Читать книгу Manual of Equine Anesthesia and Analgesia - Группа авторов - Страница 200

 Anatomic dead space is the volume of gas that ventilates conducting airways.

 Alveolar dead space is the volume of gas not taking part in effective gas exchange at the alveolar level.

 Physiologic dead space is the sum of anatomical and alveolar dead space.

 The fraction of a tidal volume breath that occupies the physiologic dead space is commonly expressed as the VD/VT ratio.

 In normal adult horses, the VD/VT ratio is 50–75%, a value significantly greater than the VD/VT ratio in humans (15–20%).

Figure 4.2 Lung volumes in an adult horse (500 kg). TLC, Total lung capacity (55 l); VC, Vital capacity (44 l); RV, Residual volume (11 l); IC, Inspiratory capacity (29.5 l); FRC, Functional residual capacity (25.5 l); IRV, Inspiratory reserve volume (23.5 l); TV, Tidal volume (6 l); ERV, Expiratory reserve volume (14.5 l).