Table 1.
Baseline characteristics and outcomes between patients with treatment failure and treatment success
| Variable | Treatment failure (n = 20) | Treatment success (n = 51) | p |
|---|---|---|---|
| Age—years | 46 (40–53) | 40 (35–45) | 0.01 |
| Female sex—no. (%) | 7 (35) | 21 (41) | 0.63 |
| Body mass index†—kg/m2 | 30.9 (28.7–32.6) | 30.4 (29.2–32.3) | 0.81 |
| Days from COVID confirmation | 4.0 (2.5–6.0) | 3.0 (2.0–4.0) | 0.07 |
| Comorbidities—no. (%) | |||
| Pulmonary disease | 3 (15) | 1 (2) | 0.06 |
| Chronic kidney disease | 3 (15) | 2 (4) | 0.10 |
| Diabetes | 3 (15) | 3 (6) | 0.21 |
| Hypertension | 4 (20) | 3 (6) | 0.07 |
| Cardiovascular disease | 0 | 5 (10) | 0.31 |
| Time from HFNC to APP initiation—hours | 6.0 (5.0–7.0) | 6.2 (5.0–7.8) | 0.27 |
| Before the first APP session | |||
| Heart rate—beats/min | 91 (82–99) | 97 (87–105) | 0.29 |
| Respiratory rate—breaths/min | 20 (18–23) | 20 (18–22) | 0.81 |
| Mean arterial pressure—mmHg | 85 (76–89) | 82 (76–87) | 0.30 |
| SpO2—% | 93 (91–96) | 94 (92–97) | 0.31 |
| HFNC flow settings—L/min* | 40 (40–40) | 40 (40–40) | 0.51 |
| FIO2 | 1.0 (0.8–1.0) | 0.9 (0.8–0.9) | 0.28 |
| SpO2:FIO2 | 107 (101–121) | 92 (92–118) | 0.09 |
| ROX index | 5.2 (4.3–6.2) | 5.5 (4.7–6.6) | 0.50 |
| LUS score | 20 (18–24) | 20 (19–23) | 0.74 |
| Management | |||
| Mean daily APP duration at first 3 days—hr/day | 9.8 (8.9–12.1) | 11.7 (8.7–16.5) | 0.18 |
| Dexamethasone—no. (%) | 20 (100) | 51 (100) | 1.0 |
| IL-6 modulators—no. (%) | 4 (20) | 6 (12) | 0.45 |
| Outcomes | |||
| ICU length of stay—days | 13 (9–16) | 7 (6–9) | 0.02 |
| Hospital length of stay—days | 19 (13–24) | 11 (9–12) | < 0.001 |
| Mortality—no. (%) | 8 (40) | 0 | < 0.001 |
Medians with interquartile ranges are in parentheses. APP awake prone positioning; HFNC high-flow nasal cannula; SpO2 saturation of pulse oximetry; FIO2 fraction of inspired oxygen; ROX SpO2:FIO2/respiratory rate
†Body-mass index is the weight in kilograms divided by the square of the height in meters
*HFNC was provided using Precision Flow Hi-VNI™ (Vapotherm, Exeter, NH) with maximum flow of 40 L/min