I was diagnosed with COPD 3 plus years ago. I also lost a lung lobe to squamous cell lung cancer.
Found out a few weeks ago that I am not ex-hailing the carbon dioxide completely. Some is staying in my lungs causing me to be more short of breath than I used to be. I had an overnight O2 test, oxygen level went below 88% for at least 8 minutes, at one point it dropped down to 72%. I had a sleep study this past Monday, hope to have results by Friday.