title: Should pulmonary embolism be suspected in exacerbation of chronic obstructive pulmonary disease?
abstract: BACKGROUND
  The cause of acute exacerbation of chronic obstructive pulmonary disease (COPD) is often difficult to determine. Pulmonary embolism may be a trigger of acute dyspnoea in patients with COPD.
  
  
  OBJECTIVE
  To determine the prevalence of pulmonary embolism in patients with acute exacerbation of COPD.
  
  
  METHODS
  123 consecutive patients admitted to the emergency departments of two academic teaching hospitals for acute exacerbation of moderate to very severe COPD were included. Pulmonary embolism was investigated in all patients (whether or not clinically suspected) following a standardised algorithm based on d-dimer testing, lower-limb venous ultrasonography and multidetector helical computed tomography scan.
  
  
  RESULTS
  Pulmonary embolism was ruled out by a d-dimer value <500 microg/l in 28 (23%) patients and a by negative chest computed tomography scan in 91 (74%). Computed tomography scan showed pulmonary embolism in four patients (3.3%, 95% confidence interval (CI), 1.2% to 8%), including three lobar and one sub-segmental embolisms. The prevalence of pulmonary embolism was 6.2% (n = 3; 95% CI, 2.3% to 16.9%) in the 48 patients who had a clinical suspicion of pulmonary embolism and 1.3% (n = 1; 95% CI, 0.3% to 7.1%) in those not suspected. In two cases with positive computed tomography scan, the venous ultrasonography also showed a proximal deep-vein thrombosis. No other patient was diagnosed with venous thrombosis.
  
  
  CONCLUSIONS
  The prevalence of unsuspected pulmonary embolism is very low in patients admitted in the emergency department for an acute exacerbation of their COPD. These results argue against a systematic examination for pulmonary embolism in this population.
authors.affiliation: Division of General Internal Medicine, Department of Medicine, Geneva University Hospitals, 24 rue Micheli-du-Crest, 1211 Geneva 14, Switzerland. olivier.rutschmann@hcuge.ch
authors.forename: Olivier T
authors.initials: OT
authors.lastname: Rutschmann
authors.forename: Jacques
authors.initials: J
authors.lastname: Cornuz
authors.forename: Pierre-Alexandre
authors.initials: PA
authors.lastname: Poletti
authors.forename: Pierre-Olivier
authors.initials: PO
authors.lastname: Bridevaux
authors.forename: Olivier W
authors.initials: OW
authors.lastname: Hugli
authors.forename: Salah D
authors.initials: SD
authors.lastname: Qanadli
authors.forename: Arnaud
authors.initials: A
authors.lastname: Perrier
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000378:metabolism; D006801:Humans; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications*; D011655:Pulmonary Embolism / Q000150:complications* / Q000000981:diagnostic imaging / Q000453:epidemiology; D012307:Risk Factors; D014057:Tomography, X-Ray Computed
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D