Warfarin pulmonary embolism

Warfarin is used as an anticoagulant for preventing and treating deep venous thromboses and pulmonary embolism. Synonyms of this drug are cumadin, panwarfm, sofrain, wamerin, and others. 

In present times, because of early mobilization and shorter stays in hospital, venous thrombosis in the legs and resulting pulmonary embolism has declined to a large degree. In persons with acute myocardial infarction, prophylactic low-dose heparin has reduced the incidence of venous thrombosis in the legs. It is considered as a reasonable alternative to warfarin in selected patients. Preventive anlicoagulalion may be indicated in some cases to prevent strokes due to left ventricular mitral thrombi embolizing in tire brain. 

Problem/lnfluence of Medication. St. John s wort can cause enzyme induction, which results in an increase in the liver s ability to metabolize other medications, including warfarin. This process could result in the warfarin being metabolized too rapidly and therefore failing to reach therapeutic levels. Lack of adequate anticoagulant effects would place the patient at increased risk for subsequent thrombosis and pulmonary embolism. 

When these patients are discharged from hospital, prophylactic treatment with an oral anticoagulant is recommended to prevent recurrence of the thrombosis. Warfarin sodium, which antagonizes the effects of vitamin K, is used in prophylaxis and treatment of DVT and pulmonary embolism. It is usual to start with an induction dose of 10 mg daily for two days the dose can then be reduced. Patients need to be monitored as there is a risk of haemorrhage with oral anticoagulant drugs. 

Fondaparinux is a selective inhibitor factor Xa possessing a selective inhibition of antithrombin III (ATIII), which potentiates the innate neutralization of factor Xa by ATIII. Nentralization of factor Xa interrupts the blood coagulation cascade and inhibits thrombin formation and thrombus development. It is indicated for prophylaxis of deep vein thrombosis (DVT) that may lead to pulmonary embolism in patients undergoing hip fracture surgery including extended prophylaxis, hip replacement surgery, or knee replacement surgery. When administered in conjunction with warfarin, fondaparinux is indicated for treatment of acute DVT and acute pulmonary embolism. 

Tinzaparin sodium is a low-molecular-weight heparin that inhibits reactions leading to the clotting of blood, including the formation of fibrin clots. It is indicated in the treatment of acute symptomatic deep vein thrombosis with or without pulmonary embolism when administered with warfarin. 

Warfarin (Coumadin) Antagonize vitamin K. Interfere with the synthesis of vitamin K-dependent clotting factors (II, VII, IX, X). Deep venous thrombosis, ischemic heart disease (selected patients), rheumatic heart disease, pulmonary embolism. Lifelong use in patients with artificial heart valves. Bleeding, hemorrhage, necrosis, Gl upset. 

A 39-year-old woman with familial type 1 antithrombin deficiency and a history of extensive deep vein thrombosis and pulmonary embolism, taking warfarin, was given levonorgestrel for emergency contraception. 

Etretinate. A man with T-cell lymphoma who had recently been given chemotherapy (cyclophosphamide, doxorubicin, vincristine and prednisolone) was anticoagulated with warfarin after developing a pulmonary embolism. About three weeks later, he started etretinate 40 mg daily and it was found necessary to increase his warfarin dosage from 7 to 10 mg daily. His liver function tests were normal. This patient had also recently started taking co-proxamol , (p.436), tolbutamide , (p.380) and cimeti-dine , (p.412) , but all of these have been reported to only rarely increase the effect of warfarin. 

A phase II study to investigate the efficacy and tolerability of the concurrent use of thalidomide 100 mg daily and darbepoetin-alfa 2.25 micrograms/kg per week subcutaneously in patients with myeiodysplastic syndrome was discontinued because of an unexpectedly high incidence of thromboembolic events. Of the first 7 patients enrolled in the study, two developed deep vein thrombosis and one died of pulmonary embolism. The authors recommended careful monitoring and possibly thromboprophylaxis (heparin or warfarin) in patients with myeiodysplastic syndrome given both thalidomide and epoetin. ... 

Warfarin is the most commonly prescribed oral anticoagulant, with four million U.S. patients taking the drug for treatment and prevention of atrial fibrillation, stroke, deep vein thrombosis, or pulmonary embolism, and for those who have had heart valve replacement surgery. Adverse reactions to warfarin... 

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