On restrictive ventilatory disorders
VC reduction 60% ≤ VC < 80% of the expected value Judged as mild
Expected value of 40%≤VC<60% Judged as moderate
VC < 40% of the expected value is considered severe
About obstructive ventilatory disorders
First look at the actual FEV1/FVC% measured value Less than 70% is obstructive ventilation disorder
If the measured FEV1/FVC% is greater than 70%, obstructive ventilation is basically not determined.
Classification of obstructive ventilatory disorder
90% ≤ FEV1 < 100% of the expected value Mild
60% ≤ FEV1<89% of the expected value is judged as moderate
FEV1<59% of the expected value is considered severe
If both of the above conditions are present, then it is a mixed ventilation disorder and the grade is towards severe.
Small airways can be determined according to MEF50 MEF25
60% ≤ MEF50 MEF25 < 80% of the expected value Mild
40% ≤ MEF50 MEF25 < 60% of the expected value Judged as moderate
MEF50 MEF25<40% of the expected value Judged as severe
Diffusion function
DLco should be greater than 80% of the expected value
60% ≤ DLco < 80% of the expected value Judged as mild
40% ≤ DLco < 60% of the expected value Judged as moderate
DLco < 40% of the expected value is considered severe
The specific clinical significance is described in the relevant books