The nasal cannula is a device that delivers oxygen or increased airflow to a patient need of respiratory help. It consists of a lightweight tube, which on one end splits into two prongs. Meanwhile the other end of the tube is connected to an oxygen supply, such as a portable oxygen generator, or a wall connection in a hospital via a flowmeter. The cannula is generally attached to the patient by way of the tube hooking around the patient’s ears, or by elastic head band.
The earliest, and most widely used form of adult nasal cannula carries 1–3 litres of oxygen per minute. While cannula with smaller prongs intended for infant or neonatal use can carry less than one litre per minute. As a typical value, flow rates of up to 60 litres of air/oxygen per minute can be delivered through wider bore humidified nasal cannula.
There are two major types of nasal cannula, accourding ot the production process: standard nasal cannula and soft tip nasal cannula. Thanks to dip molding process, the soft tip is more transparent and comfortable use, thus it is always used for child and infant.
Besides, there are some special purpose nasal tubing for different application, like CO2/O2 nasal cannula and gas sampling tubing.