Table 3.
Ventilation parameters during study phases.
| Ventilation variable | ASV + FiO2 controller (n = 30) | ASV + Manual FiO2 (n = 30) | p1 |
|---|---|---|---|
| MinVent (l/min) | 2.9 (2.4–3.5) | 2.9 (2.4–3.4) | 0.642 |
| VT/IBW (ml/kg) | 7.5 (6.4–8.1) | 7.4 (6.3–8.4) | 0.19 |
| RR (b/min) | 29.3 (23.1–38.8) | 29.5 (24.3–35.9) | 0.257 |
| PetCO2 (mmHg) | 42 (33.4–50.3) | 42.8 (33.7–54.1) | 0.17 |
| PIP (cmH2O) | 20.2 (14–26.6) | 20 (15.4–25.5) | 0.719 |
| PEEP (cmH2O) | 5 (5–6.5) | 5 (5–6.5) | 1 |
| FiO2 (%) | 31.4 (25.1–44.1) | 36.5 (30–49) | <0.001 |
| FiO2 adjustment (n/2h) | 52 (11.8–67) | 1 (0–2) | <0.001 |
| Ti (s) | 0.7 (0.6–0.8) | 0.7 (0.6–0.8) | 0.234 |
| Te (s) | 1.3 (0.9–1.7) | 1.4 (0.9- 1.7) | 0.176 |
| SpO2 (%) | 96.2 (95.8–96.8) | 97 (95.2–97.6) | 0.245 |
| SpO2 DOT (%) | 96.4 (93.6–98.7) | 78.4 (51.4–98) | <0.001 |
| OI | 3.1 (2.4–6) | 3.5 (2.6–6.6) | <0.001 |
| S/F | 300.7 (210.8–382.2) | 254.1 (189.2–302.4) | <0.001 |
| TO2 (l/min) | 0.3 (0.1–0.7) | 0.5 (0.2–0.9) | <0.001 |
Data are expressed in median and interquartile range (25–75th) and compared between ASV+closed loop FiO2 controller and ASV+ Manuel FiO2 titration groups by Wilcoxon signed-rank test (p1).
ASV, Adaptive support ventilation; FiO2, fraction of inspired oxygen; VT, tidal volume expired; IBW, ideal body weight; RR, respiratory rate; PetCO2, end-tidal carbondioxide; PIP, peak inspiratory pressure; Ti, inspiratory time; Te, expiratory time; SpO2, peripheral oxygen saturation; SpO2DOT, peripheral oxygen saturation duration in optimal target; OI, oxygenation index; S/F, peripheral oxygen saturation to fraction of inspired oxygen ratio; TO2, therapeutic oxygen use.