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HELP READING PFT RESULTS

Seana30

New member
I am glad to report that Courtney's pulmo visit was GREAT.

I am still not quite understanding how to read her PFT results other than knowing that 100% is REALLY GOOD.

She also had her gastro appointment this week and the doc is very pleased with her weight gain. She is now 80 pounds.

I am going to post her PFT results if you all could explain to me what each one means.

THANKS

RESULTS PRED PRE %PRD

FVC (L) 3.13 3.31 106%

FEV1 (L) 2.98 3.09 104%

FEV1/FVC 0.86 0.93 109%

FEF25-75% 3.42 4.03 118%

PEFR (L/s) 6.67 6.01 90%

Seana
 

Emily65Roses

New member
I never much go by those last numbers myself, they are the percent predicted. It just means for someone her age, height, weight, blah blah, she's doing better than they expect. It doesn't mean any actual numbers. Just that for her, they expect number X and she's doing so well, she's at number X + some. It's a predictor of her health overall, and that she's doing well, but doesn't tell you her actual numbers. For me, I'm at like 94% predicted, but 73% FEV1. Just means that I'm doing well for 22 years old, but it doesn't mean I'm actually at 94%. You see what I'm saying?

The real numbers are the first column. Which means, I BELIEVE, she has an... 86% FEV1. Very good. The PFT sheets are still a little confusing to me too, so I may be off a bit. I know the first part is right, though. The thing about percent predicted. The 25-75% number is her small airways, just as an added piece of info.
 

EnergyGal

New member
Those numbers are outstanding. Does she have any lung damage from CF? It does not seem that way from her numbers. WOW
 

Seana30

New member
Risa,

We have been very lucky with Courtney when it comes to her lungs. She has only been hospitalized once for lung issues, and that was this past March.

Her main issues are digestive.

I try to keep a positive, but realistic attitude about it. We celebrate when she gets these kind of results, but know that this could possibly change as time passes.

I want Courtney to live a happy, full, positive life, but be realistic about her illness.

Seana

(sorry, didn't mean to start ranting about how I hope Courtney deals with all of this.....that was not the questioned you asked.....lol)
 

Seana30

New member
Emily,

Thank you for the explanation. I am still a bit confused, but I am going to print out your post and sit down with Courtney's results and see if I can figure it all out.

THANKS!

Seana
 

Emily65Roses

New member
I know I wasn't incredibly clear. Haha. I don't understand them 100% either, I'm hoping someone can clear it up more for you. The only thing I'm pretty sure of is the percent predicted and what it means. If you want me to take a stab at explaining that again, I can absolutely do that. The rest of it, like I said, I'm hoping someone else comes in and makes it clearer than I can. Hah.
 

cdale613

New member
Hi Seana,
Just to clarify... I think you're getting some misinformation from earlier responses. Column 1 is the predicted value, which is derived from "healthy" patients of your daughter's age, height, and weight. For example, the "predicted" FEV1 for Courntey based on other girls is 2.98 Liters. It is the denominator in determining your daughter's percentages. The second column are Courtney's results. Her FEV1 is 3.09 liters. This is the numerator. The third column is "percent of predicted." 3.09/2.98 = 103.6%. This means that Courntey's FEV1 is 103% of the predicted value, or 3% higher than the predicted value. As you probably know, FEV1 is the amount of air expelled in the first second. FVC is total capacity. FEV1/FVC is the % of total air expelled in the first second, and is different from the FEV1 number - one is a percent, one is volume. The "predicted" percent expelled in 1 second is 86%, Courntey's percent expelled in 1 second is 93%. The percent comparison here is less useful - percents of percents aren't very meaningful, but again, her numbers are above predicted.

Your daughter's numbers are fantastic, but remember that these are HER numbers, and should be compared to her past performance more than the predicted values. For example, if at her last visit her FEV1 was 3.39 liters, then that means her current results represent a 10% drop, which might be of concern. Just because she's above 100% of predicted doesn't mean that she's at her own 100%.

Hope this helps.

Chris

26 w/CF
 

Emily65Roses

New member
I can't tell if that's a male or female Chris, but s/he sounds like s/he knows what s/he's talking about, so I'd say what s/he said is probably right. Heh. It also happens to be much clearer than all the crap I said. <img src="i/expressions/face-icon-small-blush.gif" border="0">
 

LouLou

New member
actually weight doesn't effect the percentages. height does though. this may help you seana to understand it a bit better. imagine if courtney grew an inch between now and her next appt. but for whatever reason her lung capacity didn't show a change in greater capacity. This would have a negative effect on the percentage while her 'raw' score (currently 3.09) might not have gone down. It's not that she 'lost capacity' as the lower %ile might depict rather it's just not as high in the higher bracket. To add confusion once a set of lungs are full grown (adult) their is an expected rate of loss for even non-CFers so CF doctors don't like to look at percentages because who wants to look at data when they've 'pre-factored' in capacity loss. Loss on top of loss gets confusing.

now I don't understand what Em's trying to explain to you becuase as far as I know this is what this means:

FEV1 (L) 2.98 3.09 104%

2.98 is the volume predicted for someone her age and height.
3.09 is the actual volume she blew out in the 1st second of her test.
104% is the the percentage created by comparing her blow to the predicted blow. (actual number is 103.6% - the computer rounded it to 104%)

If someone else get's Emily's explanation I'd love to learn more about reading pft results.
 

anonymous

New member
I never had those numbers with my cf lungs when I was little. I think the highest I remember when I was seventeen was 2.50 and that was probably FVC because back then machines were not like today.
 

Emily65Roses

New member
I wouldn't go by me, it seems I was full of crap. Not on purpose, of course. I do know that the 25-75% number is your small airways, though. Heh. <img src="i/expressions/face-icon-small-confused.gif" border="0">
 

anonymous

New member
It is true that in the MAJORITY of formulas used to calculate the predicted amount weight is not used. However, it is used in a variety of the equations. It is important to note that the "healthy lungs" being compared to is not really a group of people that have been measured, but a value produced by an equation. Also, it is possible to have different doctors using different equations and get a change in your % that way. Your values produced should not be changed however, so that's an additional reason to pay attention to the actual values produced rather than the comparison statistics.
 
I

IG

Guest
Nice numbers...
<a target=_blank class=ftalternatingbarlinklarge href="http://en.wikipedia.org/wiki/Pulmonary_Function_Test#Explanation_of_Common_Test_Values_in_FVC_Tests
">http://en.wikipedia.org/wiki/P...t_Values_in_FVC_Tests
</a>
FVC: Forced Vital Capacity - This is the total amount of air that you can forcibly blow out after full inspiration, measured in liters.
FEV1: Forced Expiratory Volume...
page goes on to explain.. <img src="i/expressions/face-icon-small-smile.gif" border="0">
 

JustDucky

New member
Kudos for Courtney! Those numbers are awesome! She is doing better than her expected volumes...I see alot of 100%+ values in that last column which is great. As someone said, the first set of numbers are the expected values for her gender and height as another poster has detailed. The second set of numbers are what she actually did and the very last column are her percentages. Tell her to keep doing what she is doing (as well as you, you deserve a pat on the back too). Hugs to both of you, Jenn <img src="i/expressions/face-icon-small-smile.gif" border="0">
 

Seana30

New member
Thank you all so much for the info.

I actually understand what I am reading now!! Woohoo

I appreciate all of the help!

Seana
 
L

luke

Guest
Seana,

The only number that is not >100%(PEFR) doctors really only use to determine effort. Since courtney is only 13 I imagine she could do better than that with better emphasis on technique from the RT. Other than that her numbers are absolutely normal.

Luke, RRT
 
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