PFT Reliability

[Emily65Roses]

So I was just talking with a CFer from the board about PFTs. We decided we agree on something about them and I want to ask everyone else’s opinions.

It seems that PFTs aren’t as reliable as they seem to be. The girl I was talking to had pretty low PFTs before her last round of IVs, but she didn’t feel like she was as low as they read. I had PFTs over my Christmas break. The numbers were excellent. I had an FEV1 of 90%. I was surprised, and kind of pleased. At the same time, on the drive home, Mike asked me why I wasn’t jumping for joy that my PFTs were that high. I told him that the numbers may read 90, but I don’t feel like I’m a 90. So though I’m happy the PFTs read so well, I’m not going to take it too much to heart. Especially because over the last few years, I’ve been getting lower (though not too much, don’t get me wrong, I’m not looking for pity and I’m not going to drop dead here, haha). As the week went on and I kept having violent coughing fits, he slowly understood what I meant. That I wasn’t just being a bummer, that I wasn’t just being pessimistic.

My basic question here is, does anyone feel this way about PFTs? They don’t always seem so reliable to me. I’m not saying they’re entirely wrong, or totally useless (for instance, my small airway numbers are in the 30s and 40s, and that sounds right on – my small airways suck, and very often all the numbers seem right on). But does anyone else ever feel, at least on occasion, like their PFTs aren’t a really accurate representation of how they feel?

 

[NoDayButToday]

I definitely do. Mine were very low about 2 months ago, and while I wasn't exactly feeling great, I was still up and around. I didn't really feel like my numbers reflected the actual level of "life function" I had.

Sometimes, I also notice that from Trial to Trial (as in, number of 'blows' you do) there can be as much as a 15% range. For example the FEV1s for the trials will be 52%, 59%, 64%, and 66% (I'm actually not sure what my numbers are this instant, those are just examples).

 

[EmilysMom]

That's kind of funny that Emily brings this up now, because I was wondering the same thing after her PFT's in December. I really thought she would come home from her clinic visit with IV meds. Her coughing fits had gotten really bad and I know she felt LOUSY, so when she came home and said her number was at 90%, it shocked the hell out of me. There were other times when she seemed really pretty good and her numbers had dropped to like 40% and that didn't make sense to me either. I would like others comments on this also.

 

[Dea]

I feel the same way also. My last visit I just knew my pfts were going to be lower. They hadnt dropped but just a couple ...which is nothing. My FEV is about 70%...and there are times I feel like they are much lower. I see just a slow drop each time I go...<img src="i/expressions/face-icon-small-confused.gif" border="0">
Dea
31 w/CF

 

[anonymous]

I often feel that way. There have been many times that I listen to Cory Cough all night long, have difficult times, sleeping more and so forth. I call the doctor and the pft comes back "unchanged". I swear the doctor looks at me like I am completely crazy

 

[anonymous]

My FEV1 is around 30% and my O2 sats are 94-95% and I'm able to do basically anything I need to, like shop, do one flight of stairs w/o being winded, get around each morning w/o getting tired out from showering & getting dressed, go to work (desk job), etc. I couldn't do aerobics as far as I know, but I've always wondered if my numbers are actually higher than reflected on PFT's.
Yet when I do my PFT's, they consistantly seem to be in the 30% range, sometimes a little higher? It's hard to know. I've never had a scan of my lungs, only chest x-rays. I would be curious to see what kind of lung damage is reflected on a scan of some type--then again, maybe I wouldn't want to know <img src="i/expressions/face-icon-small-confused.gif" border="0">
Elle

 

[UKBASEDJON]

Hi Emily

Interesting point. I would imagine most PWCF have felt at odds with their breathing results at some times in their lives. Sometimes better, sometimes worse. At my clinic the doctors always say that the results are a guide only as many factors influence the results, even your psychological state. I suppose in reality how you actually feel is the most important measure.

Try looking at this link if you have not already seen it. http://www.cystic-l.org/handbook/html/pft_s_explained_for_you.htm

Regards

Jon

 

[anonymous]

Emily-

I completely agree with you and through my whole life have struggled with trying to tell myself that "they are just numbers."!

i have very low pft's, 35%-45%, and i can do anything, run, exercise, whatever. However they are lower because i am missing a lobe, so i guess they could relatively be considered in the 50%'s. What I have noticed though is that the difference in my pfts is HUGE between morning and afternoon. If I have an appt. at 10 am i can feel the difference when I do the blows, everything...and sure enough my pft's are wicked low. If I go back the same day (and i have done this just to see), and do my pft's again around 4pm, they go up at least 10-15 numbers. To me that seems absurd!! Now I only take appointments that are after 3, no exceptions! Even though they are just numbers I like the better numbers to be the ones that end up on the sheets. Plus, no matter how much you tell doctors this I still always kind of feel like they are trying to see if I am just in denial about my low numbers. I try to tell them that it might be because my appointment is at 9 am and I just woke up and and still coughing (i always cough in the morning, then it goes away significantly), and they just nod thier and and smile and say 'well maybe'.


anyway...thats my bit. PFT's have started to cause me serious anxiety even though I try not to let them.

