The 2 min. video below talks about a woman who has had to rely on an iron lung for over 50 years, after catching polio as a little girl.
So, Mark, just what is an Iron Lung?
An iron lung is a machine that enables a person to breathe when normal muscle control has been lost or the work of breathing is too much for the person to handle.
OK. Well, what is Polio?
Polio, caused by the RNA virus named Poliovirus, first enters the body through the mouth, infects a person's bloodstream, and then sneaks into the central nervous system by getting into the spinal cord.
[Read more about Poliovirus pathophysiology]
When the virus enters the nervous system, it damages the nerves that control your body's muscles, and thus it causes rapid paralysis.
Overall, 5–10% of patients with paralytic polio die due to the paralysis of muscles used for breathing.
How did the iron lung help polio patients?
Now it all starts coming together! As you now know, polio can cause your breathing muscles to be paralyzed, which would quickly lead to death.
With the iron lung, the patient lies within a sealed chamber and provides an effective oscillating atmospheric pressure. The pressure inside the machine goes up and down, just like the muscles in your chest cause the pressure in your lungs to go up and down, causing you to breathe.
| Poliovirus |
|---|
 Electron micrograph of poliovirus virions. |
An Iron Lung Ward filled with Polio patients, Rancho Los Amigos Hospital, California (1953)
