ÎIf risk stratification is not performed in patients with suspected first LE DVT, use one of the following initial tests rather than no testing (1-B) or venography (1-B) or D-dimer testing (2-B).
• Proximal CUS or • Whole-leg US Whole-leg US may be preferred to proximal CUS in patients unable to return for serial testing and those with severe symptoms consistent with calf DVT or risk factors for extension of distal DVT.
ÎPatients with a negative proximal CUS should undergo testing with a moderate- or high-sensitivity D-dimer, whole-leg US, or repeat proximal CUS in 1 week rather than no further testing (1-B) or venography (2-B).
In patients with a negative proximal CUS, D-dimer is preferred over routine serial CUS (2-B) or whole-leg US (2-C). Patients with a single negative proximal CUS and positive D-dimer should undergo further testing with repeat proximal CUS in 1 week or whole-leg US rather than avoiding further testing (1-B for both comparisons).
ÎIn patients with negative serial proximal CUS or a negative D-dimer following a negative initial proximal CUS or negative whole-leg US no further testing is preferred over venography (1-B).
ÎIf proximal CUS is positive for DVT, treat rather than confirm with venography (1-B).
ÎIf isolated distal DVT is detected on whole-leg US, use serial testing to rule out proximal extension rather than proceeding to treatment (2-C).
▶ Patients with severe symptoms and risk factors for extension as outlined in Perioperative Management of Antithrombotic Therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines are more likely to benefit from treatment over repeat US.
▶ Patients who place a high value on avoiding the inconvenience of repeat testing and a low value on avoiding treatment of false positive results are more likely to choose treatment over repeat US.
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