Difficulties with the system that takes oxygen from the air and passes it on to the bloodstream, subject to a variety of lung and breathing disorders.
Difficulties with normal respiration that may be caused by structural irregularities in the respiratory system, acid-base irregularities, or infections that affect the organs involved in breathing. During normal breathing, air is taken in through the nose and propelled to the back of the throat and the larynx, or voice box. The air passes through the windpipe and enters the bronchi, or airways, which distribute the inhaled air to the air sacs of the lungs, where oxygen and carbon dioxide are exchanged. Any inflammation, abnormality, or obstruction in these structures can inhibit the flow of air and produce breathing problems.