The windpipe or trachea is a tube that passes air from the back of the throat to the smaller airways in the lungs called bronchi. It is the tube that connects the nose and mouth to the lungs. It is an important part of the respiratory system because, when an animal or person breathes in, air flows into the lungs through the windpipe. Any damage to it is potentially life-threatening because of its role in respiration.
Tracheal perforation describes a condition that is characterized by loss of integrity of the tracheal wall causing a hole or rip. This hole or rip can be caused by a penetrating trauma, trauma from inside the trachea, or blunt neck or chest trauma. Tracheal perforation allows leakage of air into the surrounding tissues and creates air pockets under the skin, air collection in the mediastinum (in between the lungs), and potentially air in the sac around the heart, free air in the chest cavity, and air in the most posterior part of the abdominal cavity (pneumoretroperitoneum).
The severity of the tracheal wall ranges from a small hole in trachea to a complete tearing away of the trachea (complete tracheal avulsion). When complete tracheal avulsion occurs, the mediastinal tissues can help to maintain the airways.
Common signs and symptoms, noticable immediately after a trauma or a week later, include
Pockets of air collected under the skin
Lack of appetite (anorexia)
Lack of energy
Excessive salivation (ptyalism)
Harsh crowing sound as dog breathes in