Towards evidence based emergency medicine: best BETs from the Manchester Royal Infirmary. BET 2: Should we use an age adjusted D-dimer threshold in managing low risk patients with suspected pulmonary embolism?

A shortcut review was carried out to establish whether a higher age related threshold can be used when using d-dimer as a rule out test for pulmonary embolism. 29 papers were found of which 13 presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these best papers are tabulated. The clinical bottom line is that in older patients suspected of having a Pulmonary Embolus (PE), with a low pretest possibility, an age-adjusted D-dimer increases specificity with minimal change in the sensitivity, thereby increasing the number of patients who can be safely discharged without further investigations.