From the Guidelines
An open face mask would be used over a simple face mask when a patient requires a more precise oxygen concentration or when the patient cannot tolerate a closed system. Open face masks deliver oxygen through ports while allowing room air to mix in, making them suitable for patients who feel claustrophobic with traditional masks or who need to communicate more easily. They're particularly beneficial for patients with mild to moderate hypoxemia requiring low to medium oxygen concentrations (typically 24-40%) 1. Simple face masks, in contrast, provide higher oxygen concentrations (40-60%) but create a more enclosed environment.
Key Considerations
- Open face masks are preferred for patients who need frequent nebulizer treatments or oral medication administration without removing their oxygen source.
- They may be better for patients with facial trauma, burns, or those who are at risk of aspiration, as they allow for easier observation and access to the face.
- The choice between these masks ultimately depends on the patient's specific clinical needs, comfort level, and required oxygen concentration 1.
Clinical Guidelines
- According to the BTS guideline for oxygen use in adults in healthcare and emergency settings, simple face masks are suitable for patients with respiratory failure without hypercapnia (type 1 respiratory failure) but are not suitable for patients with hypercapnic (type 2) respiratory failure 1.
- The guideline also recommends starting treatment with a reservoir mask at 15 L/min for acutely breathless patients not at risk of hypercapnic respiratory failure who have saturations below 85%, and adjusting the oxygen concentration downwards as needed 1.
From the Research
Oxygen Delivery Devices
The choice of oxygen delivery device depends on the patient's specific needs and the desired fraction of inspired oxygen (FiO2).
- A simple face mask is often used for patients who require a low to moderate level of supplemental oxygen 2.
- An open face mask, on the other hand, may be used in certain situations where a higher FiO2 is required, but the evidence is limited 3.
Comparison of Oxygen Masks
A study comparing the FiO2 delivery of different oxygen masks found that:
- The measured FiO2 range for an open face mask was 0.30-0.60 3.
- The simple face mask delivered a higher FiO2 range of 0.55-0.73 3.
- The non-rebreather mask delivered the highest FiO2 range of 0.93-1.00 3.
Clinical Applications
In clinical practice, the choice of oxygen delivery device depends on the patient's condition and the desired outcome.
- For patients with acute hypoxemic respiratory failure, high-flow nasal oxygen (HFNC) may be used as a first-line noninvasive respiratory support 4.
- However, the use of an open face mask or other conventional masks may not be suitable for all patients, and the choice of device should be individualized based on the patient's specific needs 3.