Guidelines for Proper Oxygen Device Delivery
The proper oxygen device should be selected based on the patient's clinical condition, target oxygen saturation range, and risk of hypercapnic respiratory failure, with nasal cannulae being the first-choice delivery device for most patients requiring home or hospital oxygen therapy. 1
Oxygen Delivery Principles
- Oxygen is a treatment for hypoxemia, not breathlessness, and should be administered by staff trained in oxygen administration 1
- Oxygen should be prescribed according to a target saturation range, and those administering oxygen therapy should monitor the patient to keep within this target range 1
- For most acutely ill patients without risk of hypercapnic respiratory failure, aim for a target saturation of 94-98% 1
- For patients with COPD or other risk factors for hypercapnic respiratory failure (e.g., morbid obesity, cystic fibrosis, chest wall deformities, neuromuscular disorders), aim for a target saturation of 88-92% 1
Oxygen Delivery Devices
Nasal Cannulae
- Recommended as first-choice delivery device for most patients requiring oxygen therapy 1
- Flow rate should be adjusted between 2-6 L/min for medium-concentration oxygen therapy to achieve desired target saturation 1
- For patients at risk of hypercapnic respiratory failure, use 1-2 L/min 1
- Advantages: more comfortable for patients, less likely to be removed during meals, and cost-effective 1
Simple Face Masks
- Delivers oxygen concentrations of 40-60% at flow rates of 5-10 L/min 2
- Flow rates should never be below 5 L/min due to risk of carbon dioxide rebreathing 1, 2
- Suitable for patients requiring medium-concentration oxygen therapy without risk of hypercapnia 2
Venturi Masks
- Recommended for patients requiring precise control of FiO₂ 1, 2
- Can deliver constant FiO₂ of 24%, 28%, 31%, 35%, 40%, and 60% oxygen 1
- Particularly useful for patients at risk of hypercapnic respiratory failure (24% or 28% Venturi mask) 1
- For patients with COPD with respiratory rate >30 breaths/min, set flow rate above the minimum specified for the Venturi mask 1
High-Concentration Reservoir Masks
- Delivers oxygen concentrations of 60-90% at flow rate of 15 L/min 2
- Preferred method for delivering high-concentration oxygen to critically ill patients until reliable pulse oximetry monitoring is established 1
- Not suitable for patients at risk of hypercapnic respiratory failure 2
Monitoring Oxygen Therapy
- Oxygen saturation should be observed for at least 5 minutes after starting oxygen therapy or after changing concentration 1
- Record oxygen saturation, delivery system, and flow rate on the patient's monitoring chart 1
- Most stable patients should have saturation measured after 1 hour of oxygen therapy and then four-hourly 1
- Patients with signs of critical illness should have oxygen saturation monitored continuously 1
- Pulse oximetry should be available in all locations where emergency oxygen is used 1
- For patients at risk of hypercapnic respiratory failure, arterial or arterialised capillary blood gases should be measured 30-60 minutes after an increase in oxygen therapy 1
Special Considerations
- For perioperative and postoperative care, medium-concentration masks or nasal cannulae are usually sufficient (target 94-98%), except for COPD patients 1
- In emergency departments, consider the risk of hypercapnic respiratory failure when selecting devices 1
- For general and respiratory wards, device selection depends on expected duration of treatment, type of respiratory illness, breathing pattern, need for humidification, risk of CO₂ retention, and patient compliance 1
- Oxygen equilibration typically occurs within 3.5 minutes after initiating oxygen therapy and within 4.5 minutes after discontinuation, allowing for relatively quick assessment of adequacy 3
Practical Implementation
- Ensure all clinicians prescribing oxygen have appropriate training 1
- Every hospital should have a training program to ensure clinical staff are familiar with oxygen administration policies 1
- For home oxygen therapy, ensure patients/caregivers understand safety recommendations including proper storage of cylinders, no smoking near oxygen, and avoiding naked flames 1
- When using pulse oximetry to guide therapy, be aware that readings may be inaccurate in hemodynamic instability, carboxyhemoglobinemia, jaundice, or with dark skin pigmentation 4
- For black patients, a higher SpO₂ target (95%) may be required compared to white patients (92%) to ensure adequate oxygenation 5
By following these guidelines for proper oxygen device delivery, clinicians can optimize patient outcomes while minimizing risks associated with both hypoxemia and hyperoxemia.