Article Figures & Data
Figures
- Fig. 1.
Discrepancy between preset and actual airway pressures. A: inspiratory and expiratory airway pressure (Paw) medians of 5 respiratory cycles obtained with each individual mechanically assisted cough device (white symbols). The median values of the overall 15 measurements (black symbols) are also displayed for each type of device. Dashed lines indicate the ±4% tolerance limits according to the European Commission regulation for mechanical ventilators. B: inspiratory (TI) and expiratory (TE) time medians are shown for each device.
- Fig. 2.
Mechanically assisted cough device performance with varying mechanical properties and air leaks. A: Inspiratory airway pressure (Paw), tidal volume (VT), and time to reach 90% of preset inspiratory Paw (T90I) in different simulated conditions. B: Expiratory Paw, peak expiratory flow (PEF), and time to reach 90% of preset expiratory Paw (T90E) in different simulated conditions. Dashed lines indicate preset inspiratory (A) and expiratory (B) Paw. * P < .05, compliance of 40 mL/cm H2O and resistance of 10 cm H2O/L/s with air leaks (C40R10L) vs compliance of 40 mL/cm H2O and resistance of 10 cm H2O/L/s without air leaks (C40R10). † P < .05, compliance of 60 mL/cm H2O and resistance of 20 cm H2O/L/s with air leaks (C60R20L) vs compliance of 60 mL/cm H2O and resistance of 20 cm H2O/L/s without air leaks (C60R20). ‡ P < .05, C60R20 vs C40R10; § P < .05, C60R20L vs C40R10L. (For exact P values, see the supplementary materials at http://www.rcjournal.com.).
- Fig. 3.
Time for performing all the tests on all mechanically assisted cough devices by ICU physicians The graph shows the overall median time spent to accomplish all tasks by the product specialists (grey bar) compared with 10 ICU physicians (white bars). * P = .02, product specialists vs physicians.
- Fig. 4.
Determinants of peak expiratory flow (PEF), which is the strongest indicator of cough efficacy. The magnitude of PEF is directly influenced by the pressure applied to the airway opening (Paw) during the expiratory phase, the time to reach 90% of preset expiratory Paw (T90E), and the volume insufflated during the inspiratory phase (tidal volume [VT]), corresponding to the pre-tussive volume and resulting from the extent of the inspiratory Paw and the speed of achievement of the time to reach 90% of preset inspiratory Paw (T90I).
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