Trachea emergency situation, and this is a cricothyrotomy. Tracheal agenesis, is a rare birth defect in which the trachea fails to develop. The defect is usually fatal though sometimes surgical intervention has been successful. A tracheoesophageal fistula is a congenital defect in which the trachea and esophagus are abnormally connected. Sometimes as an anatomical variation one or more of the tracheal rings are completely formed. These "O" rings are smaller than the normal C-shaped and can cause narrowing of the trachea resulting in breathing difficulties. An operation called a "slide tracheoplasty" can be performed which opens up the rings and rejoins
Composition of the human body not in an essential biological role. The average adult human body contains approximately atoms and contains at least detectable traces of 60 chemical elements. About 29 of these elements are thought to play an active positive role in life and health in humans. The relative amounts of each element vary by individual, mainly due to differences in the proportion of fat, muscle and bone in their body. Persons with more fat will have a higher proportion of carbon and a lower proportion of most other elements (the proportion of hydrogen will be about the same). The numbers in the table