Airway obstruction
Airway obstruction is a respiratory
Respiration (physiology)
'In physiology, respiration is defined as the transport of oxygen from the outside air to the cells within tissues, and the transport of carbon dioxide in the opposite direction...

 problem caused by increased resistance in the bronchiole
The bronchioles or bronchioli are the first airway branches that no longer contain cartilage or glands in their submucosa. They are branches of the bronchi.The bronchioles terminate by entering the circular sacs called alveoli.- Structure :...

s (usually from a decreased radius of the bronchioles) that reduces the amount of air inhaled in each breath and the oxygen
Breathing gas
Breathing gas is a mixture of gaseous chemical elements and compounds used for respiration.Air is the most common and only natural breathing gas...

 that reaches the pulmonary arteries
Pulmonary artery
The pulmonary arteries carry deoxygenated blood from the heart to the lungs. They are the only arteries that carry deoxygenated blood....

. It is different from airway restriction (which prevents air from diffusing into the pulmonary arteries because of some kind of blockage in the lungs).


Obstruction can be measured using spirometry
Spirometry is the most common of the pulmonary function tests , measuring lung function, specifically the measurement of the amount and/or speed of air that can be inhaled and exhaled...

. A decreased FEV1/FVC ratio (versus the normal of about 80%) is indicative of an airway obstruction, as the normal amount of air can no longer be exhaled in the first second of expiration. An airway restriction would not produce a reduced FEV1/FVC ratio, would produce a reduced vital capacity
Vital capacity
Vital capacity is the maximum amount of air a person can expel from the lungs after a maximum inspiration. It is equal to the inspiratory reserve volume plus the tidal volume plus the expiratory reserve volume....

. The ventilation is therefore affected leading to a ventilation perfusion mismatch and hypoxia.

See also

  • Stridor
    Stridor is a high pitched wheezing sound resulting from turbulent air flow in the upper airway. Stridor is a physical sign which is produced by narrow or obstructed airway path. It can be inspiratory, expiratory or biphasic . Inspiratory stridor is common...

  • Recurrent airway obstruction
    Recurrent Airway Obstruction
    Recurrent airway obstruction, also known as broken wind, heaves, or sometimes by the term usually used for humans , is a respiratory disease in horses...

  • Obstructive lung disease
    Obstructive lung disease
    Obstructive lung disease is a category of respiratory disease characterized by airway obstruction. It is generally characterized by inflamed and easily collapsible airways, obstruction to airflow, and frequent office visits and hospitalizations. Types of obstructive lung disease include; Asthma,...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.