Caitlin

 

[anonymous]

Some of my worst PFT's I have felt my best and some of my best PFT's I have felt my worst. I am a RRT that have done hundeds of tests on people and have learned a few secrets in getting a best effort. With that being said, your tests will vary from PFT machine and technician. Some coaches are better than others.
But for consistency sake try to use the same routine every test. The most important thing is never do your tests early in the morning. Make your appointments late in the afternoon. There are many fancy reasons why, which I will not get into, but just don't do it. A SECRET that works for me, I try to go for a jog or a brisk walk right before my test. I believe "expanding" my lungs before the test has to be a plus. I also never eat before a test, leaves more rome to breathe! The last two comments have no scientific proof, just my personal belief. As for how we feel before our tests, don't ever let the numbers dictate your life, my FEV1 runs between 65% and 73% and I still run 5K races, slowly but I get them done. Our disease is a slow one and happens so slowly that we don't notice. That is one blessing in fight, we don't even know we are sick have the time.

Luke/w 29

 

[anonymous]

to corey's mom, Corey may be caughing at night for several reasons that may relinquish during the day. Asthma and reflux cause bronchospasm that in turn cause coughing. If you have any questions e mail me, lukembarrt@yahoo.com


luke

 

[anonymous]

PFT s are bulls**t. They re only a mechanism with which doctors/consultants chart your demise.

 

[anonymous]

I'm glad some other people have experienced these issues. My hubby and I always joke that if I'm feeling really rough then my lung function will be good and if I feel good then it will be down! It can be frustrating though, especially as I sometimes feel that the doctors might think I'm making it up when I tell then I'm feeling worse and then the results come back higher than last time!

Incidently, in the US do you use the small electronic machines or the bigger Spirometry machines (with a thing that draws a curve on a bit of paper as you blow out)? I go to two clinics here in the UK and each uses a different type. I always seem to have higher results on the manual type machines compared to the electronic ones. Anyone else found this?

Emmie (30 yrs young from the UK)

 

[shamrock]

My pfts are at their best, 40% and yet i am the regional swimming champion in my age group! Yes, that makes a LOT of sense!

 

[shamrock]

Oh and I also hate the way when I'm feeling really lousy and then my pfts are good, I always feel the docs must think that I make it up!

 

[anonymous]

Hi!
WOW! Sounds just like me, and I'm glad I'm not the only one.

Usually, when I see my numbers, even if I didn't FEEL that bad before doing pfts, I will then feel crummier just because of that d*m* number! Or, if I see a high number unexpectedly, I will all of a sudden start thinking, "oh, so i'm not sick afterall!"

Anyway, I agree that psychology has alot to do with it... I've had anxiety attacks nearly every single time I do pfts cause I feel so much of my future (and current) health relies on them. I mean, I've thought of having a baby and all the docs say if your fvc is at or lower than this (magic number), don't have a baby, and if your fev1 is lower than this than don't have a baby... not that THAT's any pressure!

Anyway, even though I think they're kinda a joke, I can't quite get my mind around that, and I still seem to base how I'm feeling on pft's rather than the other way around! My docs are really supportive of whatever I want to do regardless of pfts, so I'm lucky that way. They base more on how I FEEL. Usually, when they come in after I've done a particularily shocking pft, they'll ask how I'm feeling and I'll respond, "Well, not too good, I guess! OR Really good, I guess!"

And, for the posted who is the swim champ with 40% fev1.... you inspire me!!!!!

Sonia
27 w/CF

 

[anonymous]

Hey guys,
It's important to remember that PFTs indicate what your lungs are doing on that particular day and are not meant to be a barameter for how you feel. The FEV1 measures the amount of air that you first push out against what is predicted for your weight, age and height and comes up with a percent.

There are alot of other things measured on a PFT. It also measures how much air is RETAINED in your lungs after you exhale. It gets trapped because of inflamation and mucus. My last PFT showed that I was retaining 234% of my prediction!!

