title: Towards evidence-based emergency medicine: best BETs from the Manchester Royal Infirmary . BET 1: Do patients with an asymptomatic sub-segmental pulmonary embolism need anticoagulation therapy?
abstract: A short cut review was carried out to establish whether therapeutic anticoagulation is required for patients who have an incidental diagnosis of subsegmental pulmonary embolism (PE), which is asymptomatic. 4 studies were relevant to the three-part question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. The evidence suggests that patients with clinically unsuspected PE may have better prognostic outcomes than those with symptomatic presentations, especially if the PE is at the sub-segmental level. The only direct comparison of anti-coagulation versus no anti-coagulation in patients with an asymptomatic, unsuspected PE suggests a survival benefit from anti-coagulation. However, this study included patients with cancer and was not restricted to patients with subsegmental PE. Consequently, the clinical bottom line is that level 1 evidence is required to answer this question. In the meantime decisions must continue to be informed by clinical judgment.
authors.forename: Hyun
authors.initials: H
authors.lastname: Choi
authors.forename: Christopher
authors.initials: C
authors.lastname: Morgan
mesh_terms: D000925:Anticoagulants / Q000627:therapeutic use*; D004636:Emergency Service, Hospital; D055416:Evidence-Based Emergency Medicine; D006801:Humans; D011655:Pulmonary Embolism / Q000188:drug therapy*
chemical_list: D000925:Anticoagulants
keywords: emergency departments