Difference Between Ventilation And Perfusion

Ventilation and perfusion work together in the body to provide oxygen and dispose of carbon dioxide. Ventilation provides tissue and organs oxygen by the process of mechanical inspiration and exhalation of the lungs. This provides the alveoli within the lungs with oxygen, as well as the ability to expel waste products like carbon dioxide. Perfusion provides the tissues and organs with oxygen by the mechanism of diffusion between the pulmonary capillaries and alveoli.

Ventilation Ventilation is the movement of air in and out of the lungs, also known as inspiration and expiration as previously stated. Respirations are controlled by the medulla oblongata in the brain. The medulla oblongata initiates the signal for the respiratory muscles to
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Oxygen is delivered to the alveoli by ventilation, specifically inspiration. As oxygen is removed from the alveoli by diffusing into the pulmonary capillary blood. Carbon dioxide is removed from the alveoli by ventilation, specifically expiration which pushes the carbon dioxide waste out of the lungs into the air. Perfusion however removed carbon dioxide by bringing to the surface of the alveoli as the oxygen is being diffused through the venous blood. Ventilation can be affected by the ability of the respiratory muscles to contract. Whereas, perfusion can be affected by blocking of the alveoli (ex. excess mucous, dirt or disease causing organisms). Ventilation involves the nose, pharynx, larynx, trachea, and the right and left bronchi. Perfusion involves the respiratory bronchioles, alveolar ducts, and the alveoli. Ventilation id dependent on the amount and ability of air (oxygen and carbon dioxide) inspired into the lungs. Perfusion is dependent on the output of blood from the right ventricle that flows through the pulmonary …show more content…
This occurs when there is excess fluid in the plural cavity. The plural cavity is the thin, fluid filled space that surrounds the lungs and prevents friction rub and cushion. One of the main causes of pleural effusion is congestive heart failure. This occurs as a result of an increase in pulmonary capillary pressure, which in turn increased the interstitial fluid in the lung. Most often the heart failure that causes pleural effusions are related to right side heart failure, but can also be bilateral failure. The mechanism of action that causes decreased ventilation associated with pleural effusion is the ability for the lungs to adequately expand. An increase in capillary pressure causes an increase in fluid in the plural cavity. This inhibits the ability of the lungs to expand and take in the necessary amount of air. A decrease in ventilation due to plural cavity disorders also increases the risk for the lungs to collapse. Negative pressure normally keeps the lungs from collapsing, however, when the effusion occurs the pressure becomes more positive, caused by the increase in

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