I was released from the hospital (after 2-1/2 months) almost exactly a month and a week ago, and Wednesday, it appears I suffered an exacerbation. My blood O2 sat dropped from a steady 98-99 to under 70 in less than 24 hours. I called a home health care nurse and she didn't seem overly alarmed. I don't seem to have any sort of infection; a little more phlegm than usual. What can I do to get my O2 levels back up?? I'm a first time poster -- thanks for your response.