0
Summaries for Patients |

Safely Ruling Out Deep Venous Thrombosis in Primary Care FREE

[+] Article and Author Information

The summary below is from the full report titled “Safely Ruling Out Deep Venous Thrombosis in Primary Care.” It is in the 17 February 2009 issue of Annals of Internal Medicine (volume 150, pages 229-235). The authors are H.R. Büller, A.J. ten Cate-Hoek, A.W. Hoes, M.A. Joore, K.G.M. Moons, R. Oudega, M.H. Prins, H.E.J.H. Stoffers, D.B. Toll, E.F. van der Velde, and H.C.P.M. van Weert, for the AMUSE (Amsterdam Maastricht Utrecht Study on thromboEmbolism) Investigators.


Ann Intern Med. 2009;150(4):I-36. doi:10.7326/0003-4819-150-4-200902170-00001
Text Size: A A A

What is the problem and what is known about it so far?

Blood clots in the large veins of the leg (called deep venous thrombosis) can cause serious problems. If pieces of clot break off, they can travel through the bloodstream to the lungs where they block part of the circulation through the lung, strain the heart, and interfere with allowing oxygen into the blood. Even when clots do not break off, they can damage the leg veins and cause painful leg swelling. Treatment with warfarin (a blood thinner) reduces the risk for these serious complications. Because too much warfarin causes serious bleeding events, it is important to make an accurate diagnosis before treating.

The best way to diagnose blood clots in the leg veins is to make an image with an ultrasound scan. This test is expensive and is usually available only in a hospital. Because most patients with suspected clots in the leg veins first seek care in the doctor's office, a method that allows some patients to avoid ultrasonography would probably save money and be more convenient.

Why did the researchers do this particular study?

The researchers developed a method to identify patients who probably did not have a blood clot and had proved that this method worked in hospital practice. They wanted to see whether primary care doctors could successfully use the method in office practice. Their method used information from the patient's history, examination, and a blood test for clotting (called d-dimer). They used an in-office d-dimer test that provided results in a few minutes.

Who was studied?

1028 patients (in 300 practices) who were suspected of having blood clots in the leg veins.

How was the study done?

The doctors asked the patient about factors related to blood clots, examined the patient, and did the d-dimer test. Each finding had a number that indicated how much the suspicion of blood clots was increased. The doctors added up the numbers for the findings that were present in a patient. A patient with a low total score had only a small chance of having blood clots, therefore, the patient was not sent to the hospital for ultrasound scanning and the doctor did not prescribe warfarin. Three months later, the researchers asked these low-risk patients if they had problems in the legs or lungs suspicious of a blood clot.

What did the researchers find?

Half of all patients had a low score, and thus did not have an ultrasound scan or receive warfarin. They had only a 1.4% chance of having a blood clot during the 3 months after seeing the doctor.

What were the limitations of the study?

The researchers could have missed some low-risk patients who developed blood clots after the doctor decided not to treat them.

What are the implications of the study?

Doctors can use clinical findings and the d-dimer test in a setting outside of the hospital to identify patients who are unlikely to have blood clots in the leg veins and do not need treatment.

Figures

Tables

References

Letters

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Comments

Submit a Comment
Submit a Comment

Summary for Patients

Clinical Slide Sets

Terms of Use

The In the Clinic® slide sets are owned and copyrighted by the American College of Physicians (ACP). All text, graphics, trademarks, and other intellectual property incorporated into the slide sets remain the sole and exclusive property of the ACP. The slide sets may be used only by the person who downloads or purchases them and only for the purpose of presenting them during not-for-profit educational activities. Users may incorporate the entire slide set or selected individual slides into their own teaching presentations but may not alter the content of the slides in any way or remove the ACP copyright notice. Users may make print copies for use as hand-outs for the audience the user is personally addressing but may not otherwise reproduce or distribute the slides by any means or media, including but not limited to sending them as e-mail attachments, posting them on Internet or Intranet sites, publishing them in meeting proceedings, or making them available for sale or distribution in any unauthorized form, without the express written permission of the ACP. Unauthorized use of the In the Clinic slide sets will constitute copyright infringement.

Toolkit

Want to Subscribe?

Learn more about subscription options

Advertisement
Related Articles
Related Point of Care
Topic Collections
PubMed Articles

Want to Subscribe?

Learn more about subscription options

Forgot your password?
Enter your username and email address. We'll send you a reminder to the email address on record.
(Required)
(Required)