April 1st 2007abstract: Low molecular weight heparins (LMWHs) have proved to be as safe and effective as unfractionated heparin for the treatment of venous thromboembolism. They have the advantage of not requiring frequent measurement of activated partial thromboplastin time and subsequent dosage adjustments. Patients who have deep venous thrombosis can be treated with once- or twice-daily subcutaneous doses. Hospital admission is necessary for patients with risk factors for major bleeding complications, for those with symptomatic pulmonary embolism, or when noncompliance is likely. Symptomatic proximal deep venous thrombosis and asymptomatic pulmonary embolism may be managed on an outpatient basis if there are no contraindications. Although heparin-induced thrombocytopenia occurs less frequently with LMWHs than with unfractionated heparin, the platelet count must still be monitored during therapy. (J Respir Dis. 2007;28(4):132-138)