Table 3—

Respiratory mechanics and inspiratory muscle function before and after 3 weeks of noninvasive mechanical ventilation (NIMV)

BaselineFinalMean (95% CI) change from baseline after NIMV
P0.1 cmH2O
 s-NIMV4.0±2.14.1±2.4
 NIMV4.2±1.93.1±1.3−1.1 (−1.6–−0.6)
P0.1/VT/tI cmH2O·L−1·s−1
 s-NIMV7.6±4.07.3±3.6
 NIMV7.8±2.84.9±1.4−2.9 (−3.8–−2.0)
EL,dyn cmH2O·L−1
 s-NIMV7.61±4.27.63±4.1
 NIMV8.98±3.74.79±1.7−4.18 (−5.6–−2.7)
RL cmH2O·L−1·s−1
 s-NIMV11.0±4.110.9±3.8
 NIMV8.9±4.96.4±3.1−2.5 (−4.0–−1.1)
PEEPi,dyn cmH2O
 s-NIMV2.55±1.12.69±1.2
 NIMV2.56±1.51.71±0.9−0.85 (−1.2–−0.5)
PI cmH2O
 s-NIMV11.9±3.312.4±3.4
 NIMV11.4±3.08.7±2.2−2.7 (−3.8–−1.5)
PI,max cmH2O
 s-NIMV59±1163±12
 NIMV55±1563±168 (4–12)
PI/PI,max
 s-NIMV0.20±0.060.20±0.06
 NIMV0.22±0.070.14±0.04−0.08 (−0.10–−0.04)
TTI
 s-NIMV0.065±0.020.064±0.02
 NIMV0.072±0.030.048±0.02−0.024 (−0.03–−0.02)
Pdi,max cmH2O
 s-NIMV79±2382±21
 NIMV66±1777±1811 (5–17)
TTdi
 s-NIMV0.044±0.010.040±0.01
 NIMV0.050±0.020.040±0.02−0.01 (−0.018–−0.001)
  • CI: confidence interval

  • P0.1: mouth occlusion pressure 100 ms after onset of inspiratory effort

  • s-NIMV: sham NIMV

  • P0.1/VT/tI: effective respiratory impedance

  • EL,dyn: dynamic lung elastance

  • RL: inspiratory lung resistance

  • PEEPi,dyn: intrinsic positive end-expiratory pressure

  • PI: mean inspiratory pressure swing

  • PI,max: maximal inspiratory pressure

  • TTI: tension/time index of the inspiratory muscles

  • Pdi,max: maximal transdiaphragmatic pressure

  • TTdi: tension/time index of the diaphragm

  • Analysis of covariance: : p<0.001