FEV 1

Question

Dear experts,
at measuring of the lung function of my 9-year-old daughter (CF) there are mentioned 2 FEV1-values. FEV1, measured in D%(actual1/desired) as 26.8 and FEV1% VC MAX, measured in D%(actual1/desired) as 20.9. Which of the two values corresponds to the "classical" FEV1-value, that means to wich value I can be orientented towards?
Thanks and greetings

Answer

Hello,
results of the lung function test are not so easy to read for outsiders. But even for insiders, some abbreviations on results pose sometimes a riddle. Therefore my answer is also based on the assumption, to have understood correctly the by you copied abbreviations of the result sheet. You should assume, that FEV1, measured in D% (actual1/desired) is probably the value, which you are looking for. The FEV 1 (one second capacity) is the volume, which can be expired forcedly within one second after maximal inspiration. The measurement of FEV1 is a method, in order to reveal an obstructive disturbance of the lung function. The FEV1% VC MAX value is the Tiffenau-index, also a parameter of obstruction. The Tiffeneau-index is indicated in percentage of the inspiratory measured vital capacity or the one at forced expiration. The latter can only be used to describe and obstruction as long as the vital capacity is in the normal range. In case I do interpret the by you mentioned values correctly, than here it deals obviously already with the difference in percentage to the normal value of 100%. In that case we have to deal already with an obstruction in your daughter.
Yours sincerely,
Olaf Sommerburg.

21.04.2010