The excess adipose tissue restricts the movement of the respiratory muscles and makes the chest wall less compliant. For unknown reasons will only some obese people develop it. Pickwick syndrome, or obesity hypoventilation syndrome, is a restrictive lung disease of obese people.

Chronic obstructive pulmonary diseases (COPD).

Many other factors can cause secondary alveolar hypoventilation: It doesn’t cause any problems by itself, however patients with primary alveolar hypoventilation may have even worse symptoms when they also develop chronic bronchitis or obesity. It is caused by a decreased CO 2-sensitivity of the respiratory centre in the CNS. Primary alveolar hypoventilation is a type of alveolar hypoventilation with no known etiology. It’s defined as when the arterial pCO 2 is increased above the normal 44 mmHg. When we take shallow breaths the ratio decreases.Īlveolar hypoventilation is when the alveolar ventilation is insufficient compared to the requirements of the body.

When we take deep breaths the ratio between alveoli ventilation and dead space ventilation increases.

350 mL reach the alveoli while 150 mL fill the dead space. The normal value of tidal volume is 500 mL. Last updated on at 10:11Īlveolar ventilation is the gas exchange within the alveoli within a certain time, often 1 minute.

Describe dead space ventilation