Total n=277 | Missing SI* n=15 | No SI n=116 | Any SI n=146 | P value† | |
Demographics | |||||
Age, median years (IQR) | 33 (23–51) | 15 | 32 (23–46) | 33 (23–53) | 0.66 |
Male n, (%) | 219 (79.1) | 11 | 101 (87.1) | 107 (73.3) | 0.009 |
Injury characteristics | |||||
Injury type, N (%) | |||||
Blunt | 275 (99.3) | 15 | 116 (100) | 144 (98.6) | 0.5 |
Mechanism of injury, N (%) | |||||
Motor vehicle/bike | 99 (35.8) | 4 | 39 (33.6) | 56 (38.4) | 0.43 |
Fall from <3 m | 48 (17.3) | 1 | 24 (20.7) | 23 (15.8) | 0.3 |
Fall from ≥3 m | 41 (14.8) | 4 | 13 (11.2) | 24 (16.4) | 0.28 |
Struck by vehicle | 35 (12.6) | 3 | 11 (9.5) | 21 (14.4) | 0.26 |
Assault | 18 (6.5) | 0 | 12 (10.4) | 6 (4.1) | 0.05 |
Pushbike | 14 (5.1) | 2 | 7 (6.0) | 5 (3.4) | 0.38 |
Other | 22 (7.9) | 1 | 10 (8.6) | 11 (7.5) | 0.82 |
GCS (highest), N (%) | |||||
3–8 | 176 (63.6) | 10 | 70 (60.3) | 96 (65.8) | 0.37 |
9–12 | 48 (17.3) | 1 | 27 (23.3) | 20 (13.7) | 0.04 |
13–15 | 53 (19.1) | 4 | 19 (16.4) | 30 (20.5) | 0.43 |
Pupillary response, N (%) | |||||
Both reactive | 185 (66.8) | 11 | 89 (76.7) | 85 (58.2) | 0.002 |
One unreactive | 37 (13.4) | 3 | 15 (12.9) | 19 (13.0) | 1.0 |
Both unreactive | 48 (17.3) | 1 | 11 (9.5) | 36 (24.7) | 0.002 |
Not stated | 7 (2.5) | 0 | 1 (0.9) | 6 (4.1) | 0.14 |
HAIS, N (%) | |||||
0–2 | 58 (20.9) | 1 | 29 (25.0) | 28 (19.2) | 0.26 |
3 | 58 (20.9) | 3 | 23 (19.8) | 32 (21.9) | 0.68 |
4 | 74 (26.7) | 9 | 30 (25.9) | 35 (24.0) | 0.73 |
5 | 71 (25.7) | 2 | 26 (22.4) | 43 (29.4) | 0.2 |
Unknown | 16 (5.8) | 0 | 8 (6.9) | 8 (5.5) | 0.8 |
Isolated TBI‡ | 105 (40.2) | 7 | 53 (49.1) | 45 (32.6) | 0.009 |
Polytrauma TBI‡ | 98 (37.5) | 7 | 26 (24.1) | 65 (47.1) | <0.001 |
ISS§, median (IQR) | 26 (17–34) | 15 | 21 (13–29) | 29 (21–38) | <0.001 |
ISS ≥25, n (%) | 148 (55.8) | 7 | 43 (39.8) | 98 (69.0) | <0.001 |
*Patients missing data on either prolonged hypotension OR prolonged hypoxia OR arrival end-tidal carbon dioxide <30 mm Hg.
†Mann-Whitney test used for continuous variables; Χ2 or Fisher’s exact test used for categorical variables.
‡Isolated TBI defined as a HAIS ≥3 with all other AIS <3; polytrauma TBI defined as a HAIS ≥3 with one other AIS ≥3.
§Twelve patients had missing ISS data.
AIS, Abbreviated Injury Scale; HAIS, 'Head' Abbreviated Injury Scale; ISS, Injury Severity Score; SI, secondary insult; TBI, traumatic brain injury.