The entire song is about Radiohead’s “Creep” from their first album Pablo Honey. An iron lung is a mechanical respirator that worked using negative pressure to assist breathing, most commonly in polio, where patients had paralysed lungs. It effectively breathed for someone who was unable to do so.

“My Iron Lung” tells of how “Creep” is the only thing keeping Radiohead successful or alive. The iron lung metaphor is apt because while “Creep” was keeping the band alive (financially), it was also very constraining and they perceived it as forcing them to play a certain style of music. Similarly, an iron lung does not allow the patient inside it any freedom of movement.