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Cannula
 
 
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A cannula (from Latin "little reed"; plural cannulae) or canula is a tube which can be inserted into the body, often for the delivery or removal of fluid.

Decannulation is the permanent removal of a cannula (extubation
Intubation

In medicine, intubation refers to the placement of a tube into an external or internal orifice of the body. Although the term can refer to endoscopy procedures, it is most often used to denote tracheal intubation....
), especially of a tracheostomy cannula.

Medicine
Cannulae normally come with a trocar
Trocar

A trocar is a hollow cylinder with a sharply pointed end, often three-sided, that is used to introduce cannulas and other similar implements into blood vessels or body cavities....
 attached which allows puncturing of the body to get into the intended space.






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A cannula (from Latin "little reed"; plural cannulae) or canula is a tube which can be inserted into the body, often for the delivery or removal of fluid.

Decannulation is the permanent removal of a cannula (extubation
Intubation

In medicine, intubation refers to the placement of a tube into an external or internal orifice of the body. Although the term can refer to endoscopy procedures, it is most often used to denote tracheal intubation....
), especially of a tracheostomy cannula.

Medicine


Cannulae normally come with a trocar
Trocar

A trocar is a hollow cylinder with a sharply pointed end, often three-sided, that is used to introduce cannulas and other similar implements into blood vessels or body cavities....
 attached which allows puncturing of the body to get into the intended space. There are however 11 different kinds of cannulae: Bias Grind, Vet Point, Lancet Point, Deflected point (Anti-Coring), Pencil Point, Closed End Consistent Wall, Welded "Ball" End, Bullet Point, Razor Edge, Probe Point (Blunt End), and Trocar. Intravenous cannulae are the most common in hospital use. A variety of cannulae are used to establish cardiopulmonary bypass in cardiac surgery
Cardiac surgery

Cardiac surgery is surgery on the heart and/or great vessels performed by a cardiac surgeon. Frequently, it is done to treat complications of ischemic heart disease , correct congenital heart disease, or treat valvular heart disease created by various causes including endocarditis....
. Nasal cannula
Nasal cannula

The nasal cannula is a device used to deliver supplemental oxygen to a patient or person in need of extra oxygen. This device consists of a plastic tube which fits behind the ears, and a set of two prongs which are placed in the nostrils....
 is a piece of plastic tubing which runs under the nose and is used to administer oxygen.

IV cannulation

A venous
Intravenous therapy

File:Infuuszakjes.jpgIntravenous therapy or IV therapy is the giving of liquid substances directly into a vein. It can be intermittent or continuous; continuous administration is called an intravenous drip....
 cannula is inserted into a vein, primarily for the administration of intravenous fluids, obtaining blood samples and administering medicines. An arterial cannula is inserted into an artery, commonly the radial artery, and is used during major operations and in critical care areas to measure beat-to-beat blood pressure and to draw repeated blood samples.

Complications may arise in the vein as a result of the cannulation procedure, the 4 main groups of complication are:
  • hematoma
    Hematoma

    A hematoma, or haematoma, is a collection of blood outside the blood vessels, generally the result of hemorrhage, or more specifically, internal bleeding....
    : a collection of blood, which can result from failure to puncture the vein when the cannula is inserted or when the cannula is removed. Selection of an appropriate vein and gently applying pressure slightly above the insertion point on removal of the cannula may prevent this.
  • infiltration
    Infiltration (medical)

    Infiltration is the diffusion or accumulation of substances not normal to it or in amounts in excess of the normal. The material collected in those tissues or cells is also called infiltration....
    : when infusate enters the subcutaneous tissue instead of the vein. To prevent this a cannula with accurate trim distances may be used. It is essential to fix the cannula in place firmly.
  • embolism
    Embolism

    In medicine, an embolism occurs when an object migrates from one part of the body and causes a blockage of a blood vessel in another part of the body....
    : this can be caused by air, a thrombus, or fragment of a catheter breaking off and entering the venous system. Such things can go on to lodge in an artery, blocking circulation to the corresponding area. Air emboli can be avoided making sure that there is no air in the system. A thromboembolism can be avoided by using a smaller cannula.
  • phlebitis
    Phlebitis

    Phlebitis Phlebitis is an inflammation of a vein, usually in the legs.When phlebitis is associated with the formation of blood clots , usually in the deep veins of the legs, the condition is called thrombophlebitis....
    : an inflammation of the vein resulting from mechanical or chemical irritation or from an infection. Phlebitis can be avoided by carefully choosing the site for cannulation and by checking the type of infusate used.


