September 12, 2012

Are Anticoagulants Overused Because
of Too-Sensitive Blood Clot Screening?

Boston—Standard operating procedure at most hospitals is to administer anticoagulants to joint replacement patients or those with serious fractures to prevent pulmonary emboli (PE). A new review article suggests, however, that some of the blood clots picked up by sensitive testing measures are unlikely to cause PE and may not require aggressive treatment.

The problem is lack of consensus on who should be treated and how to identify and manage blood clots that may not merit aggressive response, according to the article published in the September 2012 issue of the Journal of the American Academy of Orthopaedic Surgeons. That is especially an issue with the widespread use of computerized tomography pulmonary angiograms, which can detect smaller clots which could resolve without use of anticoagulants, the authors argue.

“Some recent studies have shown that while the incidence of diagnosis of pulmonary embolism is increasing, there is not a corresponding increase in mortality,” said lead author Paul Tornetta, MD. “What this suggests is that not all clots have the same clinical relevance—that is, they may not require the same aggressive level of blood thinners for treatment—and that increasingly sensitive tests may be picking up small, relatively insignificant clots that would not necessarily require treatment.”

The authors from Boston University Medical Center note that orthopedic patients already are at greater risk for postoperative bleeding, and anticoagulants increase that risk.

They suggest that broader criteria should be used when screening orthopaedic surgery and trauma patients for potentially dangerous clots before beginning anticoagulant therapy. “The size and location of a clot or clots may matter when deciding on management,” according to the article. “A risk-benefit evaluation can assist in deciding treatment.”

The study cited several factors that can increase a patient's chances of developing blood clots and PE, including:

• Older age
• Use of oral contraceptives
• Having a personal or family history of PE
• Undergoing extensive or prolonged surgical procedures
• Undergoing a lengthy period of immobilization following surgery or trauma

Tornetta called for the development of new guidelines to help “more accurately identify which patients could benefit from anticoagulant therapy and help to balance the risks of aggressive anticoagulation.”

“While it's clear that the use of blood thinners is of paramount importance in treating clinically relevant PE to prevent death,” he said, “it is also becoming clear that many of these patients may not need the same aggressive level of these medications, which could substantially reduce their risks of bleeding problems.”

U.S. Pharmacist Social Connect