach problem, hair loss, change in appetite, al ergy, bleeding are the side effects.
What are the alarming side effects of warfarin?
If one is having it itching , rash, chest compression, tingling, diarrhea flue like symptoms or constant bleeding, jaundice, muscle pain must inform to the doctor.
Can warfarin cause skin necrosis or gangrene?
If one notices darkening of skin or purple discoloration , ulcerations should get back to doctor! How can we can monitor and regulate doses of warfarin sodium?
Stop warfarin. Contact patient for examination.
Stop warfarin for 2 days; decrease weekly dosage by 25% or by 1 mg/d for next week (7 mg Decrease weekly dosage by 15% or by 1 mg/d for 5 days of next week (5 mg total); repeat Decrease weekly dosage by 10% or by 1 mg/d for 3 days of next week (3 mg total); repeat Increase iIncrease the Weekly dosage by 10% or by 1 mg/d for 3 days of next week (3 mg total); Increase I Increase Weekly dose by 15% or by 1 mg/d for 5 days of next week (5 mg total); repeat PT in

Source: http://www.cardioiap.org/PDF/aniticogulant.pdf