Table 4.
Diaphragm muscle fiber cross-sectional area and proportion with various modes of mechanical ventilation with and without applied positive end-expiratory airway pressure a
| Control | CPAP | CPAP-8 | AMV | AMV-8 | CMV | CMV-8 | |
|---|---|---|---|---|---|---|---|
| Fiber cross-sectional areas (μm2) | |||||||
| MyHCslow | 1,725 ± 80 | 1,581 ± 79 | 1,922 ± 146 | 1,778 ± 180 | 1,658 ± 150 | 1,404 ± 174 | 1,407 ± 60 |
| MyHCfast | 2,565 ± 214 | 2,478 ± 108 | 2,416 ± 113 | 2,606 ± 156 | 2,872 ± 193 | 2,016 ± 284 | 2,302 ± 143 |
| Fiber proportion (%) | |||||||
| MyHCslow | 44.8 ± 3.0 | 41.0 ± 4.8 | 36.3 ± 1.8 | 41.5 ± 3.7 | 45.9 ± 3.5 | 37.6 ± 2.5 | 39.1 ± 2.0 |
| MyHCfast | 55.2 ± 3.0 | 59.0 ± 4.8 | 63.7 ± 1.8 | 58.5 ± 3.7 | 54.1 ± 3.5 | 62.4 ± 2.5 | 60.9 ± 2.0 |
aValues ± SE (n = 4 animals in each group). AMV, Assist-control mechanical ventilation; CMV, Controlled mechanical ventilation (numerical value of 8 next to ventilatory mode denotes the set CPAP or PEEP of 8 cmH2O); CPAP, Continuous positive airway pressure; MyHC, Myosin heavy chain.