TABLE 4.
Comparison between physiological effects of face mask (FM) and noninvasive ventilation (NIV)
| FM | NIV | NIV–FM | ||
| Median (IQR) | Median (IQR) | Median (95% CI) | p-value# | |
| VT global (units) | 2402 (1641–3050) | 3161 (1884–3805) | 606.0 (441.5–792.0) | <0.0001 |
| VT ROI1 (units) | 593 (566–737) | 887 (657–1033) | 182.5 (97.0–269.0) | 0.001 |
| VT ROI2 (units) | 479 (321–683) | 686 (413–925) | 182.5 (122.5–251.0) | <0.0001 |
| VT ROI3 (units) | 649 (427–836) | 743 (498–1008) | 132.5 (73.5–194.5) | 0.0002 |
| VT ROI4 (units) | 383 (259–772) | 444 (318–861) | 98.5 (17.0–178.0) | 0.02 |
| VT consolidation (units) | 593 (160–819) | 778 (338–1002) | 151.0 (58.0–215.5) | 0.009 |
| EELI global (units) | 1999 (764–2779) | 4083 (2928–5134) | 1810.5 (857.0–2646.0) | 0.001 |
| EELI ROI1 (units) | 327 (115–618) | 842 (646–1144) | 518.0 (315.5–779.0) | <0.0001 |
| EELI ROI2 (units) | 361 (135–880) | 960 (469–1406) | 457.5 (130.0–818.0) | 0.009 |
| EELI ROI3 (units) | 317 (144–567) | 767 (336–1124) | 414.0 (76.0–678.5) | 0.02 |
| EELI ROI4 (units) | 382 (115–572) | 846 (488–971) | 374.0 (108.0–670.5) | 0.01 |
| EELI consolidation (units) | 562 (160–776) | 899 (767–1144) | 404.5 (59.0–718.0) | 0.02 |
| Respiratory rate (breaths·min −1 ) | 26 (25–30) | 24 (22–27) | −2 (−6–2) | 0.6 |
| SpO2/FiO2 ratio | 152 (145–152) | 167 (143–200) | 21.0 (2.5–50.0) | 0.03 |
| SpO2 (%) | 100 (96–100) | 100 (98–100) | 0 (0–2) | 0.3 |
| Heart rate (beats·min −1 ) | 85 (79–103) | 84 (68–98) | −1 (−3–5) | 0.8 |
| SBP (mmHg) | 122 (109–129) | 119 (108–131) | −1 (−7–11) | 1.0 |
| MAP (mmHg) | 84 (77–91) | 80 ( 76–89) | −1 (−2–4) | 1.0 |
| Dyspnoea score (0–10) | 2 (0–5) | 5 (0–5) | 0 (−1–3) | 0.5 |
| Patient comfort score (0–10) | 8 (5–10) | 4 (2–5) | −3 (−5− −1) | 0.001 |
Bold type reprensents statistical significance. IQR: interquartile range; VT: tidal volume variation; ROI: region of interest; EELI: end-expiratory lung impedance; SpO2: pulse oxygen saturation; FiO2: inspiratory oxygen fraction; SBP: systolic blood pressure; MAP: mean arterial pressure. #: Wilcoxon signed rank test.