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Choking

Choking Overview

Choking is a blockage of the upper airway by food or other objects, which prevents a person from breathing effectively. Choking can cause a simple coughing fit, but complete blockage of the airway may lead to death.

Choking is a true medical emergency that requires fast, appropriate action by anyone available. Emergency medical teams may not arrive in time to save a choking person's life.

  • Breathing is an essential part of life. When we inhale, we breathe in a mix of nitrogen (75%), oxygen (21%), carbon dioxide, and other gases (4%).
    • In the lungs, oxygen enters the bloodstream to travel to the rest of the body. Our bodies use oxygen as a fuel source to make energy from the food we eat. Carbon dioxide, a waste product, enters the bloodstream and travels back to the lungs.
    • When we exhale, we breathe out carbon dioxide (8%), nitrogen (71%), and oxygen (16%).
    • When someone is choking with a completely blocked airway, no oxygen can enter the lungs. The brain is extremely sensitive to this lack of oxygen and begins to die within four to six minutes. It is during this time that first aid must take place. Irreversible brain death occurs in as little as 10 minutes.


Next: Choking Causes »

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Choking

Broken or Knocked-Out Teeth Overview

Each individual tooth is composed of calcium and several other organic components. It is divided into 3 layers: enamel, dentin, and pulp—each layer having a specific role.

  • Enamel is a hard outer protective coating. It is the hardest substance in the body. A similar substance called cementum provides a protective coating over the root. It differs from dentin by virtue of its porous nature.

  • The vast majority of the tooth is composed of dentin, which is found directly beneath the enamel.

  • The pulp, the innermost layer, contains the blood supply that nourishes the tooth as well as nerve fibers that provide pain and temperature sensation. It also produces the dentin.

Anatomically, the tooth is made up of the crown and root. The crown is the visible portion you see inside the mouth. The root extends beneath the gum line. ...

Read the Broken or Knocked-out Teeth article »



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