FPIN’s Clinical Inquiries

What Clinical Findings Can Be Used to Diagnose Deep Venous Thrombosis?

Am Fam Physician. 2004 Aug 1;70(3):565-566.

Searchable Question

What clinical findings can be used to diagnose deep venous thrombosis (DVT)?

Evidence-Based Answer

No single clinical finding can accurately diagnose DVT. [Strength of recommendation: A, based on a systematic review of homogeneous validating cohort studies with good reference standards] However, when organized into clinical decision rules (CDRs), clinical findings can reliably differentiate patients into categories of low, moderate, or high probability of having DVT. [Strength of recommendation: A, based on numerous studies of CDRs from different clinical centers]

Evidence Summary

A 1998 systematic review1 concluded that individual signs and symptoms cannot reliably diagnose DVT. [Evidence level 1A] Combining specific risk factors, symptoms, and physical signs into a CDR increases diagnostic accuracy. The best-studied CDR is the Wells model (see accompanying table). The Agency for Healthcare Research and Quality (AHRQ) reported that the Wells CDR accurately classified patients per probability of DVT—low (zero to 13 percent chance), moderate (13 to 30 percent chance) or high (49 to 81 percent chance)—in 11 of 12 studies.2 [Evidence level 1A] The AHRQ report was limited in that all of the reviewed studies were published in the English language, most excluded patients with a history of DVT, and some had methodologic flaws.

The results of four recently published studies36 of the Wells CDR are consistent with the AHRQ findings. [References 3 through 6—Evidence level 1B] It is important to note that, when using only the Wells CDR, DVT cannot be ruled out completely in patients with a low probability score or confirmed in patients with a high probability score. However, use of such a CDR can help inform interpretation of subsequent diagnostic tests and reduce the need for invasive testing.

Table 1

Wells Clinical Decision Rule

Clinical characteristic Score

Active cancer (treatment ongoing or within previous six months or palliative)

1

Paralysis, paresis, or recent plaster immobilization of the lower extremities

1

Recently bedridden for more than three days or major surgery within 12 weeks requiring general or regional anesthesia

1

Localized tenderness along the distribution of the deep venous system

1

Entire leg swollen

1

Calf swelling 3 cm larger than asymptomatic side (circumference measured 10 cm below tibial tuberosity)

1

Pitting edema confined to the symptomatic leg

1

Collateral superficial veins (nonvaricose)

1

Previously documented DVT

1

Alternative diagnosis at least as likely as DVT

−2


note: To determine the probability of DVT, calculate the score and place the patient in one of the following categories: a score of zero = low (zero to 13 percent probability); 1 to 2 = moderate (13 to 30 percent probability); ≥ 3 = high (49 to 81 percent probability). In patients with symptoms in both legs, the more symptomatic leg is used. An additional characteristic, “previously documented DVT,” was added in 2003, but the new rule has not been extensively tested. DVT = deep venous thrombosis.

Information from references 1 and 2.

Table 1   Wells Clinical Decision Rule

View Table

Table 1

Wells Clinical Decision Rule

Clinical characteristic Score

Active cancer (treatment ongoing or within previous six months or palliative)

1

Paralysis, paresis, or recent plaster immobilization of the lower extremities

1

Recently bedridden for more than three days or major surgery within 12 weeks requiring general or regional anesthesia

1

Localized tenderness along the distribution of the deep venous system

1

Entire leg swollen

1

Calf swelling 3 cm larger than asymptomatic side (circumference measured 10 cm below tibial tuberosity)

1

Pitting edema confined to the symptomatic leg

1

Collateral superficial veins (nonvaricose)

1

Previously documented DVT

1

Alternative diagnosis at least as likely as DVT

−2


note: To determine the probability of DVT, calculate the score and place the patient in one of the following categories: a score of zero = low (zero to 13 percent probability); 1 to 2 = moderate (13 to 30 percent probability); ≥ 3 = high (49 to 81 percent probability). In patients with symptoms in both legs, the more symptomatic leg is used. An additional characteristic, “previously documented DVT,” was added in 2003, but the new rule has not been extensively tested. DVT = deep venous thrombosis.

Information from references 1 and 2.

