Which one of these is NOT associated with decrease in Residual Volume?
(A) Emphysema# RESIDUAL VOLUME is the amount of gas remaining in the lungs at the end of a maximal exhalation.> Residual Volume is important because it prevents the lungs from collapsing.> Even after we have expelled as much air as possible (expiratory reserve volume) gaseous exchange is still occurring by residual volume in the lungs. It also prevents the inner surfaces of the lungs sticking together.# In Chronic Bronchitis and Emphysema:> Increase in Residual volume> Peak Expiratory flow rate usually reduced.> VA/Q i.e., ventilation perfusion ratio is a poor indicator of the severity of the disease.TypeExamplesDescriptionFEV1/FVCRestrictiveLungDiseases Pulmonary fibrosis, Infant Respiratory Distress syndrome, Weak respiratory muscles, PneumothoraxVolumes are decreasedOften in a normal range (0.8 to 1.0)ObstructiveLungDiseases Asthma or COPD or EmphysemaVolumes are essentially normal but flow rates are impededOften low (Asthma can reduce the ratio to 0.6, Emphysema can reduce the ratio to 0.78 to 0.45)
Emphysema
Bacterial pneumonia
Interstitial lung disease
Lung abscess
Miscellaneous