From the Guidelines
Supplemented oxygen should be titrated to achieve a target saturation of 88-92% in patients at risk of hypercapnic respiratory failure, with the lowest effective flow rate to maintain this range and prevent life-threatening rebound hypoxaemia. When managing hypercapnia or respiratory acidosis due to excessive oxygen therapy, it is crucial to step down oxygen therapy to the lowest level required to maintain the desired saturation range, which can be achieved using 28% or 24% oxygen from a Venturi mask or 1–2 L/min via nasal cannulae, depending on oxygen saturation and subsequent blood gas measurements 1. Key considerations for supplemented oxygen include:
- Starting with the lowest effective flow rate to achieve target oxygen saturation
- Using delivery methods such as nasal cannula (1-6 L/min), simple face mask (5-10 L/min), non-rebreather mask (10-15 L/min), or high-flow nasal cannula for higher concentrations
- Titration to the lowest flow rate needed to maintain target saturation, typically starting at 1-2 L/min via nasal cannula
- Regular reassessment to adjust flow rates based on the patient's clinical status and oxygen saturation measurements, ensuring satisfactory oxygenation without carbon dioxide retention and/or worsening acidosis 1. In patients with chronic obstructive lung disease, supplemental oxygen should be titrated to improve hypoxemia, with a target saturation of 88 to 92% 1.
From the Research
Supplemented Oxygen Therapy
- Supplemented oxygen therapy is used to treat various respiratory conditions, including chronic obstructive pulmonary disease (COPD) and interstitial lung disease (ILD) 2.
- The American Thoracic Society recommends long-term oxygen use in patients with COPD or ILD with severe chronic resting hypoxemia, and conditional recommendations for ambulatory oxygen use in patients with severe exertional hypoxemia 2.
- In resource-limited settings, low flow nasal oxygen supplementation can be added to non-rebreathing masks as an alternative to high flow nasal cannula oxygenation for acute hypoxemic COVID-19 patients 3.
High-Flow Nasal Cannula (HFNC) Oxygen Therapy
- HFNC oxygen therapy has been shown to be effective in improving oxygenation and reducing the need for escalation of respiratory support in patients with moderate COVID-19 pneumonia 4.
- Compared to standard non-rebreathing masks, HFNC oxygen therapy results in better oxygenation, higher patient satisfaction, and a shorter time for de-escalation of oxygen therapy 4.
- HFNC oxygen therapy has also been shown to be effective in patients with hypostatic pneumonia, resulting in improved oxygenation, reduced dyspnea scores, and lower inflammatory-related parameters 5.
Comparison of Oxygen Therapy Devices
- Studies have compared the effectiveness of HFNC oxygen therapy to standard oxygen face masks in various patient populations, including post-extubation intensive care unit patients 6.
- These studies have consistently shown that HFNC oxygen therapy results in improved oxygenation and reduced need for reintubation compared to standard oxygen face masks 6.
- The use of HFNC oxygen therapy may be more effective than standard oxygen supply devices for oxygenation in certain patient populations, including those with COVID-19 pneumonia and hypostatic pneumonia 4, 5.