Lung Volumes and Capacities PDF

Lung Volumes and Capacities Dr. Iram jaan Lecturer,Physiology www.gmu.ac.ae COLLEGE OF HEALTH SCIENCES  Learning Objectives Describe lung volumes and capacities Explain FEV1 and FVC and state its im...

Lung Volumes and Capacities Dr. Iram jaan Lecturer,Physiology www.gmu.ac.ae COLLEGE OF HEALTH SCIENCES  Learning Objectives Describe lung volumes and capacities Explain FEV1 and FVC and state its importance List obstructive and restrictive respiratory diseases  Spirometer It records the lung volumes and capacities  SPIROMETER: It is an instrument used in physiological and clinical studies for determination of lung volumes and capacities. 08/10/2024 3  Lung Volumes and Capacities The total volume in the lung at the end of a maximal inspiration is subdivided into volumes and capacities.  Lung Volume Lung Capacity It is the volume Lung capacity of air that can is the sum of be inspired or two or more expired by lung volumes. breathing. www.gmu.ac.ae COLLEGE OF HEALTH SCIENCES TWO Types Of lung volume and capacities: 1 Static Lung volume and Capacities.(Time independent,Expressed in ml or litres.) 2 Dynamic Lung volume and capacities.(Time dependant ,Expressed in ml/min or L/min) Lungs Volumes and Capacities  IC (TV + IRV) VC (IRV + TV + ERV) TLC (RV + VC) FRC (ERV + RV)  Lungs Volumes 1. Tidal volume (TV) 2. Inspiratory Reserve volume (IRV) 3. Expiratory Reserve volume (ERV) 4. Residual volume ( RV )  Lungs Volumes 1. Tidal Volume (TV) It is the amount of air breathed in or out in a quiet respiration. Its value is 500 ml 2. Inspiratory Reserve Volume (IRV) It is the amount of air that can be maximally inspired by a forced inspiration after a normal inspiration. Its value is 3000 ml 3. Expiratory Reserve Volume (ERV) It is the amount of air that can be maximally expired from the end of normal expiration. Its value is 1100 ml  Lungs Volumes 4. Residual Volume (RV) It is the amount of air that remains in the lungs after a maximal expiration. Its value is 1200 ml Residual volume is increased in old age, emphysema  All lung volumes can be measured by spirometer EXCEPT the residual volume Residual volume can be measured by Helium dilution method. www.gmu.ac.ae COLLEGE OF HEALTH SCIENCES  Lung Capacities Sum of one or two volumes = Capacities 1. Inspiratory capacity (TV + IRV ) 2. Vital capacity (TV+IRV+ERV) 3. Functional residual capacity (RV+ERV) 4. Total lung capacity (TV+IRV+ERV+RV )  Lung Capacities 1. Inspiratory capacity (TV + IRV ) Maximum volume of air that can be inspired by forced inspiration after a normal expiration. Normal Value: 3500 ml 2. Vital capacity (VC ) (TV+IRV+ERV) Maximum volume of air that can be forcefully expelled from the lungs following a maximum inspiration. Normal Value: 4600 ml 3. Functional residual capacity (FRC ) (RV+ERV ) Volume of air remaining in the lungs at the end of a normal expiration. Normal value: 2300ml  4. Total lung capacity (TV+IRV+ERV+RV ) Volume of air contained in the lungs at the end of a maximal inspiration. Normal Value: 6000ml   Timed Vital Capacity (TVC) or Forced Vital Capacity (FVC)  Minute Volume (MV) or Pulmonary Ventilation (PV)  Maximum Breathing Capacity (MBC) or Maximum Ventilatory Volume (MVV) or Maximum Voluntary Ventilation. www.gmu.ac.ae COLLEGE OF HEALTH SCIENCES  Forced Vital Capacity FVC Total volume of air that can be exhaled forcefully from TLC The majority of FVC can be exhaled in