From: Effects of the components of positive airway pressure on work of breathing during bronchospasm
Methacholine (control) | Methacholine (study) | ||||
---|---|---|---|---|---|
Before | During | IPAP | EPAP | CPAP | |
Vt (ml) | 87 ± 17 | 139 ± 9* | 194 ± 9‡ | 175 ± 13‡ | 200 ± 13‡ |
Respiratory rate (breaths/min) | 40 ± 5 | 71 ± 8† | 56 ± 6‡ | 47 ± 6‡ | 59 ± 9‡ |
Ve (l/min) | 7.2 ± 0.9 | 10.1 ± 1.0* | 11.4 ± 1.1 | 9.3 ± 1.4 | 11.2 ± 1.6 |
Vinsp, peak (l/min) | 22 ± 2 | 24 ± 3 | 32 ± 3‡ | 32 ± 4‡ | 28 ± 3 |
Vt/Ti (ml/s) | 306 ± 29 | 368 ± 36 | 449 ± 40 | 446 ± 56 | 423 ± 54 |
Ti/Ttot | 0.39 ± 0.02 | 0.46 ± 0.01* | 0.41 ± 0.02 | 0.38 ± 0.04 | 0.43 ± 0.02 |
Vexp, peak (l/min) | 33 ± 2 | 27 ± 3 | 29 ± 3 | 28 ± 3 | 32 ± 3 |
Vt/Te (ml/s) | 313 ± 21 | 331 ± 30 | 359 ± 25 | 345 ± 33 | 368 ± 52 |
Te/Ttot | 0.42 ± 0.04 | 0.52 ± 0.01 | 0.53 ± 0.02 | 0.49 ± 0.05 | 0.52 ± 0.03 |
C dyn, lung (ml/cmH2O) | 70 ± 7 | 40 ± 4* | 28 ± 3‡ | 20 ± 2‡ | 43 ± 4 |
C dyn, cw (ml/cmH2O) | 124 ± 21 | 49 ± 7† | 61 ± 9 | 36 ± 6 | 79 ± 17 |
C dyn, rs (ml/cmH2O) | 232 ± 50 | 92 ± 10* | 91 ± 8 | 60 ± 8‡ | 105 ± 8 |
Ptp, exp (cmH2O) | -0.4 ± 0.6 | -0.8 ± 0.5 | 1.4 ± 0.9 | 5.0 ± 1.3‡ | 5.6 ± 1.1‡ |
Pabd, exp (cm H2O) | 4.5 ± 0.9 | 9.1 ± 1.8* | 10.0 ± 1.9 | 11.3 ± 1.5 | 11.0 ± 2.0 |
Ppl, exp (cmH2O) | -0.6 ± 0.1 | 2.2 ± 0.2 | 4.0 ± 0.2‡ | 4.9 ± 0.2‡ | 4.6 ± 0.3‡ |