Definitions for the quality of evidence (high, moderate, low, very low) and strength of recommendations (strong, weak, further research) are repeated at the end of the Major Recommendations.
Use of Ultrasound for the Diagnosis of Deep Venous Thrombosis in Asymptomatic Patients
- Routine thromboprophylaxis instead of ultrasound surveillance should be the cornerstone of venous thromboembolic event (VTE) prevention in asymptomatic inpatients. The Anticoagulation Task Force provides guidelines for routine thromboprophylaxis. (Strong Recommendation, Moderate to Low Quality Evidence)
- Ultrasound surveillance of the bilateral proximal lower extremities may be most appropriate in situations where thromboprophylaxis is not possible. (Weak Recommendation, Very Low Quality Evidence)
- Ultrasound surveillance of the bilateral proximal lower extremities may also be appropriate in patients at the highest risk of deep venous thrombosis (DVT) or pulmonary embolism (PE) despite thromboprophylaxis (i.e., spinal cord injury patients, major trauma patients with high severity scores, and the highest risk orthopedic patients), and should likely be performed no more frequently than approximately once weekly. (Weak Recommendation, Very Low Quality Evidence)
- Color duplex ultrasound has adequate sensitivity and specificity to diagnose DVT in asymptomatic inpatients, and should be the test of choice for the diagnosis of DVT in asymptomatic inpatients when compared with D-Dimer assays or risk scores based on history and physical. (Strong Recommendation, Moderate Quality Evidence)
- D-Dimer assays should not be used to diagnose DVT in asymptomatic inpatients. (Strong Recommendation, Moderate Quality Evidence)
Definitions:
Quality of Evidence
The following grades of overall quality developed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) working group were used to grade the overall quality of evidence for each outcome:
High - Further research is very unlikely to change confidence in the estimate of effect
Moderate - Further research is likely to impact confidence in the estimate of effect and may change the estimate
Low - Further research is very likely to impact confidence in the estimate of effect and is likely to change the estimate
Very low - Any estimate of effect is very uncertain
Strength of Recommendations
Strong - Test should or should not be used for routine surveillance of deep venous thrombosis (DVT)
Weak - Test may be useful for surveillance of DVT in certain circumstances
Further research - No evidence exists for the usefulness of test in surveillance of DVT
