Univariate analyses: factors of the presentation and their association with outcome at 120 days (n=377)
| Outcome | OR (95% CI) for death | p-value | ||
| Dead | Discharged | |||
| Mechanically ventilated at any time (of those eligible) (n=315) | 160/161 (99.8) | 81/154 (52.6) | 144.2 (19.7–1056) | <0.001 |
| Respiratory support at time of diagnosis (n=375) | ||||
| Oxygen | 24/199 (12.1) | 44/176 (25.0) | Reference | |
| HFNO | 4/199 (2.0) | 6/176 (3.4) | 1.2 (0.3–4.8) | 0.77 |
| CPAP | 55/199 (27.6) | 70/176 (39.8) | 1.4 (0.8–2.7) | 0.24 |
| Mechanical ventilation | 116/199 (58.3) | 56/176 (31.8) | 3.8 (2.1–6.9) | <0.001 |
| Age (years) | 62.1±11.4 | 55.8±13.1 | <0.001 | |
| Subcutaneous emphysema | 167/200 (83.5) | 113/177 (63.8) | 2.9 (1.8–4.6) | <0.001 |
| Ischaemic heart disease or left ventricular systolic dysfunction | 26/200 (13.0) | 7/177 (4.0) | 3.6 (1.5–8.6) | <0.01 |
| Hypertension | 76/200 (38.0) | 46/177 (26.0) | 1.9 (1.2–2.9) | 0.01 |
| Diabetes mellitus | 53/200 (26.5) | 28/177 (15.8) | 1.9 (1.2–3.2) | 0.01 |
| Radiographic progression of pneumomediastinum | 58/200 (29.0) | 31/177 (17.5) | 1.9 (1.2–3.2) | 0.01 |
| ECMO (of those eligible) (n=241) | 11/160 (6.9) | 13/81 (16.0) | 0.4 (0.2–0.9) | 0.03 |
| Male | 140/200 (70.0) | 137/177 (77.4) | 0.7 (0.4–1.1) | 0.11 |
| Chest pain at presentation (n=365) | 19/193 (9.8) | 26/172 (15.1) | 0.6 (0.3–1.2) | 0.13 |
| Chronic kidney disease | 11/200 (6.0) | 5/177 (2.8) | 1.7 (0.6–4.6) | 0.21 |
| Asthma | 43/200 (21.5) | 30/177 (16.9) | 1.3 (0.8–2.3) | 0.27 |
| Tension phenomena | 13/200 (6.5) | 7/177 (4.0) | 1.7 (0.7–4.3) | 0.28 |
| Obesity (BMI ≥35 kg·m−2) | 23/200 (11.5) | 17/177 (9.6) | 1.2 (0.6–0.4) | 0.55 |
| Pneumothorax (at anytime) | 84/200 (42.0) | 70/177 (39.5) | 1.1 (0.7–4.7) | 0.63 |
Data are presented as n/N (%) or mean±sd, unless otherwise stated. HFNO: high-flow nasal oxygen; CPAP: continuous positive airway pressure; ECMO: extracorporeal membrane oxygenation; BMI: body mass index.