What is the Trachea?

What is the Structure of the Trachea and Why is it Important in Disease?

diagram showing chest anatomy
What is the trachea?. A.D.A.M. Medical Encyclopedia

Definition: Trachea

The trachea is the large air tube that leads from the larynx (the voice box) to the bronchi (the large airways at the top of the lungs).

Structure of the Trachea

The trachea is made up of rings of cartilage, and is roughly 4 inches long and 1 inch in diameter.

Function of the Trachea

The trachea serves as a passageway to allow passage of air from the region of the voice box to the main respiratory channels (bronchi) which enter the lungs.

Medical Conditions Involving the Trachea

The trachea can be involved medically in a number of conditions. Some of these include:

  • Tracheitis - Tracheitis is an infection of the trachea most commonly caused by the bacteria staphylococcus aureus. It is most common in young children and can make breathing difficult.
  • Tracheal foreign body - This occurs when a foreign body is breathed in (aspirated) through the mouth and become lodged in the trachea. It is most common in young children, but may also occur in the elderly, or those who have a decreased level of consciousness for any reason.
  • Tracheal cancer - Cancer of the trachea is very rare. These cancers are most often squamous cell carcinomas and are often related to smoking.
  • Tracheoesophageal fistula - Rarely, an abnormal passageway called a fistula may develop between the trachea and esophagus. When this occurs, food that is passing through the esophagus may enter the trachea, and subsequently the lungs. This may occur when a cancer is present, especially cancer of the esophagus which erodes the walls of the trachea allowing this abnormal passageway to develop. In children, a tracheoesophageal fistula may develop along with incomplete formation of the esophagus (esophageal atresia.) Roughly 1 in 4,000 children are born with this abnormality. Thankfully, this is now very treatable with the help of a skilled pediatric surgical team.
  • Tracheal stenosis - When the trachea is damaged, scarring may develop and the trachea may become narrowed.
  • Tracheobronchomalacia - Tracheobronchomalacia is an uncommon condition in which the trachea collapses on itself during breathing and with coughing. It occurs most often as a complication of chronic obstructive pulmonary disease (COPD) and may also occur as a complication of endotracheal intubation—usually long-term intubation. In children, it may be present from birth as a syndrome with other abnormalities.

    Procedures to Evaluate the Trachea

    • Tracheal dilation - When the trachea becomes narrowed due to scarring and inflammation, instruments may be placed that dilate the trachea.
    • Endotracheal intubation - When a patient is unable to breathe on her own, as during general surgery, an endotracheal tube may be placed through the mouth and into the trachea. This tube is then connected to a mechanical ventilator to allow for breathing to occur.
    • Tracheostomy - A tracheostomy is a surgical procedure in which an endotracheal.tube is inserted directly into the trachea. It is used when intubation through the nose or mouth with an endotracheal tube is not possible, or when long-term ventilator support is needed (such as when a person experiences prolonged unconsciousness and coma.) Some other conditions for which a tracheostomy may be used include tumors causing obstruction of the windpipe, epiglottitis, trauma with a chest wall injury, or spinal cord injury. In addition to providing access for ventilation, a tracheostomy can be used to remove secretions from the airways. 

      Also Known As: windpipe

      Examples: Joe's cough had been worsening over the past few weeks, and his oncologist discovered that his lung cancer had spread to his trachea.

      Sources:

      Memorial Sloan-Kettering Cancer Center. Tracheal Dilation. Accessed 05/26/16. https://www.mskcc.org/cancer-care/types/tracheal-diseases/diagnosis-treatment-msk/treatment-tracheal-stenosis

      National Cancer Institute. SEER Training Module. Larynx and Trachea. Accessed 12/30/15. https://training.seer.cancer.gov/anatomy/respiratory/passages/larynx.html

      Seattle Children’s Hospital. Tracheoesophageal fistula and esophageal atresia. Accessed 05/26/16. http://www.seattlechildrens.org/medical-conditions/chromosomal-genetic-conditions/tef-and-ea/

      U.S. Library of Medicine. MedlinePlus. Tracheitis. Updated 11/25/14. https://medlineplus.gov/ency/article/000988.htm

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