Comments on 'Thrombophylaxis: Questions & Controversies'

BY ALI ABURAHMA, M.D.

The importance of deep vein thrombosis prevention is paramount in a significant number of patients, as seen in the orthopedic patients in the National Confidential Inquiry Into Perioperative Deaths Study (NCIPOD), which indicates that pulmonary embolism was the cause of death in 35% of patients at autopsy, following hip replacement.

Graduated compression stockings and intermittent leg compression devices decrease the incidence of deep vein thrombosis in moderate-risk surgical patients. I use this routinely in surgical and trauma patients, with good reason, because approximately 50% of deep vein thrombosis cases occur intraoperatively.

Dr. William Geerts' indication that he opposes the use of mechanical prophylaxis, except when there is no alternative, is understandable since quite a few of the patients don't comply with its use, particularly those in the non-acute care setting.

With the use of low-molecular-weight heparin products, and with no need for frequent laboratory work to assess the level of anticoagulation, this anticoagulation therapy has become increasingly popular as a means of prophylaxis. Several randomized controlled trials have shown low-molecular-weight heparin to have equal or greater effectiveness and similar or less bleeding complications than traditional unfractionated heparin.

Dr. Geerts' recommendation that 5,000 units of conventional subcutaneous heparin given every 8 hours is more effective than every 12 hours is very interesting, since this has not been previously addressed.

Finally, I somewhat agree with Dr. Geerts' statement that there is absolutely no scientific evidence that prophylactic inferior vena cava filters are indicated in any patient group; however, until this has been proved by controlled studies, prophylactic IVC filters should be considered in an extremely selective group of patients who are at an extremely high risk for pulmonary embolism.