: belonging only to the person or group specified. 1  She has the sole authority to hire new staff members. [=only she can hire new staff members] 2  He has sole jurisdiction of the area.
Dr. Stern responded: Dead space in lung. Dead space is a term used to describe an area of the lung where gas exchange cannot occur - it does not mean dead lung tissue. Everyone has dead space and it is comprised mainly of your airways. It is measured as a percentage. Dead space is affected by many variables including the size of the breath we inhale.
A collapsed lung occurs when air escapes from the lung. The air then fills the space outside of the lung, between the lung and chest wall. This buildup of air puts pressure on the lung, so it cannot expand as much as it normally does when you take a breath. The medical name of this condition is pneumothorax.