Clinical question: How frequent is pulmonary embolism (PE) in patients with unexplained acute chronic obstructive pulmonary disease (COPD) exacerbation?
Background: Acute COPD exacerbations are highly inflammatory states, and since there is a well-known interaction between inflammatory pathways and thrombosis, PE occurs with increased prevalence, ranging from 18% to 25%. In approximately 30% of cases of acute exacerbations of COPD, no clear etiology is found.
Study design: Systematic review.
Setting: U.S. hospitals and EDs.
Synopsis: PE prevalence was 16.1% (95% CI, 8.3%-25.8%) in patients with unexplained COPD exacerbations. Thirty-two percent were subsegmental, 35% affected one of the main pulmonary arteries, and 32% were located in the lobar and interlobar arteries. Heterogeneity between the included studies was high. In-hospital and 1-year mortality were increased in patients with PE and COPD exacerbations in one study but not in another.
Signs of cardiac failure, hypotension, and syncope were more frequently found in patients with COPD exacerbation and PE, compared with patients with COPD exacerbation without PE.
Bottom line: PE is a common occurrence in patients with unexplained COPD exacerbations; two-thirds of those emboli involved segmental circulation and therefore were clinically relevant.
Citation: Aleva FE, Voets LW, Simons SO, de Mast Q, van der Ven A, Heijdra YF. Prevalence and localization of pulmonary embolism in unexplained acute exacerbations of COPD: a systematic review and meta-analysis [published online ahead of print Aug. 11, 2016]. doi: 10.1016/j.chest.2016.07.034.
Dr. Giese is an assistant professor at the University of Miami Miller School of Medicine and a hospitalist at the University of Miami Hospital and Jackson Memorial Hospital.