What are our real PFT numbers

Asexyblond23

New member
Ok I have been at the same clinic for the past 6 years. We just moved and I went to do a PFT test at the local hospital pulmonary clinic. I freaked out, my FEV 25-75 was at 36%. I have never been lower then 55 in my life. Also all my other numbers were lower too. I know im sick but this is really scary. I compared it to my last clinic and the predicted % they used was higher then the pred % that they used today. Which in my thinking would mean that if I was still at my old clinic I would have really bad numbers. Could you all look at what your PFT predictied % are and let me know. Im really nervous right now. Can this be right? Why are my small airways so low?
This is my old clinic in nashville:
Ref Pre %Ref
FVC 4.56 4.81 105
FEV1 3.843.46 90
25-75 3.922.50 64

New Clinic in Ft. Lewis
RefPre %Ref
FVC 4.15 4.58 111
FEV1 3.41 2.85 84
25-75 4.01 1.44 36
 

Asexyblond23

New member
Ok I have been at the same clinic for the past 6 years. We just moved and I went to do a PFT test at the local hospital pulmonary clinic. I freaked out, my FEV 25-75 was at 36%. I have never been lower then 55 in my life. Also all my other numbers were lower too. I know im sick but this is really scary. I compared it to my last clinic and the predicted % they used was higher then the pred % that they used today. Which in my thinking would mean that if I was still at my old clinic I would have really bad numbers. Could you all look at what your PFT predictied % are and let me know. Im really nervous right now. Can this be right? Why are my small airways so low?
This is my old clinic in nashville:
Ref Pre %Ref
FVC 4.56 4.81 105
FEV1 3.843.46 90
25-75 3.922.50 64

New Clinic in Ft. Lewis
RefPre %Ref
FVC 4.15 4.58 111
FEV1 3.41 2.85 84
25-75 4.01 1.44 36
 

Kristen

New member
Hmmm, that is weird. I'm pretty sure the numbers are based on Sex, Age, Weight, and Height, but I don't think they change that dramatically even if you do have a birthday or gain/lose weight. Could the new clinic have entered something wrong into the computer? I can't answer the question about the small airways - hopefully someone else will chime in on that. I happen to have an old PFT sheet next to me - it's from two years ago, though, but here are the numbers: For a 5'5", 150lb (I was pregnant at the time, so my weight was 25lbs higher than usual), 33 year old female:
Actual Pre %Ref FVC 3.83 3.82 100 FEV1 3.02 3.32 110 25-75 3.96 3.46 114
 

Kristen

New member
Hmmm, that is weird. I'm pretty sure the numbers are based on Sex, Age, Weight, and Height, but I don't think they change that dramatically even if you do have a birthday or gain/lose weight. Could the new clinic have entered something wrong into the computer? I can't answer the question about the small airways - hopefully someone else will chime in on that. I happen to have an old PFT sheet next to me - it's from two years ago, though, but here are the numbers: For a 5'5", 150lb (I was pregnant at the time, so my weight was 25lbs higher than usual), 33 year old female:
Actual Pre %Ref FVC 3.83 3.82 100 FEV1 3.02 3.32 110 25-75 3.96 3.46 114
 

Havoc

New member
There are many algorithms to determine normal value sets for PFTs (Polgar, Morris, Knudson, NHANES III, etc.) If your clinics use different sets, you will have varying results (the set used should be listed on the PFT report). This is why it's important to understand and be able to interpret your PFT's. Looking at % predicted is probably the worst way to benchmark yourself.

Looking at your PFT, you've got a pretty decent FEV1, but your small airways are either inflamed or obstructed.
 

Havoc

New member
There are many algorithms to determine normal value sets for PFTs (Polgar, Morris, Knudson, NHANES III, etc.) If your clinics use different sets, you will have varying results (the set used should be listed on the PFT report). This is why it's important to understand and be able to interpret your PFT's. Looking at % predicted is probably the worst way to benchmark yourself.

Looking at your PFT, you've got a pretty decent FEV1, but your small airways are either inflamed or obstructed.
 

Tisha

New member
I have seen a big difference in "percentage" from children's clinic to adult's, and also between machines/hospitals/countries (I've moved around quite a bit). The explanation is they might be using different parameters. What is a "holy value" to trust is the actual liters you are blowing. I any case, I don't think you should freak out because if you look, 3.92 and 4.01 it's nearly the same! Only the parameters used to compare are different, that's why you get a different percentage (if "ref" is reference value, your value, and "pre" is the predicted value - I hadn't seen it written like this before)
 

Tisha

New member
I have seen a big difference in "percentage" from children's clinic to adult's, and also between machines/hospitals/countries (I've moved around quite a bit). The explanation is they might be using different parameters. What is a "holy value" to trust is the actual liters you are blowing. I any case, I don't think you should freak out because if you look, 3.92 and 4.01 it's nearly the same! Only the parameters used to compare are different, that's why you get a different percentage (if "ref" is reference value, your value, and "pre" is the predicted value - I hadn't seen it written like this before)
 

rubyroselee

New member
Hi Alisha,

I have this problem right now too between two clinics and it freaks me out. At my Cleveland clinic, I sit around 85% FEV1. Since I've been living out East and going to a clinic here in Boston, my FEV1 is more at like a 95%. I have even gone back to the Cleveland clinic about once a year, and it still shows in the 80's when in Boston it shows the 90's. My small airways are similar - about 10% different.

My MDs don't really have an explanation other than they must be calculating it slightly differently. So my Cleveland MD said he would do a lung CT at my next visit to see if my lungs look more like an 80 or more like a 90.

So, I feel your pain - it's frustrating that different clinics show different numbers.
 

rubyroselee

New member
Hi Alisha,

I have this problem right now too between two clinics and it freaks me out. At my Cleveland clinic, I sit around 85% FEV1. Since I've been living out East and going to a clinic here in Boston, my FEV1 is more at like a 95%. I have even gone back to the Cleveland clinic about once a year, and it still shows in the 80's when in Boston it shows the 90's. My small airways are similar - about 10% different.

My MDs don't really have an explanation other than they must be calculating it slightly differently. So my Cleveland MD said he would do a lung CT at my next visit to see if my lungs look more like an 80 or more like a 90.

So, I feel your pain - it's frustrating that different clinics show different numbers.
 
K

katethekid

Guest
Not that I know a whole lot about what these numbers mean, but I'm learning. From what I can tell my airway is smaller than it should be which would explain why sometimes I feel like I'm trying to breathe through a straw. My advice is don't panic just yet, wait to see how you fair during your next PFT at the same clinic then compare them. Here are my latest PFT scores: FVC 3.11 91%FEV1 2.36 79%FEF25-75 1.94 54%
 
K

katethekid

Guest
Not that I know a whole lot about what these numbers mean, but I'm learning. From what I can tell my airway is smaller than it should be which would explain why sometimes I feel like I'm trying to breathe through a straw. My advice is don't panic just yet, wait to see how you fair during your next PFT at the same clinic then compare them. Here are my latest PFT scores: FVC 3.11 91%FEV1 2.36 79%FEF25-75 1.94 54%
 
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