Hi. njb. Thank you for your post. "Barrel chest" is an old term describing how your chest appears to be of a "barrel" shape. This is because people with COPD (and also during asthma attacks) have obstructed airways. Air can get in past the obstructions, but has a hard time getting out. This causes a slow expiration. And this also causes air to become trapped inside your lungs. As air gets trapped, this makes it look like you are always inhaling -- and that is how it shows up on an x-ray. A modern term for this is "hyper-inflated" lungs. Does this make sense. We also have various articles describing this process in more detail. I will post a link to them here (https://copd.net/search?s=barrel%20chest). Does this help? John. Community Moderator. copd.net