When your body doesn't have enough oxygen, you could get hypoxemia or hypoxia. These are dangerous conditions. Without oxygen, your brain, liver, and other organs can be damaged just minutes after symptoms start.
Hypoxemia (low oxygen in your blood) can cause hypoxia (low oxygen in your tissues) when your blood doesn't carry enough oxygen to your tissues to meet your body's needs. The word hypoxia is sometimes used to describe both problems.
Alveoli: thin-walled, small sacs located at the ends of the smallest airways in the lungs where the exchange of oxygen and carbon dioxide takes place.
Antibiotic: medication used to treat infection caused by bacteria. Antibiotics do not protect against viruses and do not prevent the common cold.
Anticholinergics: (also called cholinergic blockers or "maintenance" bronchodilators). This type of medicine relaxes the muscle bands that tighten around the airways. This action opens the airways, letting more air out of the lungs to improve breathing. Anticholinergics also help clear mucus from the lungs.
Antihistamine: medication that stops the action of histamine, which causes symptoms of allergy such as itching and swelling.
Anti-inflammatory: medication that reduces inflammation (swelling in the airway and mucus production).
Asthma: a disease of the airways or branches of the lung (bronchial tubes) that carry air in and out of the lungs. Asthma causes the airways to narrow, the lining of the airways to swell and the cells that line the airways to produce more mucus. These changes make breathing difficult and cause a feeling of not getting enough air into the lungs. Common symptoms include cough, shortness of breath, wheezing, chest tightness, and excess mucus production.
Beta2-agonists: a bronchodilator medication that opens the airways of the lung by relaxing the muscles around the airways that have tightened (bronchospasm). These medications may be short acting (quick relief) or long acting (control) medications. Short acting beta2 agonists are the drugs used to relieve asthma symptoms when they occur.
Breath sounds: lung sounds heard through a stethoscope.
Breathing rate: the number of breaths per minute.
Bronchial tubes: airways in the lung that branch from the trachea (windpipe).
Bronchioles: the smallest branches of the airways in the lungs. They connect to the alveoli (air sacs).