Table 3.
Comparisons between spontaneous and resistive breathing
| Spontaneous breathing | Resistive breathing | p-value | |
|---|---|---|---|
| Basic respiratory parameters | |||
| RR, breaths/min | 27 (± 9.29) | 29.3 (± 9.15) | 0.01 |
| Vt, ml | 354.08 (± 180.44) | 243.41 (± 138.06) | < 0.001 |
| RSBI, breaths/min/L | 80.7 (47.16, 131.4) | 146.8 (79.34, 201.9) | < 0.001 |
| Ti, s | 0.8 (0.7, 1) | 0.8 (0.7, 1) | 0.826 |
| Texp, s | 1.53 (1.04, 1.96) | 1.14 (1.02, 1.44) | < 0.001 |
| Ti/Ttot | 0.36 (± 0.1) | 0.41 (0.11) | 0.005 |
| MIF, ml/s | 369.3 (284.68, 485.64) | 265.2 (154.57, 343.67) | < 0.001 |
| Diaphragmatic ultrasound | |||
| Dex, cm | 1.05 (0.7, 1.59) | 1.44 (0.89, 1.96) | 0.002 |
| Tfdi | 0.46 (± 0.2) | 0.55 (± 0.32) | 0.019 |
| Manometric indices | |||
| ΔPes, cmH2O | 6.8 (4.6–10.23) | 11.87 (7.86, 18.32) | < 0.001 |
| ΔPdi, cmH2O | 7.94 (± 3.81) | 10.89 (± 6.42) | < 0.001 |
| PTPes, cmH2O*s | 97.52 (55.96–179.87) | 181.10 (108.34, 311.7) | < 0.001 |
RR = respiratory rate, Vt = tidal volume, Ti = inspiratory time, Ti/Ttot = the ratio of inspiratory time to respiratory time, MIF = mean inspiratory flow, Dex = diaphragmatic excursion, Tfdi = diaphragmatic thickening fraction, ΔPes = esophageal pressure swings, ΔPdi = transdiaphragmatic pressure swings, PTPes = pressure–time product of the esophageal pressure. Table entries represent means (± SD), medians (25th, 75th interquartile range. Comparisons between groups were performed with Student’s t test or Mann–Whitney U test respectively. P values represent the difference between spontaneous and resistive breathing