@mrbill– I'm sad that you have had such a rough time. COPD flare-ups (exacerbations) are usually caused by a trigger such as air pollution or allergens, or a chest infection from a virus (cold or flu) or bacteria. And one flare-up often leads to another as both you and @marley1 have discovered. They are dangerous because they inflame the lungs and calming them down can take a long time.
Prednisone without food is a no-no. You bring up a wonderful point. We really need to be vigilant in protecting ourselves even in the hospital. I had the same reaction as you, being given medication without food and wound up vomiting all night after I was released. We need to ask questions about the medicines that are given to us no matter where you are.
One time I was with my sister at the hospital and the person who came in to administer her an inhaler didn't know what she was doing. I had to correct her. We can't be afraid to do this.
How are you doing now? Do you have to be on O2 all the time now?