RT Journal Article
SR Electronic
T1 Oximetry neither to prescribe long-term oxygen therapy nor to screen for severe hypoxaemia
JF ERJ Open Research
JO erjor
FD European Respiratory Society
SP 00272-2021
DO 10.1183/23120541.00272-2021
VO 7
IS 4
A1 Yves Lacasse
A1 Sébastien Thériault
A1 Benoît St-Pierre
A1 Sarah Bernard
A1 Frédéric Sériès
A1 Harold Jean Bernatchez
A1 François Maltais
YR 2021
UL http://openres.ersjournals.com/content/7/4/00272-2021.abstract
AB Background and objective Transcutaneous pulse oximetry saturation (SpO2) is widely used to diagnose severe hypoxaemia and to prescribe long-term oxygen therapy (LTOT) in COPD. This practice is not based on evidence. The primary objective of this study was to determine the accuracy (false positive and false negative rates) of oximetry for prescribing LTOT or for screening for severe hypoxaemia in patients with COPD.Methods In a cross-sectional study, we correlated arterial oxygen saturation (SaO2) and SpO2 in patients with COPD and moderate hypoxaemia (n=240) and calculated the false positive and false negative rates of SaO2 at the threshold of ≤88% to identify severe hypoxaemia (arterial oxygen tension (PaO2) ≤55 mmHg or PaO2 <60 mmHg) in 452 patients with COPD with moderate or severe hypoxaemia.Results The correlation between SaO2 and SpO2 was only moderate (intra-class coefficient of correlation: 0.43; 95% confidence interval: 0.32–0.53). LTOT would be denied in 40% of truly hypoxaemic patients on the basis of a SaO2 >88% (i.e., false negative result). Conversely, LTOT would be prescribed on the basis of a SaO2 ≤88% in 2% of patients who would not qualify for LTOT (i.e., false positive result). Using a screening threshold of ≤92%, 5% of severely hypoxaemic patients would not be referred for further evaluation.Conclusions Several patients who qualify for LTOT would be denied treatment using a prescription threshold of saturation ≤88% or a screening threshold of ≤92%. Prescription of LTOT should be based on PaO2 measurement.Although transcutaneous pulse oximetry is widely used to diagnose severe hypoxaemia and prescribe long-term oxygen therapy in COPD, up to 40% of patients who qualify for this therapy would be denied treatment using the saturation threshold of ≤88% https://bit.ly/3jolWU5