Ventilatory outcomes with normal lung compliance
| Standard versus upright resuscitator (normal compliance) | ||||||
|---|---|---|---|---|---|---|
| Main analysis: ventilations with <50 mL expiratory volume | Standard (n=4630)* | Upright (n=4744)* | ||||
| Mean (median) | Range of mean values among participants | Mean (median) | Range of mean values among participants | Mean difference (95% CI) | p Value† | |
| Expiratory volume <50 mL filter (mL) | 13.9 (15) | 2–27 | 15.5 (17) | 7–30 | 1.7 (0.7 to 2.8) | <0.001 |
| Mask leakage (%) | 57.6 (63.0) | 13–94 | 47.8 (44) | 13–88 | −10.1 (−14.8 to −5.3) | <0.001 |
| MAP (cm H2O) | 19.0 (20) | 11–27 | 19.9 (21) | 11–26 | 0.9 (0.3 to 1.5) | 0.003 |
| PIP | 35.2 (37) | 23–46 | 35.2 (36) | 22–45 | 0.0 (−1.1 to 1.0) | 0.93 |
| Sensitivity analysis: All ventilations included | Standard (n=4691) | Upright (n=4769) | ||||
| Expiratory volume (mL) | 14.7 (15) | 2.0–27 | 15.9 (17) | 7–30 | 1.3 (0.3 to 2.2) | 0.008 |
| Mask leakage (%) | 56.9 | 13–95 | 47.6 | 12–88 | −9.6 (−14.2 to −4.9) | <0.001 |
| MAP (cm H2O) | 18.9 (20) | 11–27 | 19.9 (21) | 11–26 | 1.0 (0.4 to 1.6) | 0.002 |
| PIP | 35.0 (37) | 6–56 | 35.1 (36) | 5–57 | 0.1 (−1.0 to 1.1) | 0.89 |
*n=number of ventilations per ventilator for all 82 students.
†Linear mixed-effects regression model.
MAP, mean airway pressure; PIP, peak inspiratory pressure.