Anatomy & Organs

Trachea – structure, function & diseases


As the first section of the lower airways, the trachea is the air-conducting link between the larynx and the bronchi . Air reaches the lungs through the trachea . If food gets into the trachea instead of the esophagus due to hasty eating, this causes a strong urge to cough which is accompanied by a spasm of the trachea muscles and is probably familiar to most people.

What is the trachea?

The trachea connects to the larynx and ends at the level of the breastbone, so it extends from the neck to the chest.

Typically, the trachea is between 10 and 15 cm long and about 15 to 25 mm in diameter. The elastic wall of the windpipe, also called the trachea, is made up of connective tissue and layers of smooth muscle.

Cartilage braces in the front wall ensure the stability and strength of the trachea.

Anatomy & Structure

The muscular tube of the trachea divides into the right and left main bronchus at the level of the 4-5 thoracic vertebrae, at the upper end it connects to the cricoid cartilage of the larynx.At the branch, the tracheal fork, there is a spur, the so-called carina trachea, which is important in the distribution of air to the right and left main bronchus. The trachea lies in front of the esophagus and behind the thyroid . It owes its strength to the 16-20 cartilage braces in the front wall, which are connected to one another by annular ligaments.

The elastic tissue between the cartilage braces is important to allow the trachea tube to stretch and shift when swallowing or moving the head. While the cartilage braces with the ligaments are on the front, smooth muscles and connective tissue are on the back.

The tracheal muscles can narrow the trachea by up to 25% of its original diameter. The inner wall of the trachea is lined with a ciliated epithelium. Through the ciliated epithelium and the mucus produced by the goblet cells, foreign bodies such as dust can be transported out of the trachea and coughed up or swallowed.

Functions & Tasks

The main function of the trachea is gas transport, i.e. the conduction of air from the throat area to the lungs. In addition, the air in the trachea is heated, moistened and freed from foreign bodies with the help of the ciliated epithelium.

The inner wall of the trachea is densely covered with ciliated hairs and goblet cells, which secrete mucus. The cilia move the dust particles bound in the mucus and other foreign bodies towards the throat. If an inhaled foreign body is too large to be transported out of the trachea in this way, a strong cough reflex sets in. This causes the foreign body to be coughed up.

The cartilage braces that enclose the front of the trachea have a stabilizing function. When inhaling, a negative pressure is created, which would cause the elastic trachea to collapse without stabilizing elements. The cartilage braces ensure that you can breathe in without the trachea closing or collapsing due to the negative pressure.

The elasticity of the trachea is particularly important. During the swallowing process, the larynx moves up regularly and the trachea must be able to follow this movement without any problems. If the cough reflex sets in, the trachea is required to be even more elastic, as it also has to stretch in the longitudinal direction. The inside of the trachea is a mucous membrane under which there are tracheal glands for additional moistening, which, like the goblet cells, also produce mucus.


There can be a variety of problems related to the trachea . The aspiration of a foreign body, which triggers a strong urge to cough , is particularly common. If an inhaled foreign body cannot be coughed up, there is a risk of suffocation and emergency measures such as a tracheotomy are necessary.The most common disease related to the trachea is the so-called trancheitis, an inflammation of the trachea . This can be caused by an infection with bacteria or viruses , but it can also occur due to an allergy and causes pain when swallowing and coughing up phlegm . With a tracheal stenosis, the trachea is narrowed, which can lead to shortness of breath and can be detected by altered breathing sounds , such as whistling or buzzing.

Accidental injuries to the trachea often require surgical treatment. In tracheomalacia , the trachea collapses during inspiration because the cartilage braces do not adequately support the trachea. Symptoms of tracheomalacia include difficulty breathing , hoarseness , and abnormal breath sounds.

Typical & common diseases

Lisa Newlon
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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.