Non-rebreather Mask
The non-rebreather mask (also called reservoir mask) is the best option for high concentrations of oxygen.
Oxygen flows into the bag which is connected to the mask with a one-way valve. The mask has one or more one-way valves to allow exhaled air to escape.
Because of these valves gas can only move in one direction and exhaled air does not mix with the inhaled oxygen.
A variation of this mask called a partial rebreather mask has a two-way valve in the mask that allows some mixing of air and oxygen. Double check the mask you are using.
Flow rate: 10 - 15L/min (less than 10L/min will not inflate the bag and cause CO2 rebreathing)
FiO2: 60 - 90%
Advantages
- Can deliver much higher oxygen concentrations
Disadvantages
- Should only be used short term
- Variable FiO2 due to influence of the respiratory rate and mask fit
