HealthDay News — Using the Wells rule for pulmonary embolism in combination with either a qualitative point-of-care D-dimer test or a quantitative D-dimer test helps practitioners safety exclude pulmonary embolism, study findings indicate.
To compare the accuracy of a strategy using the Wells rule combined with either a qualitative point-of-care (POC) D-dimer test performed in primary care or a quantitative laboratory based D-dimer test, Wim Lucassen, MD, PhD, of the Academic Medical Center in Amsterdam, and colleagues evaluated data from a prospective cohort of 598 adults suspected of pulmonary embolism in primary care.
Clinicians scored the Wells rule and carried out a qualitative POC test. All patients were referred to hospital for reference testing. Quantitative D-dimer tests were performed in hospital laboratories. The prevalence of venous thromboembolism in low-risk patients was the primary outcome.
The prevalence of pulmonary embolism was 12.2%, reported the researchers in the Journal of Thrombosis and Haemostasis. The quantitative test and POC test missed one (0.4%) and four patients (1.5%), respectively, with a negative strategy (Wells ≤4 points and D-dimer test negative; P=0.20). With the POC test, 23 more patients could be excluded (4%; P=0.05).
Combining the Wells rule and a POC yielded a sensitivity and specificity of 94.5% and 51.0%, respectively, which when combined with a quantitative test changed to 98.6% and 47.2%, respectively.
Providers “can safely exclude pulmonary embolism using the Wells rule for pulmonary embolism in combination with either a qualitative POC D-dimer test or a quantitative D-dimer test,” concluded the scientists.
“A prospective diagnostic impact study, where patient management is actually guided by the Wells rule and the D-dimer test (either quantitative or POC, qualitative), is needed to further evaluate the feasibility of this strategy in primary care.”