When does a patient require home oxygen therapy?

Home Oxygen Therapy Indications

Home oxygen therapy should be prescribed for patients with specific clinical conditions who demonstrate resting hypoxemia, with PaO2 ≤7.3 kPa (≤55 mmHg) or PaO2 ≤8 kPa (≤60 mmHg) with evidence of end-organ damage. 1

Long-Term Oxygen Therapy (LTOT) Indications by Condition

COPD

• LTOT should be ordered for patients with stable COPD with resting PaO2 ≤7.3 kPa (≤55 mmHg) 1
• LTOT should be ordered for COPD patients with PaO2 ≤8 kPa (≤60 mmHg) if there is evidence of:
  • Peripheral edema
  • Polycythemia (hematocrit ≥55%)
  • Pulmonary hypertension 1
• Patients with COPD and resting hypercapnia can receive LTOT if they meet other criteria 1

Interstitial Lung Disease (ILD)

• LTOT should be ordered for ILD patients with resting PaO2 ≤7.3 kPa (≤55 mmHg) 1
• LTOT should be ordered for ILD patients with resting PaO2 ≤8 kPa (≤60 mmHg) with peripheral edema, polycythemia, or pulmonary hypertension 1
• Palliative oxygen may be considered for ILD patients with severe breathlessness 1

Cystic Fibrosis

• LTOT should be ordered for CF patients with resting PaO2 ≤7.3 kPa (≤55 mmHg) 1
• LTOT should be ordered for CF patients with resting PaO2 ≤8 kPa (≤60 mmHg) with peripheral edema, polycythemia, or pulmonary hypertension 1

Pulmonary Hypertension

• LTOT should be ordered for patients with pulmonary hypertension when PaO2 is ≤8 kPa (≤60 mmHg) 1

Advanced Cardiac Failure

• LTOT should be ordered for patients with advanced cardiac failure with resting PaO2 ≤7.3 kPa (≤55 mmHg) 1
• LTOT should be ordered for patients with advanced cardiac failure with resting PaO2 ≤8 kPa (≤60 mmHg) with peripheral edema, polycythemia, or pulmonary hypertension on ECG or echocardiograph 1

Neuromuscular or Chest Wall Disorders

• Non-invasive ventilation (NIV) should be first-line treatment for patients with chest wall or neuromuscular disease causing type 2 respiratory failure 1
• Additional LTOT may be required for hypoxemia not corrected with NIV 1

Assessment Process for LTOT

Initial Screening and Referral

• Patients with resting stable SpO2 ≤92% should be referred for blood gas assessment to evaluate LTOT eligibility 1
• In patients with peripheral edema, polycythemia, or pulmonary hypertension, referral may be considered at SpO2 levels ≤94% 1

Blood Gas Assessment

• Initial assessment for LTOT requires arterial blood gas (ABG) sampling 1
• Two ABG measurements at least 3 weeks apart during clinical stability are required to confirm LTOT need 1
• Capillary blood gases (CBG) can be used for oxygen titration after initial ABG assessment 1

Timing of Assessment

• Formal LTOT assessment should occur after a period of stability of at least 8 weeks from the last exacerbation 1
• Patients should not normally have LTOT ordered during an acute exacerbation 1
• If oxygen is ordered at hospital discharge, it should be limited to patients with SpO2 ≤92% who are breathless and unable to manage without oxygen 1

Special Considerations

Smoking and LTOT

• If LTOT is ordered for patients who continue to smoke, they should be informed of potentially limited clinical benefit 1
• Smoking cessation should be strongly encouraged due to increased fire risk and reduced therapeutic benefit 1

Discontinuation of Oxygen Therapy

• Oxygen therapy can be discontinued once a patient is clinically stable and maintains target saturation on room air 1
• Most stable patients will be stepped down to 2 L/min via nasal cannulae prior to cessation 1
• Patients at risk of hypercapnic respiratory failure may be stepped down to 1 L/min or 24% Venturi mask 1
• Oxygen saturation should be monitored for 5 minutes after stopping oxygen therapy and rechecked at 1 hour 1

Delivery Devices

• Nasal cannulae should be the first choice of delivery device for patients requiring home oxygen therapy 1, 2
• Venturi masks should be considered for patients at risk of hypercapnic respiratory failure or with cognitive problems 1
• Oxygen concentrators should be used to deliver LTOT at flow rates of 4 L/min or less 1

Palliative and Short-Burst Oxygen Therapy

Palliative Oxygen Therapy (POT)

• POT should not be provided for non-hypoxemic patients (SpO2 ≥92%) with cancer or end-stage cardiorespiratory disease 1
• For intractable breathlessness, assessment for opiates and non-pharmacological treatments should be prioritized 1
• POT may be considered by specialist teams for intractable breathlessness unresponsive to all other treatments 1

Short-Burst Oxygen Therapy (SBOT)

• SBOT should not be ordered for use before or after exercise in hypoxemic or normoxic COPD patients 1
• SBOT should not be ordered on discharge for non-hypoxemic patients with severe COPD 1
• SBOT with high flow oxygen (12 L/min via non-rebreather mask) should be offered for acute cluster headache attacks 1

Safety Considerations

• Risk assessments should be conducted before home oxygen installation and every 6 months thereafter 1
• Cylinders should be secured properly when transported in vehicles 1
• Patients should be educated about fire risks and avoiding naked flames near oxygen 1, 2

Home oxygen therapy, when properly prescribed according to these guidelines, can improve survival in patients with chronic respiratory failure 3, 4 and enhance quality of life in appropriately selected patients 5.