Ventilation–perfusion coupling

From WikiMD's Wellness Encyclopedia

Alveolus diagram.svg

Ventilation–perfusion coupling

Ventilation–perfusion coupling is a physiological process that describes the matching of ventilation (airflow) to perfusion (blood flow) in the lungs. This process is essential for efficient gas exchange in the alveoli of the lungs.

Physiology[edit | edit source]

In the lungs, ventilation refers to the movement of air into and out of the alveoli, while perfusion refers to the blood flow in the pulmonary capillaries surrounding the alveoli. Ventilation–perfusion coupling ensures that well-ventilated areas of the lungs receive adequate blood flow and vice versa, optimizing gas exchange.

The main mechanism behind ventilation–perfusion coupling is the regulation of pulmonary arteriole diameter in response to local oxygen levels. In well-ventilated areas with high oxygen levels, pulmonary arterioles dilate, increasing blood flow to match ventilation. Conversely, in poorly ventilated areas with low oxygen levels, pulmonary arterioles constrict, diverting blood flow to better-ventilated regions.

Clinical Significance[edit | edit source]

Imbalances in ventilation–perfusion coupling can lead to impaired gas exchange and hypoxemia (low blood oxygen levels). Conditions such as pulmonary embolism, pneumonia, and chronic obstructive pulmonary disease (COPD) can disrupt the matching of ventilation and perfusion, resulting in ventilation–perfusion mismatch.

Assessment of ventilation–perfusion coupling is crucial in diagnosing and managing respiratory disorders. Techniques such as ventilation–perfusion scans and arterial blood gas analysis can help evaluate the efficiency of gas exchange in the lungs.

See also[edit | edit source]




WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD