Lungs volume and Capacities

To study different types of lungs volume and lungs capacities

1. Respiratory system Lung volumes and capacities Mr N.JEGAN Associate Professor K.M.COLLEGE OF PHARMACY. MADURAI.

2. Respiratory system

3. Lungs volume-Introduction Lung volumes are also known as respiratory volumes. In normal quiet breathing there are about 15 respiratory cycles per minute.

4. Importance to measure the lungs volume Lung function tests are based on the measurement of volume of air breathed in and out in quiet breathing and forced breathing. These volumes tend to vary, depending on the depth of respiration, gender, age, body composition and in certain respiratory diseases. It used to find the person have any lungs related diseases.

5. Lung volumes Lung volumes are the volumes of air breathed by an individual. Lung volumes are of four types: 1 . Tidal volume 2. Inspiratory reserve volume 3. Expiratory reserve volume 4. Residual volume

6. Tidal volume(TV) This is the amount of air which passes into and out of the lungs in a single normal quiet respiration. Normal value-500 ml

7. Inspiratory reserve volume(IRV) It is an additional volume of air that can be inspired forcefully after the end of normal inspiration. Normal value-3300 ml

8. Expiratory reserve volume(ERV) It is the additional volume of air that can be expired out forcefully, after normal expiration. Normal value-1000 ml

9. Residual volume(RV) It is the volume of air remaining in lungs even after forced expiration. Normally, lungs cannot be emptied completely even by forceful expiration. Some quantity of air always remains in the lungs even after the forced expiration. Normal value-1200 ml

10. LUNG CAPACITIES Lung capacities are the combination of two or more lung volumes. Lung capacities are of four types: 1. Inspiratory capacity 2. Vital capacity 3. Functional residual capacity 4. Total lung capacity.

11. Inspiratory capacity(IC) It is the maximum volume of air that is inspired after normal expiration (end expiratory position). It includes tidal volume and inspiratory reserve volume IC = TV + IRV IC= 500 + 3,300 = 3,800 ml Normal value-3800 ml

12. Vital capacity(VC) It is the maximum volume of air that can be expelled out forcefully after a deep (maximal) inspiration. VC includes inspiratory reserve volume, tidal volume and expiratory reserve volume. VC = IRV + TV + ERV VC= 3,300 + 500 + 1,000 = 4,800 ml Normal value-4800 ml

13. Functional residual capacity(FRC) It is the volume of air remaining in lungs after normal expiration (after normal tidal expiration). Functional residual capacity includes expiratory reserve volume and residual volume. FRC = ERV + RV FRC= 1,000 + 1,200 = 2,200 ml Normal value-4800 ml

14. Total lung capacity(TLC) It is the volume of air present in lungs after a deep (maximal) inspiration. It includes all the volumes . TLC = IRV + TV + ERV + RV TLC= 3,300 + 500 + 1,000 + 1,200 = 6,000 ml Normal value- 6000 ml

15. Lungs capacities- Diagram

16. How to measure Lungs volume Apparatus name-The Spirometer A spirometer is an apparatus for measuring the volume of air inspired and expired by the lungs. you sit and breathe into a small machine called a  spirometer . This medical device records the amount of air you breathe in and out and the speed of your breath.

17. Spirometer

18. Thanking you

19. Next Topic Artificial respiration, and resuscitation methods.