Deep vein thrombosis: thromboses were usually extensive.

Clinical bottom line (level 2c)

  1. A third of patients with suspected first episode of deep vein thrombosis had it confirmed by venogram.
  2. No patients in this cohort had deep vein thrombosis just in the femoral or iliac veins: "2-point" ultrasound scnning is sufficent
Cogo et al: Archives of Internal Medicine 1993; 153: 2777-2780
Expires May 2003

The study

Outcome study with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: three university hospitals, Holland, Italy, Canada

562 patients (aged range 17 to 86 years; mean 51, 60% female) first episode of deep vein thrombosis confirmed by venogram (a contrast filling defect in more than one view)



Outcomes studied:
  • inadequate scan
  • deep vein thrombosis
  • proximal deep vein thrombosis
  • calf deep vein thrombosis
  • DVT isolated to the superficial femoral, common femoral or ileac veins (could be overlooked by "2 point" ultasound scanning)

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)    		 NNF
    (95% CI)
    inadequate scan ? 20/562 3.56%
    (2.03% to 5.09%)    		 28
    (20 to 49)
    deep vein thrombosis ? 189/562 33.6%
    (29.7% to 37.5%)    		 3
    (3 to 3)
    proximal deep vein thrombosis ? 166/562 29.5%
    (25.8% to 33.3%)    		 3
    (3 to 4)
    calf deep vein thrombosis ? 23/562 4.09%
    (2.46% to 5.73%)    		 24
    (17 to 41)
    DVT isolated to the superficial femoral, common femoral or ileac veins ? 0/562 0%
    (0% to 0%)

    Comments

    1. Length or position of symptoms did not correlate with the position of DVT.
    2. This suggests that ultrasound scanning of the leg can be confined to popliteal vein and trification.

    Citation

    1. Cogo A, Lensing AWA, Prandoni P, et al: Distribution of thrombosis in patients with symptomatic deep vein thrombosis: implications for simplifying the diagnostic process with compression ultrasound. Archives of Internal Medicine 1993; 153: 2777-2780
    Contributor: Chris Ball and Clare Wotton, May 2000
    Reviewer: Alex Gallus

    Clinical Question.
    Patient deep vein thombosis
    Intervention or Exposure prevalence, ultrasound at 2 points
    Outcome proximal or calf DVT, confirmed DVT