BACKGROUND Dose adjustment or laboratory monitoring of low-molecular-weight heparin (LMWH) is commonly recommended for patients with severe renal insufficiency (creatinine clearance < or =30 mL/min), but the basis for this recommendation is unclear. PURPOSE To compare levels of anti-Xa heparin and risk for major bleeding in LMWH-treated patients with a creatinine clearance of 30 mL/min or les...

Critically ill patients commonly evince thrombocytopenia, either evident on admission to the intensive care unit (ICU) or that develops during their stay. Heparin-induced thrombocytopenia (HIT) explains thrombocytopenia in only approximately 1/100 critically ill patients; also, only 1 or 2 in 10 ICU patients with a positive PF4-dependent enzyme immunoassay has “true” HIT. Thus, there is major p...

OBJECTIVE To evaluate risk factors for venous thromboembolism (VTE) despite thromboprophylaxis in major orthopedic surgery patients at a tertiary care hospital. METHODS Charts from consecutive patients who underwent total hip replacement (THR), total knee replacement (TKR), or hip fracture surgery (HFS) [hip pinning or hemiarthroplasty] from August 1, 1999, to April 30, 2000, at a large Canad...

CASE HISTORIES Case 1: Massive Baker’s cyst presenting as a deep venous thrombosis (fig 1) A 68 year old woman presented to the accident and emergency department describing a three day history of acute left calf pain and swelling associated with severe difficulty in weight bearing. She had been previously diagnosed with hypertension, peptic ulcer disease, and had had seronegative rheumatoid art...

If laboratory monitoring of low molecular weight heparin (LMWH) therapy is required the test of choice is the anti Xa activity assay. The relationship between anti Xa results obtained using different techniques is unknown. The aim of the present study was to compare anti Xa results obtained with eight different commercially available anti Xa activity assays (five chromogenic and three clotting ...

The association between cancer and venous thromboembolism (VTE) is well established. Importantly, VTE is a significant cause of mortality in cancer patients. Although long-term warfarin (Coumadin(trade mark); Bristol-Myers Squibb; New York, NY) therapy is the mainstay of treatment for cancer patients with VTE, there are many practical problems with its use in this population. In particular, ach...