Guidelines introduce novel therapies for the prevention and treatment of thrombosis

Sep 14 2004

New antithrombotic guidelines from the American College of Chest Physicians (ACCP) introduce novel therapies for the prevention and treatment of thrombosis and, for the first time, offer specific recommendations for long-distance travelers. The guidelines also update previously issued recommendations and emphasize the overall need for stronger implementation of the guidelines in the clinical setting.

Over 500 evidence-based recommendations from The Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy were developed by a nationwide panel of 87 physicians and are published in the September supplement to CHEST, the official peer-reviewed publication of the ACCP. Antithrombotic and thrombolytic therapies are used to prevent thrombosis or blood clotting in an artery, vein, or the heart. Thrombosis can ultimately lead to potentially fatal blockage in the lung, known as venous thromboembolism (VTE).

“This is an exciting time for the field of thrombosis. Since the last guidelines were published in 2001, rigorous studies have resulted in new and stronger evidence-based recommendations for many indications, including those for stroke and coronary artery disease,” said Panel Chair Jack Hirsh, MD, FCCP, Henderson Research Center, Hamilton, ON, Canada. “The new guidelines not only offer an update of recommendations from previous years, but they also provide a look into the new therapies that are now available and a preview of groundbreaking therapies that are still in development.”

Approximately 230 new, graded recommendations have been added to the guidelines, including those related to new therapies and the prevention of thrombosis during long-distance travel. A new anticoagulant, fondaparinux, is recommended as a practical alternative to the standard anticoagulant, low-molecular-weight heparin (LMWH), for it does not compromise safety or effectiveness, yet has a longer half-life, a more predictable response, and fewer side effects than LMWH. Not mentioned in previous guidelines, fondaparinux also has received three of the strongest recommendations for the drug’s use during the orthopedic procedures of hip and knee arthroplasty.

For the first time, the guidelines include formal recommendations on how long-distance travelers can avoid thrombolytic events. Specific recommendations include:

• For flights longer than six hours, patients, with or without risk for VTE, should avoid constrictive clothing around the lower extremities and waist, avoid dehydration, and engage in frequent calf muscle stretching.
• Patients at risk for VTE should consider using a graduated compression stocking or receiving a dose of LMWH or fondaparinux prior to departure.
• Aspirin is not recommended for the prevention of VTE associated with travel.

“There is much speculation about the occurrence and treatment of deep vein thrombosis, or ‘economy class syndrome,’ that can occur in patients spending several hours on a plane,” said Dr. Hirsh. “Although prevention is often focused on at-risk patients, such as women who are pregnant or patients who have recently had surgery, we strongly advise all patients traveling on flights of more than six hours to take the necessary precautions to prevent thrombosis.”

The panel describes the guideline development process and the assessment and grading of the quality of evidence and strength of recommendations in separate chapters. The novel approach used to develop the evidence-based recommendations, is one of the important and defining features of these guidelines.

Panel members also dedicate an entire chapter to guideline application, which provides an overview of the importance of implementation and strategies for medical professionals and institutions to implement the guidelines into practice. Within the guidelines, panel members reviewed the inconsistencies involved in application of the guidelines and the resulting adverse events.

“Despite the overwhelming evidence that ACCP antithrombotic recommendations are effective, many physicians are inconsistent when applying the guidelines, which may lead to adverse events, “ said Panel Co-Chair Holger Schunemann, MD, PhD, University of Buffalo, Buffalo, NY. “The new recommendations for implementation offer health-care professionals ways of applying the guidelines to clinical practice that will help improve patient care outcomes in the process.” To improve guideline implementation, panel members recommend that considerable resources be dedicated to the distribution of physician and patient educational material about the guidelines, as well as automatic computer reminders for physicians prescribing antithrombotic therapies.

The guidelines also include revised and recurring recommendations for antithrombotic therapy, including those related to coronary artery disease and stroke. For coronary interventions, revised recommendations advise against the use of the antiplatelet ticlopidine when other treatments are available. Although recommended in previous guidelines as a first-line therapy, ticlopidine recently has been linked to many, and sometimes deadly, side effects. In addition, for most patients who suffer from unstable angina or a minor heart attack, the antiplatelet clopidogrel, in combination with aspirin, is recommended. For patients with non-heart-related stroke, panel members reinforce the previous guideline that the blood clot-dissolving agent, tissue plasminogen activator, be used only within three hours of stroke onset. In addition, guidelines recommended against the sole use of aspirin as a preventative therapy for thrombosis for any patient group.

“With each revision, the ACCP evidence-based antithrombotic guidelines become more refined and more relevant to each health-care specialty,” said Richard S. Irwin, MD, FCCP, President of the American College of Chest Physicians. “To ensure the most effective and patient-focused care, it is essential for all health-care providers to become familiar with the guidelines and take active steps to implement the guidelines in their practice.”

http://www.chestjournal.org