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doyoudig
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Topics: 144
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05/14/07 - 10:54 AM

"fev1 of 1100 ml and ventilation perfusion scan indicates 60% of his pulmonary function comes from affected lung"

from this
1. What is the Normal FEV1
2. How do you know from the above info, what the FEV1 of the Normal lung is?

800 ml is needed to be left over after surgery, how do we calculate what is left over in the question above. Also Is it 800ml FEV1 in Total rite?

thx you for ur help!!

Justice
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05/14/07 - 11:13 AM

Normally FEV1 = 70-80% of the FVC
Lets assume that adult man's FVC is ~5000 ml (low border)... I do not know the exact FVC of this particular Pt, but there are predicted values, and for males they fall within 4500-6500 ml
If so, the Pt has quite severe COPD (<40% of FVC)
I do not know how calculate the residual function, but, if assume that 60% of the function comes from the affected lung, it will be only ~450 ml left (40% out of 1100 ml) after we remove the lung...
Hope I am correct

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Justice
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05/14/07 - 11:19 AM

Here is the link to a calculator:
http://www.cdc.gov/niosh/topics/spirometry/RefCal...
if we enter the Pts age (72) and assume his height as 180 cm, the Pts FVC should be 4.5L and FEV1 should be 3.29L
Thus, the Pt has only 33% of predicted function...
No surgery... It will kill him faster than cancer...

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doyoudig
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Topics: 144
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05/14/07 - 11:38 AM

thx you again fro a great explanation smiling face

Justice
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05/14/07 - 11:40 AM

doyoudig wrote:
thx you again fro a great explanation smiling face

You are ALWAYS welcome, colleague...
smiling face

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