Podcast 997: D-Dimer

D-dimer testing serves as a critical diagnostic tool in the emergency department to efficiently rule out serious vascular conditions without resorting to advanced imaging. While a standard threshold of 500 ng/mL typically excludes blood clots in low-risk patients, the YEARS score allows for a higher cutoff of 1,000 ng/mL if specific criteria—no hemoptysis, no signs of deep vein thrombosis, and pulmonary embolism not being the primary diagnosis—are met. Beyond venous thromboembolism, the D-dimer is also effective for excluding aortic dissections when used alongside the Aortic Dissection Detection Risk Score (ADDRS). In patients with only one high-risk factor or physical finding, a D-dimer result under 500 ng/mL provides sufficient evidence to rule out a dissection. Utilizing these evidence-based thresholds and clinical decision rules streamlines patient care, reduces unnecessary radiation exposure from CT scans, and accelerates the discharge process for low-risk individuals.