I had the pleasure of performing a pulmonary function test (PFT), chilling with my lung doc and getting chest x-rays Wednesday. A PFT can feel like running a marathon while sitting in a chair with a tube coming out of your mouth. I’d much rather go running than do these things, but you get used to them. At one point in my life I was having to do PFTs every few weeks and sometimes multiple times in a single doctor visit.
If you’ve never done a PFT or are going to and wonder what happens, I’ll give you the cliff notes.
- Your weight and height should be measured
- You sit in a chair
- Some clips are put on your nose so you’re only breathing through your mouth
- You’ll be asked to breathe into a tube at varying rates, take a deep breath and hold it, etc
I’ve had some doctors give me a “PFT” which consisted of me simply exhaling into a tube. To me this just seems like a Peak Flow meter. The important thing to remember when doing one of these is to play it cool like the Fonz. If you’re uptight and try to fight it, you’ll just have to repeat everything.
Once you’re done there will be different numbers your doctor will go over with you. The easiest value for me to understand is the FEV1/FVC ratio. Based on your age, height and weight there’s be an expected ratio compared to how you actually performed. FEV stands for forced expiratory volume and FEV1 is the most air you can breathe out in one second. FVC stands for forced vital capacity or the most air you can exhale after inhaling as much as possible.
Like everything else, there are multiple ways to interpret this ratio, but if you’re within 80%-120% of expected, things are supposed to be normal. The hard thing for some doctors to realize is “your normal” may have nothing to do with textbook normal. Over the past 6 years I’ve gone from 135% to about 95%. I’m still “normal,” but have lost 40% of my lung function and it keeps decreasing every time it’s measured.
The good news is that I am coughing less, wheezing less and hurting less when breathing. I feel like I’ve been able to do more in the past six months than I have in the past couple years. I can’t really say I feel good, but things aren’t nearly as bad as last fall.