I hadn't either until last week. My breathing problems since late 2008 became markedly worse after my eye removal surgery in February. Finally I was able to see a pulmonologist who immediately had a diagnosis. It took exactly one week to go from his tentative diagnosis to an operating room.
A tracheal stenosis is a narrowing of the trachea which can be idiopathic in causation, from accident, chemical exposure, or intubation. In my case, they don't have a handle on the initial cause, but suspect intubation during my eye surgery exacerbating an existing stenosis making things go from bad to horrible. By the time of the surgery, I was breathing through a hole 3 millimeters in diameter.
I am home doing the couch and book thing while I recover. There's no serious pain, but I do have no energy. Fighting for breath over the past few months has drained me thoroughly and probably been the reason I haven't recovered from the eye surgery. I am taking some time to rest including a break from blogging until June 2nd.
Hopefully I'll be back better than ever.