title: Is a V/Q scan based algorithm correctly used to diagnose acute pulmonary embolism? A daily practice survey.
abstract: BACKGROUND
  Diagnostic flow-charts for pulmonary embolism (PE) are widely implemented in the management of PE. A major drawback of a diagnostic PE algorithm is the use of several consecutive tests, which may be challenging in daily clinical practice.
  
  
  METHODS
  Evaluation whether the use of an algorithm, starting with a ventilation/perfusion (V/Q) scan after a normal chest X-ray, is correctly used in daily clinical practice for diagnosing acute PE. Consecutive V/Q scans of patients with suspected acute PE were assessed to evaluate the use of the predefined diagnostic algorithm.
  
  
  RESULTS
  A chest X-ray had been performed in 101 of the 130 patients who underwent V/Q scanning; 89 patients had a normal chest X-ray. The V/Q scan was normal in 77/130 patients (59%), 30/130 patients (23%) had a non-high probability and 23/130 patients (18%) a high probability for PE. Only 3 of the 30 patients with a non-high V/Q scan (10%) underwent a computed tomographic pulmonary angiography (CTPA) scan, in contrast to the algorithm that required a CTPA scan in every patient with a non-high V/Q scan. Overall, the diagnostic strategy, starting with a V/Q scan as the baseline diagnostic tool with a prior chest X-ray, was appropriately followed in only 75/101 patients (74%).
  
  
  CONCLUSIONS
  A complex diagnostic algorithm for diagnosing PE is often not followed properly. This improper use of an algorithm could lead to a potential delay of establishing or excluding PE, a delay of therapy and/or unnecessary treatment. More simple algorithms could resolve this diagnostic management dilemma.
authors.affiliation: Department of General Internal Medicine, Section of Vascular Medicine, Leiden University Medical Center, Leiden, The Netherlands. k.a.kortekaas@lumc.nl
authors.forename: Kirsten A
authors.initials: KA
authors.lastname: Kortekaas
authors.forename: Jeroen
authors.initials: J
authors.lastname: Eikenboom
authors.forename: Marcel P M
authors.initials: MP
authors.lastname: Stokkel
authors.forename: Hestia
authors.initials: H
authors.lastname: van Gent
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.forename: Menno V
authors.initials: MV
authors.lastname: Huisman
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D005260:Female; D006801:Humans; D008168:Lung / Q000473:pathology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000175:diagnosis* / Q000503:physiopathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods; D014692:Ventilation-Perfusion Ratio; D055815:Young Adult