The iron lung, a type of negative pressure ventilator, played a crucial role in medical history, particularly during the polio outbreaks of the mid-20th century. This mechanical respirator, which encloses most of a person's body, was designed to assist breathing when muscle control was lost. Although its use has largely become obsolete due to advancements in medical technology, the iron lung remains a significant chapter in the history of respiratory
care.
The Birth of the Iron Lung
The concept of external negative pressure ventilation was first introduced by John Mayow in 1670. However, it wasn't until 1927 that the iron lung was developed by Philip Drinker and Louis Shaw. The device was initially used to treat coal gas poisoning, but it gained prominence for its ability to treat respiratory failure caused by polio. The first clinical use of the iron lung occurred in 1928, marking a significant advancement in medical technology.
In 1931, John Haven Emerson introduced an improved and more affordable version of the iron lung. This innovation made the device more accessible to hospitals, further cementing its role in treating polio patients. The Both respirator, invented in Australia in 1938, offered a cheaper and lighter alternative to the Drinker model. British philanthropist William Morris financed the production of the Both–Nuffield respirators, donating them to hospitals throughout Britain and the British Empire.
The Iron Lung's Role in Polio Treatment
During the polio outbreaks of the 1940s and 1950s, iron lungs filled hospital wards, assisting patients with paralyzed diaphragms in their recovery. The device's ability to cycle air pressure inside a sealed cylinder facilitated inhalation and exhalation, mimicking the natural breathing process. This was particularly important for polio patients who had lost control of their respiratory muscles.
The widespread use of iron lungs during this period highlighted the device's importance in medical care. It provided a lifeline for many patients, allowing them to breathe despite severe muscle paralysis. The iron lung's role in treating polio was a testament to the ingenuity of medical inventors and the impact of technological advancements on patient care.
Decline and Legacy
With the development of polio vaccination programs and modern ventilators, the use of iron lungs has nearly disappeared in the developed world. Positive pressure ventilation systems, which blow air into the patient's lungs via intubation, have become more common than negative pressure systems like iron lungs. However, negative pressure ventilation is more similar to normal physiological breathing and may be preferable in rare conditions such as central hypoventilation syndrome.
As of 2026, after the death of Martha Lillard, there are no U.S. patients using an iron lung. Despite its decline, the iron lung remains a symbol of medical innovation and the fight against polio. Its legacy continues to inspire advancements in respiratory care, reminding us of the importance of adapting technology to meet the needs of patients.
