Figure 4
From: Detection of air trapping in chronic obstructive pulmonary disease by low frequency ultrasound
Lung function and ultrasound before and after inhalation of Salbutamol. a) FEV1 increased significantly in healthy and COPD subjects (healthy: p = 0.01, GOLD 1: p = 0.011, GOLD 2: p = 0.015, GOLD 3: p = 0.012). b) Airway resistance decreased significantly in healthy subjects (p = 0.0002) as well as in GOLD stage 1 (p = 0.005) and GOLD stage 3 (p = 0.032). c) Residual volume decreased significantly in healthy subjects (p = 0.033) as well as in GOLD stage 1 (p = 0.016) and GOLD stage 3 (p = 0.02). d) There was no significant difference of frequency shift during non-forced maximum breathing in any group.