I was blindsided by a completely unexpected drop in my FEV1 about 3 months ago. On my birthday (April 28) I felt fabulous. I had more energy than ever it seemed. I even did a 12-hour round trip to Phoenix by myself to visit a friend just 2 days later. When I had a clinic appointment on May 2, I was fully expecting that my spirometry would show that I was in the best shape I'd been in months. Not so. I dropped 15% and ended up in the hospital.
Now I'm feeling really good. My FEV1 is higher, my pulse ox has improved from 88 to 97, and my peak flow is about 480L/min. I think over the last year I had gotten so used to being "sick and tired" that the gradual decline was nearly imperceptible. Sort of like leaving a glass of water out for a few weeks. The evaporation is obviously taking place, but you can't see the day to day drop in the level of the water. I think that's how the decline is for a lot of us as we lose lung function. Sometimes we're able to gather up the metaphorical water droplets and condense them into our glass. This may make it a little fuller for awhile, but eventually nature wins out and evaporation will empty the glass.
Not to get overly philosophical about it, but that analogy makes me realize even more so that life is just a vapor. "Why, you do not even know what will happen tomorrow. What is your life? You are a mist that appears for a little while and then vanishes." (James 4:14, NIV) I'm so thankful that when my life on earth is finished, my eternity is secure with Christ in heaven.