In the early 20th century, polio was one of the most feared diseases in industrialized countries, paralysing hundreds of thousands of children every year. A highly infectious disease, polio attacks the nervous system and can lead to paralysis, disability and even death. The symptoms – pain and weakness, fatigue and muscle loss – can strike any time from 15 to 50 years after the initial disease. In 1952, more than 21,000 Americans contracted a paralyzing form of polio, and 3,000 died from it. Once infected, there was no treatment besides time and tending to the symptoms.
No device is more associated with polio than the tank respirator, better known as the iron lung. Physicians who treated people in the acute, early stage of polio saw that many patients were unable to breathe when the virus’s action paralyzed muscle groups in the chest. Death was frequent at this stage, but those who survived usually recovered much or almost all of their former strength.
Nothing worked well in keeping people breathing until 1927, when Philip Drinker and Louis Agassiz Shaw at Harvard University devised a version of a tank respirator that could maintain respiration artificially until a person could breathe independently, usually after one or two weeks. The machine was powered by an electric motor with two vacuum cleaners. The pump changed the pressure inside a rectangular, airtight metal box, pulling air in and out of the lungs.
Inventor John Emerson had refined Drinker’s device and cut the cost nearly in half. Inside the tank respirator, the patient lay on a bed (sometimes called a “cookie tray”) that could slide in and out of the cylinder as needed. The side of the tank had portal windows so attendants could reach in and adjust limbs, sheets, or hot packs.
The National Foundation for Infantile Paralysis began mass distribution of tank respirators in 1939.
In the 1930s, an iron lung cost about $1,500—the average price of a home.
In 1959, there were 1,200 people using tank respirators in the United States; in 2004, there were 39.