| Individual
spirograms are "acceptable" if: |
| |
They
are free from artifacts |
| |
|
Cough
or glottis closure during the first second of exhalation |
|
Eary
termination or cutoff |
|
Variable
effort |
|
Leak |
|
Obstructed
mouthpiece |
|
| |
Have
good starts |
| |
|
Extrapolated
volume less than 5% of FVC or 0.15 L, whichever is greater;
OR |
|
Time-to-PEF
of less than 120 ms (optional until further information is available) |
|
| |
Have
a satisfactory exhalation |
| |
|
6 s of
exhalation and/or a plateau in the volume-time curve; OR |
|
Reasonable
duration or a plateau in the volume-time curve; OR |
|
If the
subject cannot or should not continue to exhale |
|
|
| After
3 acceptable spirograms have been obtained, apply the following tests: |
|
Are the two largest
FVC within 0.2 L of each other? |
|
Are the two largest
FEV1 within 0.2 L of each other? |
| If
both of these criteria are met, the test session may be concluded. |
| If
both of these criteria are not met, continue testing until: |
|
Both of the criteria
are met with analysis of additional acceptable spirograms; OR |
|
A total of eight
tests have been performed; OR |
|
The patient/subject
cannot or should not continue |
| Save
at a minimum the three best manuvers |
|