This is about a third of the resting tidal volume (450-500 mL).Īnatomic dead space is the volume of the conducting airways. This is the same conversion of kilograms to pounds, except the final unit is in mL. 1 mL per lb or 2.2 mL per kilogram of body weight.

A 150 lb (68 kg) male would have an anatomical dead space of about 150 mL. It is normally equal in milliliters to your body weight in pounds.

Birds, which, relatively, have a far longer and wider trachea than mammals, have a higher proportion of dead space. TOTAL DEAD SPACE (also known as “PHYSIOLOGICAL” DEAD SPACE) can be divided into anatomical dead space and alveolar dead space.Īnatomical dead space is the gas in the conducting areas of the respiratory system, such as the mouth and trachea, where air does not come into contact with the alveoli of the lungs. Some of the air a person breathes never reaches the gas exchange areas but simply fills respiratory passages where gas exchange does not occur, such as the nose, pharynx, and trachea.This air is called dead space air because it is not useful for gas exchange.

“The normal dead space air in a young adult man is about 150 millilitres. 150 ml REF: Guyton physiology 11th edition page 478, hysiology%29#Anatomical_dead_space

Tracheostomy physiological dead space