UNIGE document Scientific Article
previous document  unige:21372  next document
add to browser collection

Volumetric or time-based capnography for excluding pulmonary embolism in outpatients?

Verschuren, F.
Heinonen, E.
Le Gal, G.
Meyer, G.
Thys, F.
Published in Journal of Thrombosis and Haemostasis. 2010, vol. 8, no. 1, p. 60-67
Abstract BACKGROUND: Volumetric capnography is technically more demanding but theoretically better than the time-based alveolar deadspace fraction (P(a)CO(2) - EtCO(2))/P(a)CO(2) as a bedside diagnostic tool for excluding pulmonary embolism (PE) in outpatients. OBJECTIVE: We compared both diagnostic accuracy in patients with a suspected PE and positive D-dimer enzyme-linked immunosorbent assay results. PATIENTS AND METHODS: In this clinical multicenter trial with prospective inclusion and 3-month follow-up, alveolar deadspace fraction was compared by receiver operating characteristic (ROC) analysis with other parameters derived from volumetric capnography. RESULTS: Capnography was performed in 239 patients, and 205 tests (86%) were conclusive. The incidence of PE was 33%. The alveolar deadspace fraction accuracy expressed with ROC curve analysis was 0.73 +/- 0.04. The diagnostic performances of parameters from volumetric capnography were not significantly better. Sixteen per cent [95% confidence interval (CI) 12-21%] of patients presented a (P(a)CO(2) - EtCO(2))/P(a)CO(2) ratio under the cut-off value of 0.15, with a low clinical probability. This combination excluded PE, with a sensitivity of 96% (95% CI 89-99%) and a negative likelihood ratio of 0.17 (95% CI 0.09-0.33%). CONCLUSION: Volumetric capnography failed to show superiority to alveolar deadspace fraction measurements [(P(a)CO(2) - EtCO(2))/P(a)CO(2)] for exclusion of PE in outpatients with positive D-dimer test results. Future studies should clarify the safety of excluding PE in patients combining low clinical probability with positive D-dimer results and (P(a)CO(2) - EtCO(2))/P(a)CO(2) ratios below the cut-off value of 0.15.
Keywords AgedAged, 80 and over*CapnographyCarbon Dioxide/*metabolismEnzyme-Linked Immunosorbent AssayEuropeFibrin Fibrinogen Degradation Products/metabolismHumansLikelihood FunctionsMiddle Aged*Outpatients*Point-of-Care SystemsPredictive Value of TestsProspective StudiesPulmonary Embolism/blood/*diagnosis/metabolismROC Curve*Respiratory Dead SpaceSensitivity and SpecificityTime Factors
PMID: 19874457
Full text
Research groups Groupe Perrier Arnaud (Médecine interne générale, de réhabilitation et de gériatrie) (585)
La maladie thromboembolique veineuse (808)
(ISO format)
VERSCHUREN, F. et al. Volumetric or time-based capnography for excluding pulmonary embolism in outpatients?. In: Journal of Thrombosis and Haemostasis, 2010, vol. 8, n° 1, p. 60-67. https://archive-ouverte.unige.ch/unige:21372

164 hits

0 download


Deposited on : 2012-05-23

Export document
Format :
Citation style :