Status Asthmaticus

Closing Doors in a Crowded Building

Imagine a tall office building where fresh air must flow in through the lobby doors and up the stairwells to each floor, then stale air must flow back out. The doors are like your airways — they have muscles that can squeeze them shut. During a fire drill, a panic alarm goes off (the trigger) and someone accidentally hits the door-closing mechanism over and over with a remote (repeated albuterol). The muscle gets exhausted and stops responding to the remote (receptor down-regulation). At the same time, someone is spraying thick foam on the stairs and the door frames are swelling shut (mucus and mucosal swelling (edema)). Air rushes in when people push hard, but it gets stuck on the way out because the floppy doors collapse closed before everyone can leave. More and more people pile up inside the building, packed shoulder to shoulder on every floor (air trapping and hyperinflation). The people upstairs cannot breathe, the cleanup crew cannot clear the foam, and the building's support beams start to crack from the pressure (respiratory muscle fatigue, hypercapnia, and risk of barotrauma). Without opening those doors wide or cutting a new exit route, people will suffocate and the building collapses (respiratory arrest and cardiac arrest).