Oxygen in Chronic Respiratory Disease A Constant Companion or Just at Night

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Oxygen inChronic Respiratory DiseaseA
Constant Companion orJust at Night

• Dr. Roger Goldstein
• Professor of Medicine and Physical Therapy,
  University of Toronto
• West Park Healthcare Centre

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For COPD patients with resting hypoxemia some
oxygen is good and more is better
Composite slide - courtesy Dr. Yves Lacasse
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Although oxygen is life saving for patients with
resting hypoxemia, what is the role of ambulatory
oxygen in this population?
Ambulatory oxygen for those with resting hypoxemia

• Rationale for encouraging mobility as part of
  rehabilitation
• Might also increase compliance with
  LTOT-important as the oxygen effect is dose
  dependant
• Correction of exercise desaturation may increase
  exercise tolerance and improve autonomy

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Absence of change in dyspnea scores and exercise
capacity when ambulatory oxygen is added to a
stationary system
Lacasse Y, ERJ 2005251032
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Dyspnea and hyperoxia in COPD11 subjects, FEV1
39 pred, PaO2 74 mmHg, exercised at 50 VO2max.
Exercise with 60 oxygen improved SaO2, decreased
lactate, decreased ventilation and reduced
dyspnea at iso-time
Modified from ODonnell D, AJRCCM 1997155530
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Effect of oxygen in 10 non-hypoxemic patients
with severe COPD, during constant work-endurance
time increases with increasing inspired oxygen
Modified from Somfay A, ERJ 20011877
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Medical volume reduction with oxygen
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Ambulatory oxygen therapy

• LTOT is life saving if resting hypoxemia is
  present
• Oxygen acutely reduces dyspnea and improves
  exercise in transient exercise hypoxemia, by
  reducing ventilation and therefore hyperinflation
• Equivocal evidence that training with oxygen adds
  exercise or quality of life benefit over training
  on room air
• Insufficient clinical evidence to support the
  widespread addition of ambulatory systems
• Time for international studies to standardize
  indications for ambulatory LTOT

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Summary of randomized trials of nocturnal oxygen
therapy
Slide courtesy of Dr. Yves Lacasse
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Conclusion

• LTOT is life saving for those with resting
  hypoxaemia
• Ambulatory oxygen should increase mobility for
  those who require LTOT, but the evidence to
  support this is incomplete
• Oxygen for exercise training reduces ventilation
  and may enable training at a higher load
• The cost benefit of ambulatory oxygen in the
  community remains to be evaluated
• Nocturnal oxygen therapy for transient
  desaturation has yet to be shown to result in
  meaningful physiological or clinical improvements