Overview
- The residual volume is the volume left in the lungs after a maximal expiration.
Increased Residual Volume
- An increase in residual volume is suggestive of gas trapping.
Causes of Increased Residual Volume
- Asthma
- Emphysema
Reduced Residual Volume
- A reduction in residual volume suggests a parenchymal cause of restrictive lung disease.
Causes of Reduced Residual Volume
- Pulmonary fibrosis
- Sarcoidosis
- Atelectasis
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