CT-head indication, results and patient outcomes
| Within 6 hours of head injury | Within 24 hours of head injury | P value | |
| Indication N/total N (non-missing data) (%) | |||
| GCS <13 on initial assessment | 2/127 (1.6) | 3/251 (1.2) | 0.76 |
| GCS <15 at 2 hours post-injury | 19/127 (14.9) | 31/251 (12.4) | 0.48 |
| Suspected open or depressed skull fracture | 10/127 (7.8) | 21/251 (8.4) | 0.87 |
| Any sign of BOS# | 4/127 (3.1) | 17/251 (6.8) | 0.14 |
| Post-traumatic seizure | 5/127 (3.8) | 9/251 (3.6) | 0.86 |
| Focal neurological deficit | 4/127 (3.1) | 8/251 (3.6) | 0.98 |
| More than one episode of vomiting since injury | 5/127 (3.8) | 13/251 (5.2) | 0.59 |
| Current anticoagulant treatment | 34/127 (26.8) | 66/251 (26.3) | 0.92 |
| Congenital or acquired bleeding disorder | 1/127 (0.8) | 3/251 (1.2) | 0.72 |
| Age >65 with any LOC since injury | 18/127 (14.1) | 37/251 (14.7) | 0.89 |
| Age >65 with any amnesia since injury | 17/127 (13.4) | 40/251 (15.9) | 0.68 |
| Dangerous mechanism with any LOC or amnesia since injury | 37/127 (29.1) | 49/251 (18.5) | 0.04* |
| More than 30 min of retrograde amnesia prior to injury | 10/127 (7.9) | 28/251 (19.5) | 0.32 |
| CT-head timing Hours (median (IQR) | |||
| Time between injury and CT-head scan performance | 3.8 (2.5–5.2) | 5.2 (3.5–7.5) | <0.01* |
| Time between ED arrival and CT-head scan performance | 2.3 (1.3–3.2) | 2.4 (1.4–4.2) | 0.06 |
| Time between CT-head request and CT performance | 1.2 (0.6–1.8) | 1.0 (0.6–1.7) | 0.78 |
| CT-head result N/total N (non-missing data) (%) | |||
| Positive (new acute traumatic pathology) | 16/133 (12.0) | 35/265 (13.2) | 0.88 |
| Negative | 117/133 (88.0) | 230/265 (86.8) | |
| Negative with orbital or facial fracture | 8/117 (6.9) | 18/230 (7.8) | 0.76 |
| SAH | 6/16 (37.5) | 13/35 (37.1) | 0.85 |
| SDH | 5/16 (35.7) | 14/35 (40.0) | 0.73 |
| EDH | 0 | 0 | 0 |
| Contusion | 2/16 (12.5) | 8/35 (22.8) | 0.65 |
| Other ICHs | 7/16 (43.8) | 11/35 (31.4)) | 0.63 |
| BOS# | 4/16 (25.0) | 5/35 (14.3) | 0.49 |
| Other skull fractures | 7/16 (43.8) | 10/35 (28.5) | 0.50 |
| Neurosurgery consult N/total N (non-missing data) (%) | |||
| Clinical review performed | 8/133 (6.0) | 15/265 (5.7) | <0.001* |
| Telephone advice received | 8/133 (6.0) | 18/265 (6.8) | |
| Not consulted | 117/133 (88.0) | 232/265 (87.5) | |
| Neurosurgery required | 0 | 0 | |
| Outcome N/total N (non-missing data) (%) | |||
| Discharged from ED | 76/133 (57.1) | 132/265 (49.8) | <0.001* |
| Admitted to ED observation unit | 18/133 (13.5) | 60/265 (22.6) | <0.001* |
| Admitted to neurosurgery | 5/133 (3.8) | 11/265 (8.3) | |
| Admitted to other surgical wards | 20/133 (15.0) | 25/265 (9.4) | |
| Admitted to other medical wards | 13/133 (9.8) | 36/265 (27.3) | |
| ED length of stay (LOS) | |||
| Hours, median (IQR) | 5.3 (3.5–7.0) | 6.0 (4.2–7.9) | 0.02* |
| Within 6-hour LOS target, % (95% CI) | 65.0 (47.3 to 82.7) | 49.7 (39.3 to 60.1) |
*Results were considered significant if p value was <0.05.
BOS#, base of skull fracture; EDH, extradural haemorrhage; ICH, intracranial haemorrhage; LOC, loss of consciousness; SAH, subarachnoid haemorrhage; SDH, subdural haemorrhage.