If clinical gestalt for PE is low, use PERC to rule out PE. If not ruled out, use a validated tool to determine pretest probability of PE: Wells, Revised Geneva, or simplified versions of either score. If non-high or "unlikely" pretest probability, order D-dimer, adjusting for age (<500 or <age x 10). If D-dimer is negative, PE is ruled out. If positive, order CT pulmonary angiogram. For more, check out the peer-reviewed lecture I did for Academic Emergency Medicine, PE Workup in 5 Steps.
Why does this matter?
Indiscriminate workup for PE results in over-testing, with resultant exposure to ionizing radiation and IV contrast, as well as expense.
From the experts
This review of the diagnosis of PE was written by some of the world's experts in this condition. They emphasize the systematic approach outlined in the Spoon Feed above but also caution about working up patients for PE unnecessarily. The 3 clinical presentations of pleuritic chest pain, dyspnea, or syncope/shock are most common. They touch on upcoming studies using higher D-dimer cutoffs in low probability patients and emphasize the safety of the age-adjusted approach. The Spoon Feed today distills this paper into 5 sentences.
Diagnosis of acute pulmonary embolism. J Thromb Haemost. 2017 Jul;15(7):1251-1261. doi: 10.1111/jth.13694.
It is hard to recall the PE workup. A great free resource is Evidence Care.
Peer reviewed by Thomas Davis, MD.