Table 2.
Comparative analysis between COPD and control subjects considering the impedance in different phases of the ventilatory cycle.
| COPD | Control | p-value | |
| Zm (cmH2O\L\s) | 10.0±2.8 | 4.6±1.2 | 0.001 |
| Zi (cmH2O\L\s) | 9.0±2.5 | 4.4±1.2 | 0.001 |
| Ze (cmH2O\L\s) | 10.5±3.1 | 4.7±1.3 | 0.001 |
| Zbi (cmH2O\L\s) | 8.1±2.0 | 4.3±1.3 | 0.001 |
| Zbe (cmH2O\L\s) | 11.0±3.1 | 4.8±1.3 | 0.001 |
| Zpp (cmH2O\L\s) | 2.93±2.02 | 0.50±0.74 | 0.001 |
| ΔZrs (cmH2O\L\s) | 1.49±1.65 | 0.27±0.57 | 0.005 |
Zm – Mean impedance of the respiratory system; Zi – inspiratory impedance; Ze – expiratory impedance; Zbi – impedance at the beginning of inspiration; Zbe – impedance at the beginning of expiration. Zpp – peak-to-peak variation of the impedance; ΔZrs – variation of the mean impedance.