Uses
Lung plethysmography may be ordered for several reasons.
Some of these include:
How Does Plethysmography Work?
Plethysmography measures the total amount of air your lungs can hold.
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Before the Test
You will be able to drive yourself to and from the test.
You should avoid doing anything that could inhibit your ability to breathe comfortably during the test.
If you ordinarily use oxygen, you will not need to receive your oxygen during the test.
A technician will place clips on your nose and give you a mouthpiece to breathe through.
Overall, the active part of this test takes around 15 minutes.
What the Test Measures
Plethysmography measures the amount of air that you exhale.
It helps your healthcare professionals understand how well your lungs are functioning.
The results of this test help your practitioner calculate other pulmonary functions as well.
Lung diseases can be classified based on whether your functional residual capacity is increased, decreased, or normal.
The results can also vary based on age, sex, height, and weight.
With conditions such asemphysema, the full volume of air is not exhaled from the lungs after each breath.
The elastic recoil is damaged so that extra air is left over.
This can have several causes.
The lungs might not be able to expand normally, either due to external or internal factors.
Broaddus, V. Courtney, and Robert J. Mason.Murray & Nadel’s Textbook of Respiratory Medicine.
Elsevier Saunders, 2016.
Criee, C., Sorichter, S., Smith H. et al.Body Plethysmography Its Principles and Clinical Use.Respiratory Medicine.
105(7):959-971.
U.S. National Library of Medicine.
Zysman-Colman, Z., and L. Lands.Whole Body Plethysmography: Practical Considerations.Paediatric Respiratory Reviews.