Nasal cannulation and oral–nasal cannulation

A nasal cannula
Nasal cannula

The nasal cannula is a device used to deliver supplemental oxygen to a patient or person in need of extra oxygen. This device consists of a plastic tube which fits behind the ears, and a set of two prongs which are placed in the nostrils....
 or an oral–nasal cannula consists of a flexible tube, usually with multiple short, open-ended branches for comfortable insertion into the nostril
Nostril

A 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 and/or mouth
Mouth

The mouth, buccal cavity, or oral cavity is the first portion of the alimentary canal that receives food and begins digestion by mechanically breaking up the solid food particles into smaller pieces and mixing them with saliva....
, and may be used for the delivery of a gas (such as pure oxygen
Oxygen

Oxygen no O2 produced; 2) O2 produced, but absorbed in oceans & seabed rock; 3) O2 starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer; 4-5) O2 sinks filled and the gas accumulates]]...
), a gas mixture (as, for example, during anesthesia
Anesthesia

Anesthesia, or anaesthesia , has traditionally meant the condition of having sensation blocked or temporarily taken away. This allows patients to undergo surgery and other procedures without the distress and pain they would otherwise experience....
), or to measure airflow into and out of the nose and/or mouth.

Veterinary use

A cannula is also used in an emergency procedure to relieve pressure and bloat
Bloat

Bloat is a medical condition in which the stomach becomes overstretched by excessive gas content. It is also commonly referred to as torsion, gastric torsion, and gastric dilatation-volvulus when the stomach is also twisted....
ing in cattle due most commonly to their accidentally grazing wilted legume
Legume

A legume is a plant in the family Fabaceae , or a fruit of these specific plants. A legume fruit is a Fruit#Simple fruit that develops from a simple carpel and usually Dehiscence on two sides....
 or legume-dominant pastures, particularly alfalfa
Alfalfa

Alfalfa is a flowering plant in the pea family Fabaceae cultivated as an important forage crop. In the United Kingdom, Australia and New Zealand it is known as lucerne and as lucerne grass in south Asia....
, ladino
Ladino

Ladino may refer to:*Ladino - Sephardic language, the Judaeo-Spanish primarily spoken among Sephardic Jews, or for the written form used in religious texts and translations...
, and red and white clover
Clover

Clover , or trefoil, is a genus of about 300 species of plants in the pea family Fabaceae. The genus has a cosmopolitan distribution; the highest diversity is found in the temperate Northern Hemisphere, but many species also occur in South America and Africa, including at high altitudes on mountains in the tropics....
.

They are also a component used in the insertion of the Verichip
VeriChip

VeriChip is the first Food and Drug Administration -approved human-implantable radio-frequency identification microchip. It is marketed by VeriChip Corporation, a subsidiary of Applied Digital Solutions, and it received United States FDA approval in 2004....
.

Body piercing

Cannulae are used in body piercing
Body piercing

Body piercing is the practice of puncturing or cutting a part of the human body, creating an opening in which body piercing jewelry may be worn....
 when using a standard IV needle (usually between 18GA and 12GA, although may be as large as 0GA, in which case the procedure is known as dermal punching and uses a biopsy punch without a cannula), and for inserting hooks for suspensions
Suspension (body modification)

A suspension is the act of suspending a human body from hooks that have been put through body piercings. These piercings are temporary and are performed just prior to the actual suspension....
.

During piercing, the fistula
Fistula

In medicine, a fistula is an abnormal connection or passageway between two epithelium-lined organs or vessels that normally do not connect....
 is created by inserting the needle. The needle is then removed, leaving the cannula in place, which is sometimes trimmed down. The cannula is then removed and sterile jewellery is inserted into the fistula simultaneously, in order to minimise trauma to the fresh fistula caused by insertion of blunt-ended jewellery.

Non-medical use

In biological research, a push-pull cannula, which both withdraws and injects fluid, can be used to determine the effect of a certain chemical on a specific cell
Cell (biology)

The cell is the structural and functional unit of all known Life organisms. It is the smallest unit of an organism that is classified as living, and is often called the building bricks of life....
. The push part of the cannula is filled with a physiological solution plus the chemical of interest and is then injected slowly into the local cellular environment of a cell. The pull cannula then draws liquid from the extracellular medium, thus measuring the cellular response to the chemical of interest. This technique is especially used for neuroscience
Neuroscience

Neuroscience is a field devoted to the scientific study of the nervous system. The Society for Neuroscience was founded in 1969, but the study of the brain started a long time ago....
.

In general aviation, a cannula refers to a piece of plastic tubing which runs under the nose and is used to administer oxygen in non-pressurized aircraft flying above 10,000 feet above sea level in Canada and above 12,500 feet above sea level in the United States.

See also

  • Hypodermic needle
    Hypodermic needle

    A hypodermic needle is a hollow needle commonly used with a syringe to Injection substances into the body. They may also be used to take liquid samples from the body, for example taking blood from a vein in venipuncture....