: 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.
Pneumothorax is a condition in which air or gas collects in the pleural space or pleural cavity, which is the space between the lungs and the chest cavity. This can cause the lung to collapse. Normally, the lungs sit next to the inner surface of the chest wall. Thin membranes called pleura cover both the lungs and the chest wall. A pneumothorax occurs when air either escapes the lung or leaks in through the chest wall and builds up in the pleural space between them. This build-up of air can result in the collapse of the affected lung. There are different types of pneumothorax, and each one is defined by its cause.