How would the flow volume curve change with restrictive lung disease?
Restrictive disease: the flow-volume curve is narrowed because of diminished lung volumes, but the shape is generally the same as in normal volume. Flow rates are greater than normal at comparable lung volumes because the elastic recoil of lungs holds the airways open.
What does shallow lung volumes mean?
Low lung volume If your lung volume is lower than normal, this may be a sign of a restrictive lung condition such as pulmonary fibrosis or sarcoidosis.
What is a flow volume curve?
The flow-volume loop (F/V-loop) is a presentation of inhalation and exhalation of air stream volume during inspiration and expiration. It demonstrates the obstructive, restrictive and mixed pattern lung pathology.
How do intrathoracic obstruction and extrathoracic obstruction affect a flow volume loop?
Finally, a fixed intrathoracic or extrathoracic obstruction affects both inspiration and expiration, giving a flow volume loop that has an overall box-like shape as both inspiratory and expiratory limbs flatten.
How is the interpretation of flow-volume curves done?
The aim of the experiment is interpretation of flow-volume curves. The subject is asked to breathe into the spirometer. The subject is asked to take a deep breath and exhale with complete forced expiration. The different flow –volume curves are interpreted based on the values.
What is the value of VC on a flow curve?
The different flow –volume curves are interpreted based on the values. VC (vital capacity): This is the maximum volume of air exhaled or inspired during maximally forced (FVC) or slow (VC) manoeuvre, VC is normally equal to FVC.
What are the features of the flow-volume loop?
Characteristic features of restrictive lung disease in the flow-volume loop include the following: 1 Low tidal volume 2 Rapid decrease in inspiratory flow 3 Rapid expiratory flow, with a high peak expiratory flow rate (as the inelastic lung recoils) More
Which is the Maximal expiratory flow-volume curve?
Maximal expiratory flow-volume curve- This is the plot of maximal expiratory flow (Vmax) against volume during the performance of a forced expiratory vital capacity (FVC) maneuver. The inspiratory part of F-V curve depends on factors like airway resistance and strength of inspiratory muscles.