Chapter 22 - The respiratory system (part b), The following will be discussed in this chapter: Respiratory volumes; respiratory capacities; dead space; pulmonary function tests; nonrespiratory air movements; gas exchanges between blood, lungs and tissues;. | 22 The Respiratory System: Part B Respiratory Volumes Used to assess a person’s respiratory status Tidal volume (TV) Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Figure Respiratory volumes Tidal volume (TV) Amount of air inhaled or exhaled with each breath under resting conditions 3100 ml Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Amount of air remaining in the lungs after a forced exhalation 500 ml Amount of air that can be forcefully inhaled after a nor- mal tidal volume inhalation Amount of air that can be forcefully exhaled after a nor- mal tidal volume exhalation 1200 ml 1200 ml Measurement Description Adult male average value 1900 ml 500 ml 700 ml 1100 ml Adult female average value Respiratory Capacities Inspiratory capacity (IC) Functional residual capacity (FRC) Vital capacity (VC) Total lung capacity (TLC) Figure Respiratory capacities (b) Summary of respiratory volumes and capacities for males and females Functional residual capacity (FRC) Volume of air remaining in the lungs after a normal tidal volume expiration: FRC = ERV + RV Maximum amount of air contained in lungs after a maximum inspiratory effort: TLC = TV + IRV + ERV + RV Maximum amount of air that can be expired after a maxi- mum inspiratory effort: VC = TV + IRV + ERV Maximum amount of air that can be inspired after a normal expiration: IC = TV + IRV Total lung capacity (TLC) Vital capacity (VC) Inspiratory capacity (IC) 6000 ml 4800 ml 3600 ml 2400 ml 4200 ml 3100 ml 2400 ml 1800 ml Figure Inspiratory reserve volume 3100 ml Tidal volume 500 ml (a) Spirographic record for a male Expiratory reserve volume 1200 ml Residual volume 1200 ml Functional residual capacity 2400 ml Inspiratory capacity 3600 ml Vital capacity 4800 ml Total lung capacity 6000 ml Dead Space Some inspired air never contributes to gas exchange Anatomical dead space: volume of the conducting zone conduits (~150 ml) Alveolar | 22 The Respiratory System: Part B Respiratory Volumes Used to assess a person’s respiratory status Tidal volume (TV) Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Figure Respiratory volumes Tidal volume (TV) Amount of air inhaled or exhaled with each breath under resting conditions 3100 ml Inspiratory reserve volume (IRV) Expiratory reserve volume (ERV) Residual volume (RV) Amount of air remaining in the lungs after a forced exhalation 500 ml Amount of air that can be forcefully inhaled after a nor- mal tidal volume inhalation Amount of air that can be forcefully exhaled after a nor- mal tidal volume exhalation 1200 ml 1200 ml Measurement Description Adult male average value 1900 ml 500 ml 700 ml 1100 ml Adult female average value Respiratory Capacities Inspiratory capacity (IC) Functional residual capacity (FRC) Vital capacity (VC) Total lung capacity (TLC) Figure Respiratory capacities (b) Summary of respiratory volumes and .
