Pulmonary function
1 like468 views
- Pulmonary function tests measure lung capacity and airflow. Spirometry evaluates volumes like forced vital capacity (FVC) and flows like forced expiratory volume in 1 second (FEV1). Restrictive lung diseases decrease total lung capacity while obstructive diseases decrease FEV1/FVC ratio. Common tests include spirometry, plethysmography, and gas diffusion tests. Interpreting patterns can help diagnose conditions like asthma, emphysema, and chronic bronchitis.
Pulmonary function
- 1. PULMONARYPULMONARY FUNCTIONFUNCTION Dr. G. Praveen KumarDr. G. Praveen Kumar Department of Pharmacy PracticeDepartment of Pharmacy Practice Sri Ramachandra UniversitySri Ramachandra University
- 4. The Alveoli • Approximately 300 million alveoli • 1/3 mm diameter • Total surface area if they were complete spheres 85 sq. meters (size of a tennis court)
- 5. TOTAL LUNG CAPACITY (TLC): The maximum amount the lungs can be expanded with the greatest inspiratory effort (vital capacity plus residual volume)
- 6. VITAL CAPACITY (VC): The maximum amount of air expired after filling the lungs to their maximum.
- 7. TIDAL VOLUME (TV): The amount of air inspired or expired with normal respiration
- 8. EXPIRATORY RESERVE VOLUME (ERV): The amount of additional air that can be expired by forceful expiration after the end of a normal tidal expiration.
- 9. FORCED VITAL CAPACITY (FVC): Maximum expiratory effort (as rapidly and completely as possible) following maximum inspiration to total lung capacity
- 10. INSPIRATORY CAPACITY (IC): The amount of air inspired beginning at the normal expiratory level and filling the lungs to the maximum amount (tidal volume plus inspiratory reserve volume)
- 11. ONE-SECOND FORCED EXPIRATORY VOLUME (FEV1): The amount of air that is expired in the first second of the forced vital capacity. It may be expressed as volume in L or as a percentage of forced vital capacity
- 12. PEAK EXPIRATORY FLOW RATE (PEFR): The maximum flow rate that occurs at any time during the forced vital capacity
- 13. RESIDUAL VOLUME (RV): Amount of air remaining in the lungs following a forceful expiration.
- 15. NORMAL VALUES FOR ADULTSNORMAL VALUES FOR ADULTS Dead space volumeDead space volume 100-200 mL100-200 mL Expiratory reserve volume (ERV)Expiratory reserve volume (ERV) 1-2 L1-2 L Forced vital capacity (FVC)Forced vital capacity (FVC) 4 L*4 L* Functional residual capacity (FRC)Functional residual capacity (FRC) 2-3 L2-3 L Inspiratory capacity (IC)Inspiratory capacity (IC) 2-4 L2-4 L One-second forced expiratory volume (FEV1)One-second forced expiratory volume (FEV1) (> 70% FVC)(> 70% FVC) 3-4 L*3-4 L* Peak expiratory flow rate (PEFR)Peak expiratory flow rate (PEFR) 9-10 L/sec9-10 L/sec Residual volume (RV)Residual volume (RV) 1-2 L1-2 L Tidal volume (TV)Tidal volume (TV) 500 mL500 mL Total lung capacity (TLC)Total lung capacity (TLC) 6-7 L*6-7 L* Vital capacity (VC)Vital capacity (VC) 4-5 L*4-5 L*
- 16. FVC Interpretation of % predicted: –80-120% Normal –70-79% Mild reduction –50%-69% Moderate reduction –<50% Severe reduction
- 17. FEV1 Interpretation of % predicted: • >75% Normal • 60%-75% Mild obstruction • 50-59% Moderate obstruction • <49% Severe obstruction
- 18. PEAK FLOW METER Its a small, hand-held device used to monitor a person's ability to breathe out air. It measures the airflow through the bronchi and thus the degree of obstruction in the airways.
- 21. Gas diffusion tests Gas diffusion tests measure the amount of oxygen and other gases that cross the lungs' air sacs (alveoli ) per minute. These tests evaluate how well gases are being absorbed into your blood from your lungs.
- 22. PLETHYSMOGRAPHY The patient sits inside an airtight box, inhales or exhales to a particular volume and then a shutter drops across their breathing tube. The subject makes respiratory efforts against the closed shutter causing their chest volume to expand and decompressing the air in their lungs.
- 26. Restrictive Lung Disease Pleural Parenchymal Chest wall Neuromuscular
- 27. Obstructive Lung Disease Asthma COPD - chronic bronchitis - emphysema Bronchiolitis Upper airway obstruction
- 28. Obstructive Pattern — Evaluation Spirometry FEV1, FVC: decreased FEV1/FVC: decreased (<70% predicted) Lung Volumes TLC, RV: increased
- 29. Restrictive Pattern – Evaluation Spirometry FVC, FEV1: decreased FEV1/FVC: normal or increased Lung Volumes TLC, RV: decreased
- 30. MEASUREMENT OBSTRUCTIVE RESTRICTIVE Forced vital capacity (FVC) Decreased or normal Decreased Forced expiratory volume in 1 second (FEV1) Decreased Decreased or normal FEV1 /FVC ratio Decreased Normal Total lung capacity (TLC) Normal or increased Decreased
- 31. Asthma FEV1/FVC normal or decreased Emphysema FEV1/FVC <70% TLC increased Increased compliance Chronic Bronchitis FEV1/FVC <70% TLC normal Normal compliance
- 33. Save Nature & Save Breathe… Thank You