New guidelines by the American College of Physicians recommend doctors individually assess the risk of thromboembolism or bleeding problems in patients hospitalized for medical illnesses including stroke before starting treatment to prevent venous thromboembolism.
Most hospitalized patients are at risk for developing venous thromboembolism (VTE), a serious clinical problem that is a combination of pulmonary embolism (PE) and deep venous thrombosis (DVT).
Doctors have used blood thinners, such as heparin, as well as mechanical prophylaxis with graduated compression stockings to prevent VTE. However, these treatments carry risks such as causing bleeding problems.
Dr. Amir Qaseem
In a written statement, Dr. Amir Qaseem, one of the guideline’s authors and the director of clinical policy at the ACP, said that "the evidence does not support routine VTE prophylaxis in patients hospitalized for medical illnesses, including stroke." He said that for patients at risk of VTE, physicians should "prescribe heparin or related blood thinners, unless the assessed risk of bleeding outweighs likely benefits."
According to a meta-analysis led by Dr. Frank A. Lederle of the Center for Chronic Disease Outcomes Research, Minneapolis Veterans Affairs Medical Center, which included 40 randomized trials involving more than 52,000 patients, heparin did not significantly reduce total mortality but did reduce PEs with an odds ratio of 0.69. However, it also increased bleeding with a risk ratio of 1.34 (Ann. Intern. Med. 2011;155:602-15).
In most cases, the reduction in PEs will outweigh the risk in bleeding events, but doctors should evaluate each case individually, the guidelines state.
According to the ACP guidelines, mechanical prophylaxis with graduated compression stockings was not effective in preventing VTE or reducing mortality and resulted in clinically important lower extremity skin damage (Ann. Intern. Med. 2011;155:625-32).
Thus, pharmacologic prophylaxis with heparin or related drugs is recommended for VTE in medical patients including those with stroke unless the risk for bleeding outweighs the probable benefits, according to the guidelines. For patients at risk for bleeding or for whom heparin is contraindicated for other reasons, intermittent pneumatic compression may be the best option, although research is still ongoing on its effectiveness.
The ACP guidelines do not recommend performance measures that promote universal VTE prophylaxis for patients, as they do not take into account each individual’s risk level.
Dr. Linda L. Humphrey, one of the guideline’s authors, has served as a consultant for the U.S. Preventive Services Task Force and received royalties from UpToDate. Another author, Dr. Paul Shekelle, has served as a consultant for the ECRI Institute and been employed at the Department of Veterans Affairs, as well as received grants or has grants pending from the Agency for Healthcare Research and Quality, the Department of Veterans Affairs, and the Centers for Medicare & Medicaid Services. Finally, he also has received royalties from UpToDate.