1 / 37

Pulmonary Function Tests

This detailed guide explores various pulmonary function tests and lung mechanics essential for understanding respiratory health. It covers aspects like lung resistance and compliance, distribution of ventilation, maximal respiratory pressures, and the V/Q ratio. Measurement techniques such as nitrogen washout, inert gas dilution, and plethysmography are discussed. The impact of lung volume on airway resistance is also analyzed, along with exercise-induced respiratory challenges and mechanisms of hypoxemia. This information serves as a foundational resource for healthcare professionals assessing lung function.

yvonnedominguez
Télécharger la présentation

Pulmonary Function Tests

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Pulmonary Function Tests Other tests of lung function:1. Lung mechanics-Resistance -Compliance 2. Distribution of Ventilation (N2 delta) 3. Maximal Respiratory Pressures (MIP, MEP)

  2. V/Q ratio

  3. V/Q mismatch (3-compartment model)

  4. Lung volumes and capacities

  5. How to measure FRC (RV,TLC) ? • Nitrogen washout method • Inert gas dilution technique • Plethysmography

  6. Resistance

  7. Volume dependence of airway resistance (Raw) 4 3 SRaw (cmH2O/L/sec) 2 1 0 2 4 6 8 Lung Volume (liters) RV TLC

  8. Compliance

  9. Compliance

  10. Ventilatory Mechanics: Healthy 100 % VC Pcw 80 PRS 60 40 PL 20 0 20 40 60 -60 -40 -20 0 Pressure (cmH2O)

  11. 4 3 2 SRaw (cmH2O/L/sec) 1 0 2 4 6 8 Lung Volume (liters) Ventilatory Mechanics: Healthy ΔPΔV 100 ΔP ΔV % VC RV 80  elastic WOB 60 elastic and resistive work of breathing is minimized when tidal breathing occurs within the compliant portion of the respiratory systems P-V curve TLC 40 ΔPΔV 20  resistive WOB 0 20 40 60 -60 -40 -20 0 Pressure (cmH2O) SRaw as lung volume  because the airways distend as the lungs inflate, and bigger airways have lower resistance (*Poiseuilles’ Law*). The opposite is also true, of course!

  12. Ventilatory Mechanics: Healthy Begin Exercise IC IC VT

  13. 8  EILV 6 Volume (liters) 4  EELV 2 0 -40 -30 -20 -10 0 10 20 30 40 50 Pressure (cmH20) Ventilatory Mechanics: Healthy TLC  IRV  IC  VT EELV RV

  14. Dynamic hyperinflation during exercise IRV IRV

  15. Diffusion capacity (DLCO, DLCO/VA, Tco, Kco)

  16. Mechanism of hypoxaemia

  17. Hypoxaemia, hypercapnia in clinical cases

  18. Respiratory and metabolic shifts chronic acute acute chronic

  19. Exercise tests in lung diseases • Exercise-induced asthma (EIA) - FEV1 • Interstitial lung disease (ILD)- SAT • Exercise tolerance in rehabilitation (COPD) - cardiopulmonary exercise (CPX). Important variables: - work rate (watts), SpO2, ABG - VO2, VCO2, RQ, VE - lactate threshold (LT) - breathing reserve (1-VEmax/MVV) - heart rate reserve (1-HRmax/220-age)

  20. Mechanism of exercise-induced hypoxaemia

  21. Noninvasive determination of lactate threshold by the V-slope method

More Related