When to initiate home oxygen therapy?

From the Guidelines

Home oxygen therapy is recommended for patients with chronic hypoxemia, typically defined as a resting arterial oxygen saturation (SpO2) of ≤88% or a partial pressure of arterial oxygen (PaO2) of ≤55 mmHg on room air, as stated in the British Thoracic Society guidelines 1.

Key Considerations

• Patients with SpO2 between 89-93% or PaO2 of 56-59 mmHg may qualify if they have evidence of end-organ damage from hypoxemia, such as cor pulmonale, pulmonary hypertension, or polycythemia.
• The most common conditions requiring home oxygen include chronic obstructive pulmonary disease (COPD), interstitial lung disease, cystic fibrosis, pulmonary hypertension, and congestive heart failure.
• Oxygen should be prescribed at a flow rate sufficient to maintain SpO2 ≥90% or PaO2 ≥60 mmHg, typically starting at 1-2 liters per minute via nasal cannula and titrating as needed, as recommended by the European Respiratory Society task force 1.

Assessment and Follow-up

• Before initiating home oxygen, patients should undergo formal assessment with arterial blood gas analysis or pulse oximetry at rest, during exercise, and sometimes during sleep.
• Patients may require continuous oxygen therapy (≥15 hours daily including during sleep) or oxygen only during exertion or sleep, depending on when hypoxemia occurs.
• The dose should be assessed at least once each year, and the flow should be adjusted according to arterial blood gas tensions or oximetry results, as stated in the British Thoracic Society guidelines 1.

Benefits of Home Oxygen Therapy

• Home oxygen improves survival in hypoxemic COPD patients and can enhance quality of life, exercise capacity, and cognitive function in various conditions by ensuring adequate tissue oxygenation and reducing strain on the cardiovascular system.
• The British Thoracic Society guidelines provide detailed evidence-based guidance for the use of home oxygen for patients out of hospital, including patients with a variety of long-term respiratory illnesses and other groups in whom oxygen is currently ordered 1.

From the Research

Indications for Home Oxygen Therapy

• Patients with chronic obstructive pulmonary disease (COPD) and severe resting hypoxemia are eligible for long-term oxygen therapy (LTOT) at home, as it has been shown to improve survival 2, 3.
• Patients with COPD and moderate chronic resting hypoxemia should not be prescribed LTOT, according to conditional recommendations 3.
• Ambulatory oxygen use is conditionally recommended for patients with COPD or interstitial lung disease (ILD) with severe exertional hypoxemia 3.
• Patients with COPD who are mobile outside the home and require more than 3 L/min of continuous-flow oxygen during exertion may benefit from ambulatory liquid-oxygen use, although the evidence is very low-quality 3.

Assessment and Monitoring

• Oxygen saturation should be monitored at rest, on exercise, and during sleep in COPD patients undergoing pulmonary rehabilitation programs 4.
• Cardiopulmonary exercise testing can be used to select different modes of training modalities in pulmonary rehabilitation 5.

Education and Safety

• Patients and their caregivers should receive education on oxygen equipment and safety, as stated in a best-practice statement 3.
• Healthcare professionals and pulmonary rehabilitation organizations should provide individualized, comprehensive interventions based on thorough assessments of physical, emotional, and social traits in COPD patients 5.