Table 1—

Characteristics of 246 chronic obstructive pulmonary disease patients according to usage of oxygen continuous oxygen therapy# (COT) versus noncontinuous oxygen therapy (NCOT)

Subjects nCOT§NCOTƒ
Age yrs68.4±8.771.6±7.4
Sex female %56.848.8
Current smoker %24516.020.5
Body mass index kg·m−222822.0±6.022.0±4.6
Had outdoor activity %24266.072.3
Systemic corticosteroid %24550.944.0
FEV1 % pred value11429.6±10.730.2±10.9
Prescribed oxygen flow L·min−11.3±0.61.3±0.7
Pa,O2, mmHg+6.38±0.76.36±0.9
Pa,CO2, mmHg+6.78±1.26.49±1.4
Time spent with oxygen according to the patient h18.5±3.48.2±4.8
Liquid oxygen %2459.34.8
Concentrator %24579.679.8
Mobile oxygen %24549.729.8
  • Data are presented as mean±sd unless otherwise stated

  • FEV1: forced expiratory volume in one second

  • Pa,O2: oxygen tension in arterial blood, COT=48.0 (5.3) mmHg, NCOT=47.8 (7.1) mmHg

  • Pa,CO2: carbon dioxide tension in arterial blood, COT=51.0. (9.0) mmHg, NCOT=48.8 (10.5) mmHg

  • §: n=162

  • ƒ: n=84

  • #: 15–24 h·day−1

  • : <15 h·day−1

  • +: 20 patients had only blood gases measured while on supplemental oxygen