Resident & Staff Physician®, January 2008 Vol 54 No 1, Volume 0, Issue 0
Prepared by Tarek Darwish, MD, Assistant Professor of Medicine, Department of InternalMedicine, Division of Hospital Medicine, University of Missouri-Kansas City
Assess patients on admission and on a daily basis for possible change of deep-vein thrombosis (DVT) status, including the total risk factor score (a score of 2 or above is an indication for prophylaxis). In some cases, pharmacologic prophylaxis may need to be continued posthospitalization.
Don?t forget to ask about a history of DVT or pulmonary embolism, and make DVT prophylaxis an essential part of your assessment and management plan.
Mechanical prophylaxis, such as a sequential compression device or graduated compression stockings, should be considered in patients with contraindications to anticoagulation (eg, active hemorrhage, recent intraocular or intracranial surgery, heparin-induced thrombocytopenia [HIT], spinal tap or epidural anesthesia within 24 hours).
Unfractionated heparin and low-molecularweight heparin (LMWH) are the most common pharmacologic agents used in hospitalized patients. No single agent has been proved superior to another in efficacy; however, unfractionated heparin, given 3 times daily, is associated with a greater incidence of HIT and requires more nursing time.
Remember to use unfractionated heparin 3 times daily instead of twice daily in medical and surgical patients because of the lack of convincing evidence showing efficacy of twice-daily unfractionated heparin.
The combination of pharmacologic and mechanical prophylaxis is recommended in very-high-risk patients, despite the absence of randomized controlled trials.
Remember to withhold unfractionated heparin 4 to 6 hours and LMWH 24 hours before placement or removal of an epidural or spinal catheter.
LMWH may be preferred to unfractionated heparin in patients with malignancy based on the recent findings of antineoplastic and antiangiogenic effects of LMWH.
Consider checking the patient?s complete blood count, with differential, periodically in those receiving unfractionated heparin or LMWH therapy; recognize HIT early as the most common serious drug reaction in the hospital setting.
Use LMWH with caution in patients with renal failure (eg, serum creatinine clearance under 30 mL/min).