Figure 4.
Multiple breath washout and forced oscillatory mechanics. Measurements of (A) functional residual capacity (FRC) and (B) lung clearance index (LCI) were derived from multiple breath washouts using approximately 4% SF6 as the tracer gas. The higher LCI in the constant pressure group (p = 0.022) implies more inhomogeneous ventilation. The low-frequency forced oscillation technique was used to obtain partitioned measurements of the airway and tissue mechanics, including (C) airway resistance (Raw), (D) lower respiratory system tissue damping (tissue resistance, Glrs), and (E) lower respiratory system tissue compliance (Clrs). There was a trend to increased compliance in the bubble CPAP group.