The
nasal cannula is a device used to deliver supplemental
oxygenOxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
or airflow to a patient or person in need of respiratory help. This device consists of a plastic tube which fits behind the ears, and a set of two prongs which are placed in the
nostrilA nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation...
s. Oxygen flows from these prongs. The nasal cannula is connected to an oxygen tank, a portable oxygen generator, or a wall connection in a hospital via a flowmeter. The nasal cannula carries 1–6 litres of oxygen per minute. There are also infant or neonatal nasal cannulas which carry less than one litre per minute; these also have smaller prongs. The oxygen fraction provided to the patient ranges roughly from 24% to 35%, or the cannula may merely supply
humidified air- Basics :Respiratory gas humidification is a method of artificial warming and humidifying of respiratory gas for the patient during mechanical ventilation. By the term respiratory gas conditioning, also the cleaning of respiratory gas is understood in addition to warming and humidification...
.
The nasal cannula was invented by Wilfred Jones and patented in 1949 by his employer,
BOCThe BOC Group plc was the official name of the multinational industrial gas and British based company more commonly known as BOC, and now a part of The Linde Group. In September 2004, BOC had over 30,000 employees on six continents, with sales of over £4.6 billion. BOC was a constituent of the...
.
Supplemental oxygen
A nasal cannula is generally used wherever small amounts of supplemental oxygen are required, without rigid control of respiration, such as in oxygen therapy. Most cannulas can only provide oxygen at low flow rates—up to 6 litres per minute (L/min)—delivering an oxygen concentration of 28–44%. Rates above 6 L/min can result in discomfort to the patient, drying of the nasal passages, and possibly nose bleeds (epistaxis).
The nasal cannula is often used in elderly patients or patients who can benefit from oxygen therapy but do not require it to self respirate. These patients do not need oxygen to the degree of wearing a non-rebreather mask. It is especially useful in those patients where vasoconstriction could negatively impact their condition, such as those suffering from strokes.
It may also be used by pilots and passengers in small, unpressurized aircraft that do not exceed certain altitudes. The cannula provides extra oxygen to compensate for the lower oxygen content available for breathing at the low ambient air pressures of high altitude, preventing hypoxia. Special aviation cannula systems are manufactured for this purpose.
Nasal High Flow Therapy
High flows of an air/oxygen blend can be administered via a nasal cannula to accurately deliver high volume of oxygen therapy.
Respiratory gas humidification- Basics :Respiratory gas humidification is a method of artificial warming and humidifying of respiratory gas for the patient during mechanical ventilation. By the term respiratory gas conditioning, also the cleaning of respiratory gas is understood in addition to warming and humidification...
allows the high flows to be delivered comfortably via the cannula. Nasal
high flow therapyHumidified high flow nasal airway respiratory support is a method of delivering a high minute volume of respiratory gas via nasal cannula. The respiratory gas is heated to near body temperature and humidified, usually to saturation vapor pressure. This form of respiratory support is generally...
can be used as an alternative to face mask oxygen and allows the patient to continue to talk, eat and drink while receiving the therapy.
See also
- Oxygen therapy
Oxygen therapy is the administration of oxygen as a medical intervention, which can be for a variety of purposes in both chronic and acute patient care...
- Oxygen mask
An oxygen mask provides a method to transfer breathing oxygen gas from a storage tank to the lungs. Oxygen masks may cover the nose and mouth or the entire face...
- Hyperbaric oxygen therapy
Hyperbaric medicine, also known as hyperbaric oxygen therapy , is the medical use of oxygen at a level higher than atmospheric pressure. The equipment required consists of a pressure chamber, which may be of rigid or flexible construction, and a means of delivering 100% oxygen...
- Space suit
A space suit is a garment worn to keep an astronaut alive in the harsh environment of outer space. Space suits are often worn inside spacecraft as a safety precaution in case of loss of cabin pressure, and are necessary for extra-vehicular activity , work done outside spacecraft...
- Oxygen tent
thumb|300pxAn oxygen tent consists of a canopy placed over the head and shoulders or over the entire body of a patient to provide oxygen at a higher level than normal.Oxygen tents are also used by athletes-see altitude tents.-External links:*...
- Oxygen bar
An oxygen bar is an establishment, or part of one, that sells oxygen for recreational use. Individual flavored scents may be added to enhance the experience...
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