title: Diagnostic accuracy of noninvasive end-tidal carbon dioxide measurement in emergency department patients with suspected pulmonary embolism84-90.
abstract: OBJECTIVE
  Pulmonary embolism (PE) is a frequent health problem representing a diagnostic challenge with high mortality and morbidity rates. The aim of this study was to investigate the value of end-tidal carbon dioxide (ETCO2) and alveolar dead space fraction (ADSF) in the diagnosis of PE.
  
  
  METHODS
  ETCO2 levels of patients with suspected PE were measured with a noninvasive mainstream sensor. ADSF of patients was calculated and PaCO2 levels were also obtained. ROC curve analysis was used to determine diagnostic values of ETCO2 and ADSF for PE.
  
  
  RESULTS
  The study included 159 patients. The mean values for ETCO2 and ADSF were 16.27 (95% CI, 14.52-18.03) and 0.48 (95% CI, 0.43-0.539) in the PE group and 21.57 (95% CI, 20.52-22.639) and 0.35 (95% CI, 0.32-0.38) in the non-PE group. The area under the curve (AUC) and the cut-off point for ETCO2 were found as 0.751 and ≤19, with 83.8% sensitivity and 61.5% specificity. AUC and cut-off point for ADSF were found as 0.738 and >0.443, with 67.57% sensitivity and 73.77% specificity.
  
  
  CONCLUSIONS
  The diagnostic value of calculated ADSF and noninvasive bedside ETCO2 for PE was found to be low.
authors: Department of Emergency Medicine, Diyarbakır Research and Training Hospital, Diyarbakır, Turkey.
authors: Melih
authors: M
authors: Yüksel
authors: Department of Emergency Medicine, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey.
authors: Murat
authors: M
authors: Pekdemir
authors: Department of Emergency Medicine, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey.
authors: Serkan
authors: S
authors: Yilmaz
authors: Department of Emergency Medicine, Faculty of Medicine, Kocaeli University, Kocaeli, Turkey.
authors: Elif
authors: E
authors: Yaka
authors: Department of Emergency, SEKA State Hospital, Kocaeli, Turkey.
authors: Aslı Gülfer
authors: AG
authors: Kartal
mesh_terms: D002245:Carbon Dioxide / Q000032:analysis*; D004636:Emergency Service, Hospital; D006801:Humans; D011446:Prospective Studies; D011655:Pulmonary Embolism; D012680:Sensitivity and Specificity
chemical_list: D002245:Carbon Dioxide
keywords: Pulmonary embolism; alveolar dead space fraction; emergency department; end-tidal carbon dioxide