Wells Score of DVT
Pulmonary embolism from deep venous thrombosis remains a leading killer. Many times intensivists are faced with the question of proceeding or not with further radiological workup. Although Wells score is not the absolute score to rule out DVT and subsequently the risk of PE (some literature argue against its validity), it still remains a strong quick tool while differential diagnosis with other conditions. It has been said that if the score of low-probability is combined with negative d-dimer, the negative predictive value is 99.5% 1. In other words, you can safely hold on further radiological workup.
3 points if objective signs like localized tenderness, asymmetric calf swelling.
1.5 points if Heart Rate more than 100 beats/min
1.5 points if bedridden for more than 3 days or major surgery within 4 weeks
1.5 points if previous 'documented' diagnosis of DVT or PE
1 point if hemoptysis
1 point if active cancer
3 points if high clinical suspicion of PE (on overall clinical and lab. findings).
- 0 - 2 low probability,
- 2-6 moderate probability,
- 3-6 high probability
low-probability + negative d-dimer = -ve predictive value of not having DVT is 99.5%
Related previous pearl: What if even thrombolysis fails in massive PE ?
Reference: click to get abstract/article
Excluding Pulmonary Embolism at the Bedside without Diagnostic Imaging: Management of Patients with Suspected Pulmonary Embolism Presenting to the Emergency Department by Using a Simple Clinical Model and D-dimer Philip S. Wells and coll.,Ann Intern Med 2001;135:98-107