1. Respiratory Ventilation
B Lab
Respiratory Ventilation

2. Inspiratory Muscles Diaphragm External Intercostal Scalenes
Sternocleidomastoids
Neck & Back muscles
Upper-respiratory-tract muscles

3. Mechanics of breathing
Quiet breath: +/- 3 mmHg intrapulmonary pressure.
Forced breath:
Extra muscles, including abs
+/ mm Hg intrapulmonary pressure

4. Pulmonary Function Spirometry:
Breathe into a closed system, with air, water, moveable ball
Insert fig

5. Lung volumes Tidal volume (TV): in/out with quiet breath (500 ml)
Total minute volume: tidal x breaths/min
6 L/min
Exercise: even 200 L/min!
Anatomical dead space:
Conducting zone
Dilutes tidal volume, by a constant amount.
Deeper breaths -> more fresh air to alveoli.

6. Lung volumes
Inspiratory Reserve Volume (IRV): volume of air you could inhale with maximal effort
Expiratory Reserve Volume (ERV): volume of air one can expire with maximal effort
Forced-Expiratory Volume (FEV1): volume of air exhaled as rapidly & completely as possible in one second

7. Lung capacities
Vital capacity (VC): total volume of exhaled air from maximal inspiration to maximal exhalation
Residual volume (RV): always left in lungs, even with forced expiration.
Not measured with spirometer
Total lung capacity (TLC): VC plus residual volume
Vital capacity is the single most important pulmonary function measurement
Functional residual capacity (FRC): volume of air remaining in lung at the end of a normal exhalation; FRC is the resting volume of the lung