Thromboembolism heparin therapy

The convenience (and cost-effectiveness) of LMW heparin therapy has resulted in widespread changes in practice. Patients with acute venous thromboembolism can be treated safely and effectively with LMW heparin as outpatients. Large-scale studies have demonstrated that outpatient treatment of acute deep vein thrombosis (DVT) with unmonitored body-weight adjusted LMW heparin is as safe and effective as inpatient treatment with adjusted dose intravenous standard heparin. Further trials have confirmed the safety and efficacy of LMW heparin therapy in acute pulmonary embolism and that 80% of imselected patients with acute thromboembolism can be safely treated as outpatients. ... 

ADMINISTRATION AND MONITORING FuU-dose heparin therapy usually is administered by continuous intravenous infusion. Treatment of venous thromboembolism is initiated with a bolus injection of 5000 units, followed by 1200-1600 units/h delivered by an infusion pump. Therapy routinely is monitored by the aPTT the target is an elevation to 1.8-2.5 times the normal value. The risk of recurrence of thromboembolism is greater in patients who do not achieve a therapeutic level of anticoagulation within the first 24 hours. Initially, the aPTT should be measured and the infusion rate adjusted every 6 hours dose adjustments may be aided by use of a nomogram. Once a steady dosage schedule has been established, daily monitoring is sufficient. 

Low-dose heparin therapy is used prophylacticaUy to prevent deep venous thrombosis and thromboembolism in susceptible patients, to whom it should be administered every 8 hours in a hospital setting laboratory monitoring is unnecessary in this setting. 

Patients with cancer who develop a venous thromboembolism may benefit from long-term therapy with a low molecular weight heparin (at least the first 3-6 mo of pharmacotherapy) instead of oral warfarin... 

J Heparin-induced thrombocytopenia (HIT) is a serious immune-mediated problem that requires immediate intervention. For patients receiving therapeutic UFH doses, a baseline platelet count should be obtained before therapy is initiated and then every-other-day for 14 days or until therapy is stopped, whichever occurs first. HIT should be suspected if a patient develops a thromboembolic event (e.g., DVT, PE, stroke, myocardial infarction, limb artery occlusion) during or soon after receiving UFH. The platelet... 

White clot syndrome - Rarely, patients may develop new thrombus formation in association with thrombocytopenia resulting from irreversible aggregation of platelets induced by heparin, the so-called white clot syndrome. The process may lead to severe thromboembolic complications. Monitor platelet counts before and during therapy. If significant thrombocytopenia occurs, immediately... 

Carter BL. Therapy of acute thromboembolism with heparin and warfarin. Clin Pharm 1991 10 503-18. 

Many women with pregnancy-inflnenced gastrointestinal issues can be treated safely with lifestyle modification or medications, many of them nonprescription. Gestational diabetes, hypertension, and thyrotoxicosis may or may not require drug therapy venous thromboembolism usually will require therapy with a low-molecular-weight heparin and compression stockings. 

Dalteparin is a low-molecular-weight heparin that inhibits reactions that lead to clotting. Dalteparin sodium is indicated in the prophylaxis of deep vein thrombosis (DVT), which may lead to pulmonary embohsm in patients undergoing hip replacement surgery or in patients undergoing abdominal surgery who are at risk for thromboembolic complications and prophylaxis of ischemic comphcations in unstable angina and non-Q-wave myocardial infarction (MI) in patients on aspirin therapy. 

Heparin-induced thrombocytopenia (platelet count <150,000/ml or a 50% decrease from the pretreatment value) occurs in about 0.5% of medical patients 5 to 10 days after initiation of therapy with standard heparin. The incidence of thrombocytopenia is lower with low-molecular-weight heparin. Thrombotic complications that can be life threatening or lead to amputation occur in about one-half of the affected heparin-treated patients and may precede the onset of thrombocytopenia. The incidence of heparin-induced thrombocytopenia and thrombosis is higher in surgical patients. Venous thromboembolism occurs most commonly, but arterial thromboses causing limb ischemia, myocardial infarction, and stroke also occur. Bilateral adrenal hemorrhage, skin lesions at the site of subcutaneous heparin injection, and a variety of systemic reactions may accompany heparin-induced thrombocytopenia. The development of IgG antibodies against complexes of heparin with... 

Low-Molecular-Weight Heparins in Prophylaxis and Therapy of Thromboembolic Diseases, edited by Henri Bounameaux... 

The comprehensive review by Douglas provides a recent discussion of the clinically useful anticoagulants. Recent studies have shown heparin to be clearly effective in clinical states In which disseminated Intravascular coagulation was Indicated to be a pathologic factor.75 xhe most commonly employed oral anticoagulants are of the coumarin type such as warfarin and nicoumalone. The oral anticoagulants appear to be of value in the prevention of thromboembolic complications after myocardial infarction.9 76 However, anticoagulation therapy has been found to have no effect on death-rate in these patients.77 Warfarin has been shown to be effective in the prevention of postoperative venous thrombosis. 

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