RT Journal Article
SR Electronic
T1 Using venous blood gas analysis in the assessment of COPD exacerbations: a prospective cohort study
JF Thorax
JO Thorax
FD BMJ Publishing Group Ltd and British Thoracic Society
SP 210
OP 215
DO 10.1136/thoraxjnl-2015-207573
VO 71
IS 3
A1 Tricia M McKeever
A1 Glenn Hearson
A1 Gemma Housley
A1 Catherine Reynolds
A1 William Kinnear
A1 Tim W Harrison
A1 Anne-Maree Kelly
A1 Dominick E Shaw
YR 2016
UL http://thorax.bmj.com/content/71/3/210.abstract
AB Introduction Identifying acute hypercapnic respiratory failure is crucial in the initial management of acute exacerbations of COPD. Guidelines recommend obtaining arterial blood samples but these are more difficult to obtain than venous. We assessed whether blood gas values derived from venous blood could replace arterial at initial assessment.Methods Patients requiring hospital treatment for an exacerbation of COPD had paired arterial and venous samples taken. Bland–Altman analyses were performed to assess agreement between arterial and venous pH, CO2 and . The relationship between SpO2 and SaO2 was assessed. The number of attempts and pain scores for each sample were measured.Results 234 patients were studied. There was good agreement between arterial and venous measures of pH and (mean difference 0.03 and −0.04, limits of agreement −0.05 to 0.11 and −2.90 to 2.82, respectively), and between SaO2 and SpO2 (in patients with an SpO2 of >80%). Arterial sampling required more attempts and was more painful than venous (mean pain score 4 (IQR 2–5) and 1 (IQR 0–2), respectively, p<0.001).Conclusions Arterial sampling is more difficult and more painful than venous sampling. There is good agreement between pH and values derived from venous and arterial blood, and between pulse oximetry and arterial blood gas oxygen saturations. These agreements could allow the initial assessment of COPD exacerbations to be based on venous blood gas analysis and pulse oximetry, simplifying the care pathway and improving the patient experience.