Breathing is a vital function of all living beings. Through her gas changes are made between living tissue and the external environment. In humans, this function is an involuntary act controlled by the medulla. Involved in the process the following parts of the body: the nose, pharynx, larynx, trachea, bronchi and lungs. These are all the respiratory system. From the nose or mouth, air, composed mainly of oxygen, nitrogen and water vapor, passes through the pharynx and larynx and reaches the trachea (inspiration phase), then passes through the bronchi and the pulmonary alveoli , which are surrounded by tiny blood vessels, capillaries, where it carries out gas exchange: Sign oxygen in the blood and it releases carbon dioxide that enters the alveoli, runs contrary and comes out (phase exhalation).
The set of operations performed to restore normal breathing. These maneuvers will include rescue breathing, alternative pressure of the back and arms raised, in addition to the use of mechanical respirators.
Respiratory movements are controlled by the medulla. This slows down the breathing, if the body has excess oxygen, or accelerate, if blood is plentiful carbon dioxide.