Debbie
23 w/ CF

 

[Emily65Roses]

Oh I know they're not exact. I know it depends on the day and all that. It just seems like the doctors treat PFTs like they're an exact measurement of how you're doing and it tends to annoy me. Haha. If my PFTs are good and I say I'm not feeling well, I swear they think I'm being neurotic.

 

[Magerly111]

I agree with Debbie in that the numbers account for different aspects of how your lungs work. I was actually going to point that out until I read her post lol. But with respect to this thread, I'll have to agree that PFT's have a weird way of working....

In my latest experience, I was in the hospital this past May. I wasn't in there for low PFT's, or bad coughing, or feeling tired, etc...for me that's never really been the case...it's always my damn x-ray. But anyway, after being in the hospital for 2 weeks, my PFT's stayed exactly the same as before going in, if anything, they each went up like maybe 2 points....not a big deal. So I get out of there...and I slack off a bit on my meds. I go back for my one month follow-up, and my PFT's sky-rocketed to the highest they've ever been...and I honestly wasn't even really doing anything! They wound up being like 5-10 points higher than when I was in the hospital...

So I go back 3 months later, and of course they are back to the normal, not high anymore..and my doctor was worried. I don't get it. I've never been that high in my life, until that one time, when I wasn't even really doing my meds. And now he expects me to get up that high again...and I don't even know how it happened! But everytime I go, I think they're ok, cuz they're normal, and not much changes..and then my dr. compares to that one flippin time....grrrr. lol. Boo to PFT's.

 

[anonymous]

LUKE-
you mentioned that you shouldnt do PFT's in the morning. I have ALWAYS thought this. Everyone at the hospital doesnt try to disuade me from doing them in the afternoon, but they sort of act as if it doesn't really matter...but to just "do what i feel comfortable with." During a recent cleanout I went in for PFT's arond 4:30 pm, after a full day of work where I had been up since 7am and walking around. My PFT's were the highest they had been in almost 2 years. I felt great,and it was in the middle of the cleanout, so I was psyched. When I went back at the end of the cleanout I went at 11am...having only woken up around 9. The numbers were much lower...but still higher than before the cleanout....Basically they were what they usually are when i finish a round of meds. I KNEW it was because of the time of day. I mean i could feel it in my head and chest and everything while i was doing the test. It occured to me too that my appointments are LITERALLY ALWAYS in the morning...its like the way my hospital does it. They always try to give me 9 ams and I say no way and try to get at least an 11.

Anyway, my question for you is, I know that my pft's are better in the afternoon, but what are the "number" of reasons to not do them in the morning that you were referring to earlier? i was wondering if there were other things other than just the seemingly obvious "having just woken up..etc." that would make the results much less.

As a side note, PFTS have become for me a huge source of anxiety mostly because they rarely ever seem to reflect how I feel, its like a horrible conflict of interests somehow because I am IN control of something, i.e., I take the breaths in and the breaths out...yet I have NO control over it really because the results almost always are not what I expect. And the technicians usually just irritate the hell out of me...trying to be so PC and not really commenting on anything.

One time my first try came out with an FEV1 of 25% and I laughed and said "ok that can't be right," and the stupid technician said "well, you're just warming up, you can talk to your doctor about the numbers later." Granted my pft's are pretty low, around 40%, but I mean c'mon I was feeling great and I am not an idiot...I knew my FEV1 wouldnt be 25%! The next one was of course, normal...as were the rest, and I was like 'can you erase that one please.?' anyway, that was just a little venting, sorry

Caitlin

 

[anonymous]

my docs insist on doing pfts at either 8 am or 10 am! ridiculous! i felt like crap the first time i did them with this clinic because i'd just gotten up and hadn't even had my "coughing fit" for the morning! urgh! my hubby's in the military, so we've been to a couple different clinics. my last one was awesome (and a military hospital) because they did the tests after 1:00.... my cf nurse even said, "no cfers get out of bed before noon, so we just stopped doing the clinics that early cause no one would come." well, duh! why can't all clinics figure that out? a cf newsletter i get did a study and found for the general public, as well as those of us with plumo. issues, late afternoon gives optimal numbers in pfts. the numbers often went up 15% just from doing them in the afternoon versus morning! crazy! i feel like when i tell people its too early to come in for clinic at 8 or 10 or whatever AM, they're thinking i'm just lazy and don't want to get up. what really gets me is that these nurses and docs that run these clinics know what we have to do just to get up and get ready in the morning (getting up at 6:00 am for the 8:00 appt), yet they CONTINUE to have them morning hours as though we're just anyone getting up for a full-time job. its very aggravating to me and pfts aside, i wish they'd change the whole clinic to later in the day!!!!
sonia<img src="i/expressions/face-icon-small-smile.gif" border="0">