Portable ventilators blow air, sometimes with extra oxygen, into the lungs of a person experiencing difficulty breathing. This is done by inserting a breathing tube into the windpipe (also known as the trachea) of the patient. This pipe allows air into the lungs, bypassing the vocal cords in the process. In a process known as intubation, the tube is first inserted into the trachea via the throat or nose, and a ventilator is hooked up that breathes for the patient. Intubation is...