Nasal Cannula
The nasal cannula delivers oxygen through two prongs sitting in the nostrils.
Nasal cannulas can also easily fall out and provide a variable FiO2.
Flow rate: 1 - 6L/min.
FiO2 (fraction of inspired oxygen): ~24 - 44% (increasing by about 4% per L/min).
(FiO2 is variable since respiratory rate influences how much room air mixes with oxygen)
Advantages
- Small and lightweight
- Does not obstruct the mouth
Disadvantages
- Can be uncomfortable at higher flow rates (> 4L/min)
- Can dry out nasal mucosa and cause skin damage
- Can fall out
- Variable FiO2 depending on respiratory rate and nasal breathing