The Wells CDR is more accurate than the Kahn and St. André CDRs and is comparable to the Ambulatory CDR.6 Two studies3,7 have shown that empirically assigning patients to low-, moderate-, or high-probability groups based on established clinical criteria is as accurate as formal use of the Wells CDR. [Reference 7—Evidence level 1B]

Recommendations from Others

The Finnish Medical Society recommends using a CDR that is similar to the Wells CDR during the initial evaluation of patients suspected of having DVT.8 The most recent American Thoracic Society guideline (published in 1999, before most of the studies evaluating CDRs for DVT were available), states that the clinical evaluation cannot be relied on to confirm or exclude the diagnosis of DVT.9

Clinical Commentary

Physicians should use this evidence to decide how aggressively to pursue the diagnosis of suspected DVT. For example, a patient with a low clinical probability of DVT and a normal initial noninvasive diagnostic test (d-dimer or ultrasonography) may require only observation, whereas a patient with a high clinical probability and a normal initial noninvasive diagnostic test may require serial ultrasonography or venography.

Department of Family Medicine, State University of New York Upstate Medical University, Syracuse, N.Y.

Address correspondence by e-mail to John Smucny, M.D., smucnyj@upstate.edu. Reprints are not available from the authors.

REFERENCES

1. Anand SS, Wells PS, Hunt D, Brill-Edwards P, Cook D, Ginsberg JS. Does this patient have deep vein thrombosis?. JAMA. 1998;279:1094-9.

2. Segal JB, Agency for Healthcare Research and Quality, Johns Hopkins University, Evidence-Based Practice Center. Diagnosis and treatment of deep venous thrombosis and pulmonary embolism. evidence report/technology assessment: no. 68. Rockville, Md.: U.S. Department of Health and Human Services, Public Health Service, Agency for Healthcare Research and Quality, 2003.

3. Miron MJ, Perrier A, Bounameaux H. Clinical assessment of suspected deep vein thrombosis: comparison between a score and empirical assessment. J Intern Med. 2000;247:249-54.

4. Anderson DR, Kovacs MJ, Kovacs G, Stiell I, Mitchell M, Khoury V, et al. Combined use of clinical assessment and D-dimer to improve the management of patients presenting to the emergency department with suspected deep vein thrombosis (the EDITED study). J Thromb Haemost. 2003;1:645-51.

5. Shields GP, Turnipseed S, Panacek EA, Melnikoff N, Gosselin R, White RH. Validation of the Canadian clinical probability model for acute venous thrombosis. Acad Emerg Med. 2002;9:561-6.

6. Constans J, Boutinet C, Salmi LR, Saby JC, Nelzy ML, Baudouin P, et al. Comparison of four clinical prediction scores for the diagnosis of lower limb deep venous thrombosis in outpatients. Am J Med. 2003;115:436-40.

7. Cornuz J, Ghali WA, Hayoz D, Stoianov R, Depairon M, Yersin B. Clinical prediction of deep venous thrombosis using two risk assessment methods in combination with rapid quantitative d-dimer testing. Am J Med. 2002;112:198-203.

8. Finnish Medical Society Duodecim. Deep venous thrombosis. Helsinki, Finland: Duodecim Medical, 2002.

9. Tapson VF, Carroll BA, Davidson BL, Elliott CG, Fedullo PF, Hales CA, et al. The diagnostic approach to acute venous thromboembolism. Clinical practice guideline. American Thoracic Society. Am J Respir Crit Care Med. 1999;160:1043-66.

Copyright Family Practice Inquiries Network. Used with permission.

 

Clinical Inquiries provide answers to questions submitted by practicing family physicians to the Family Practice Inquiries Network (FPIN). Members of the network select questions based on their relevance to family medicine. Answers are drawn from an approved set of evidence-based resources and undergo peer review. The strength of recommendations and the level of evidence for individual studies are rated using criteria developed by the Evidence-Based Medicine Working Group (http://www.cebm.net/levels_of_evidence.asp).

This series of Clinical Inquiries is coordinated for American Family Physician by John Epling, M.D., State University of New York Upstate Medical University, Syracuse, N.Y. The complete database of evidence-based questions and answers is copyrighted by FPIN. If you are interested in submitting questions to be answered or writing answers for this series, go to http://www.fpin.org or contact CI2Editor@fpin.org.


Want to use this article elsewhere? Get Permissions


Article Tools

  • Print page
  • Share this page
  • AFP CME Quiz

Information From Industry

More in AFP

More in Pubmed

Navigate this Article