Table 2.
Baseline patient characteristics
| Variablea | Total (n = 369) | Discharged (n = 274) | Admitted (n = 95) |
|---|---|---|---|
| Age, mean ± SD | 56.3 ± 19.5 | 52 ± 18.1 | 69 ± 17.6 |
| Sex, n (%) | |||
| Female | 149 (40.4) | 112 (40.9) | 37 (38.9) |
| Male | 220 (59.6) | 162 (59.1) | 58 (61.1) |
| Injury mechanism, n (%) | |||
| Falling to the same level | 199 (53.9) | 151 (55.1) | 48 (50.5) |
| Falling to a lower level | 63 (17.1) | 38 (13.9) | 25 (26.3) |
| Direct chest trauma | 19 (5.1) | 17 (6.2) | 2 (2.1) |
| Assault | 21 (5.7) | 19 (6.9) | 2 (2.1) |
| Sporting accident | 18 (4.9) | 18 (6.6) | 0 |
| Road traffic accident | 47 (12.7) | 31 (11.3) | 16 (16.8) |
| Car | 20 (5.4) | 12 (4.4) | 8 (8.4) |
| Motorbike | 6 (1.6) | 3 (1.1) | 3 (3.2) |
| Bike | 19 (5.1) | 15 (5.5) | 4 (4.2) |
| Pedestrian | 2 (0.5) | 1 (0.4) | 1 (1.1) |
| Unknown mechanism | 2 (0.5) | 0 | 2 (2.1) |
| Isolated chest trauma, n (%) | 319 (86.4) | 260 (94.9) | 59 (62.1) |
| Other injury, n (%) | 50 (13.6) | 14 (5.1) | 36 (37.9) |
| Head | 7 (1.9) | 0 | 7 (7.4) |
| Abdomen | 2 (0.5) | 0 | 2 (2.1) |
| Spinal | 13 (3.5) | 3 (1.1) | 10 (10.5) |
| Pelvic | 5 (1.4) | 0 | 5 (5.3) |
| Limbs | 35 (9.5) | 11 (4) | 24 (25.3) |
| Anticoagulation, n (%) | 27 (7.3) | 9 (3.3) | 18 (18.9) |
| Chronic lung disease, n (%) | 30 (8.1) | 11 (4.0) | 19 (20.0) |
| Patients with rib fractures, n (%) | 126 (34.1) | 41 (15.0) | 85 (89.5) |
| Number of rib fractures, mean ± SD | 1.1 ± 1.9 | 1.6 ± 1.5 | 3.2 ± 2.3 |
| SpO2, mean ± SD | 96.9 ± 3.1 | 97.7 ± 1.5 | 94.6 ± 4.6 |
| 95–100, n (%) | 284 (77.0) | 228 (83.2) | 56 (58.9) |
| 90–94, n (%) | 36 (9.8) | 7 (2.6) | 29 (30.5) |
| 85–89, n (%) | 5 (1.4) | 0 | 5 (5.3) |
| 80–84, n (%) | 5 (1.4) | 0 | 5 (5.3) |
| Unknown, n (%) | 39 (10.6) | 39 (14.2) | 0 |
| SpO2 on RA, n (%) | 357 (96.7) | 274 (100) | 83 (87.4) |
| SpO2 on O2, n (%) | 12 (3.3) | 0 | 12 (12.6) |
| Sternal fracture, n (%) | 16 (4.3) | 8 (2.9) | 8 (8.4) |
| Flail chest, n (%) | 9 (2.4) | 1 (0.4) | 8 (8.4) |
| First 4 rib fractures, n (%) | 34 (9.2) | 6 (2.2) | 28 (29.5) |
| Respiratory rate, mean ± SD | 17.7 ± 3.8 | 16.8 ± 2.0 | 20.1 ± 5.1 |
| Comorbidities | |||
| DM, n (%) | 32 (8.7) | 18 (6.6) | 14 (14.7) |
| IHD, n (%) | 27 (7.3) | 16 (5.8) | 11 (11.6) |
| Asthma, n (%) | 23 (6.2) | 18 (6.6) | 5 (5.3) |
| Alcohol dependence, n (%) | 20 (5.4) | 8 (2.9) | 12 (12.6) |
| Psychiatric disorder, n (%) | 14 (3.8) | 11 (4.0) | 3 (3.2) |
| CKD, n (%) | 12 (3.3) | 3 (1.1) | 9 (9.5) |
| Active cancer, n (%) | 12 (3.3) | 5 (1.8) | 7 (7.4) |
| Dementia, n (%) | 12 (3.3) | 2 (0.7) | 10 (10.5) |
| Drug addiction, n (%) | 10 (2.7) | 6 (2.2) | 4 (4.2) |
| Cirrhosis, n (%) | 4 (1.1) | 3 (1.1) | 1 (1.1) |
aSpO2 oxygen saturation level, RA room air, O2 oxygen, DM diabetes mellitus, IHD ischaemic heart disease, CKD chronic kidney disease