Current primary investigation of choice for the detection of acute clinically important brain injuries is CT imaging of the head.
For adults who have sustained a head injury and have any of the following risk factors, perform a CT head scan within 1 hour of the risk factor being identified:
With respect to CT scan for an adult with a head injury:
- adult patients who have sustained a head injury and present with any one of the risk factors outlined should have CT scanning of the head requested immediately
- risk factors suggesting need for immediate CT scan
- GCS less than 13 on initial assessment in the emergency department
- GCS less than 15 at 2 hours after the injury on assessment in the emergency department
- suspected open or depressed skull fracture
- any sign of basal skull fracture (haemotympanum, 'panda' eyes, cerebrospinal fluid leakage from the ear or nose, Battle's sign)
- post-traumatic seizure
- focal neurological deficit
- more than one episode of vomiting
- for people 16 and over who have had some loss of consciousness or amnesia since the injury, do a CT head scan within 8 hours of the head injury, or within the hour in someone presenting more than 8 hours after the injury, if they have any of these risk factors:
- age 65 or over
- any current bleeding or clotting disorders
- dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of more than 1 m or 5 stairs)
- more than 30 minutes' retrograde amnesia of events immediately before the head injury
- CT should also be requested immediately in patients with any of the risk factors outlined below, provided they have experienced some loss of consciousness or amnesia since the injury
- risk factors for immediate CT scan if patient has experienced some loss of consciousness
- age 65 years or older
- coagulopathy (history of bleeding, clotting disorder, current treatment with warfarin)
- dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of greater than 1 m or five stairs)
- a provisional written radiology report should be made available within 1 hour of the scan being performed
For patients (adults and children) who have sustained a head injury with no other indications for a CT head scan and who are having anticoagulant treatment (1)
- perform a CT head scan within 8 hours of the injury or
- within the hour if they present more than 8 hours after the injury
- a provisional written radiology report should be made available within 1 hour of the scan being performed.
With respect to CT scan for a child (under 16 years of age) with a head injury:
- for people under 16 who have sustained a head injury, do a CT head scan within 1 hour of any of these risk factors being identified:
- suspicion of non-accidental injury
- post-traumatic seizure
- on initial emergency department assessment, a GCS score of less than 14 or, for babies under 1 year, a GCS score (paediatric) of less than 15
- at 2 hours after the injury, a GCS score of less than 15
- suspected open or depressed skull fracture, or tense fontanelle
- any sign of basal skull fracture (haemotympanum, 'panda' eyes, cerebrospinal fluid leakage from the ear or nose, Battle's sign)
- focal neurological deficit
- for babies under 1 year, a bruise, swelling or laceration of more than 5 cm on the head
- for people under 16 who have sustained a head injury and have more than 1 of these risk factors, do a CT head scan within 1 hour of the risk factors being identified:
- loss of consciousness lasting more than 5 minutes (witnessed)
- abnormal drowsiness
- 3 or more discrete episodes of vomiting
- dangerous mechanism of injury (high-speed road traffic accident as a pedestrian, cyclist or vehicle occupant, fall from a height of more than 3 m, high-speed injury from a projectile or other object)
- amnesia (anterograde or retrograde) lasting more than 5 minutes (it will not be possible to assess amnesia in children who are preverbal and is unlikely to be possible in children under 5)
- any current bleeding or clotting disorder
- observe people under 16 who have sustained a head injury but have only 1 of the risk factor for a minimum of 4 hours in hospital. If, during observation, any of the following risk factors are identified, do a CT head scan within 1 hour:
- a GCS score of less than 15
- further vomiting
- a further episode of abnormal drowsiness. If none of these risk factors occur during observation, use clinical judgement to determine whether a longer period of observation is needed
Reference:
- NICE (May 2023). Triage, assessment, investigation and early management of head injury in infants, children and adults