Oxygen therapy in chronic respiratory failure due to COPD

Assessment for long-term oxygen therapy should be undertaken by a specialist respiratory physician.

For best results oxygen therapy should be given for at least 15 hours a day at a flow rate sufficient to maintain the arterial oxygen tension above 8KPa (1,2)

• long-term administration of oxygen (> 15 hours per day) to patients with chronic respiratory failure has been shown to increase survival in patients with severe chronic resting arterial hypoxemia.
• long-term oxygen therapy does not lengthen time to death or first hospitalization or provide sustained benefit for any of the measured outcomes in patients with stable COPD and resting or exercise-induced moderate arterial oxygen desaturation

Breathlessness may be relieved in COPD patients who are either mildly hypoxemic, or non-hypoxemic but do not otherwise qualify for home oxygen therapy, when oxygen is given during exercise training; however, studies have shown no improvement of breathlessness in daily life and no benefit on health related quality of life (3)

An oxygen concentrator is the usual means of supplying long-term, home oxygen therapy.

Evidence for use of long-term oxygen therapy in patients with chronic obstructive pulmonary disease

• patients with stable chronic obstructive pulmonary disease (COPD) and a resting PaO2 <=7.3 kP should be assessed for long-term oxygen therapy(LTOT) which offers survival benefit and improves pulmonary haemodynamics
• LTOT should be ordered for patients with stable COPD with a resting PaO2 <= 8 kPa with evidence of peripheral oedema, polycythaemia (haematocrit>=55%) or pulmonary hypertension
• LTOT should be ordered for patients with resting hypercapnia if they fulfill all other criteria for LTOT

Air travel and use of long-term oxygen therapy in COPD (3)

• is safe for most patients with chronic respiratory failure who are on long-term oxygen therapy
• patients should ideally maintain an in-flight PaO2 of at least 6.7 kPa (50 mmHg)
  • studies indicate that this can be achieved in those with moderate to severe hypoxemia at sea level by supplementary oxygen at 3 liters/min by nasal cannula or 31% by Venturi facemask
  • those with a resting oxygen saturation > 95% and 6-minute walk oxygen saturation > 84% may travel without further assessment, although it is important to emphasize that resting oxygenation at sea level does not exclude the development of severe hypoxemia when traveling by air
  • careful consideration should be given to any comorbidity that may impair oxygen delivery to tissues (e.g., cardiac impairment, anemia). Also, walking along the aisle may profoundly aggravate hypoxemia

For more detailed guidance then see the full BTS guideline.

Reference:

1. Hardinge M, Annandale J, Bourne S, et al.British Thoracic Society guidelines for home oxygen use in adults.Thorax 2015;70:i1-i43.
2. Royal College of Physicians. Domiciliary oxygen therapy services. Clinical guidelines and advice for prescribers. London, Royal College of Physicians, 1999.
3. Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2024. Global strategy for the diagnosis, management, and prevention of chronic obstructive pulmonary disease