Mild traumatic brain injury

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

INITIAL

suspected traumatic brain injury (any severity)

1st line – stabilisation and supportive care

Back

1st line –

stabilisation and supportive care

Take an Airway, Breathing, Circulation (ABC) approach to assessing and stabilising any patient with a traumatic brain injury.[42]

If you suspect cervical spine injury, ensure full cervical spine immobilisation (before transfer of the patient to hospital, if presenting in the community).[42] See Acute Cervical Spine Trauma.

Manage pain effectively because it can lead to a rise in intracranial pressure.[42][52] Follow local protocols for pain management. Provide reassurance, splint limb fractures and catheterise a full bladder when needed.[42]

Practical tip

The diagnosis of mild traumatic brain injury (Glasgow Coma Scale [GCS] score 13-15) is clinical.[18] Selected patients (including those on anticoagulant treatment) must undergo a computed tomographic head scan to exclude an intracranial complication (e.g., bleed). See the Diagnosis section.

For the assessment of patients with moderate (GCS score 9-12) or severe (GCS score ≤8) traumatic brain injury, see Assessment of traumatic brain injury, acute.

ACUTE

confirmed mild traumatic brain injury: in hospital

admission indicated

1st line – observation and supportive care

Back

1st line –

observation and supportive care

Most patients with mild traumatic brain injury (TBI) do not require hospital admission. Admit patients with mild TBI, however, if any of the following is present:[42]

New, clinically significant abnormalities on imaging
Glasgow Coma Scale (GCS) score has not returned to 15; or a GCS score that has not returned to the pre-injury baseline after imaging, regardless of the imaging results [ Glasgow Coma Scale Opens in new window ]
There are indications for computed tomographic (CT) scanning but this cannot be done within the appropriate period (i.e., CT not available or patient not sufficiently co-operative to allow scanning)
Continuing worrying signs (e.g., persistent vomiting, severe headaches)
Other sources of concern (e.g., drug or alcohol intoxication, other injuries, shock, suspected non-accidental injury, meningism, cerebrospinal fluid leak).

Consider or suspect abuse, neglect or other safeguarding issues as a contributory factor to, or cause of, a head injury.[42]

Manage pain effectively because it can lead to a rise in intracranial pressure.[42] Provide reassurance, splint limb fractures and catheterise a full bladder when needed.[42] Follow local protocols for pain management.

Reassess the patient and consider an immediate CT scan if during observation there are any signs of neurological deterioration such as:[42]

Development of agitation or abnormal behaviour
A sustained (for at least 30 minutes) drop of 1 point in GCS score (give greater weight to a drop of 1 point in the motor response score of the GCS)
Any drop of ≥3 points in the eye-opening or verbal response scores of the GCS, or ≥2 points in the motor response score
Development of severe or increasing headache or persistent vomiting
New or evolving neurological symptoms or signs, such as pupil inequality or asymmetry of limb or facial movement.

A supervising doctor should conduct the appraisal.[42]

If after 24 hours of observation the patient has not achieved a GCS score of 15 and has had a normal CT scan, consider further CT scan or magnetic resonance imaging scanning and discuss with the radiology department.[42]

Practical tip

Discuss with a neurosurgeon any patient with any of the following (which by definition suggest the patient has a moderate or severe traumatic brain injury):[42]

New, surgically significant (as defined locally) abnormalities on imaging
Any of the following regardless of imaging results:
- Persisting coma (GCS score ≤8) after initial resuscitation
- Unexplained confusion that persists for >4 hours
- Deterioration in GCS score after admission (pay greater attention to motor response deterioration)
- Progressive focal neurological signs
- A seizure without full recovery
- Definite or suspected penetrating injury
- A cerebrospinal fluid leak
Ongoing worrying signs (e.g., persistent vomiting, severe headaches) even with a normal CT.

Consider transfer of these patients to the neurosciences unit for observation.

Moderate and severe TBI are not covered in this topic. See Assessment of brain traumatic injury, acute .

Consider – tranexamic acid

Back

Consider –

tranexamic acid

Additional treatment recommended for SOME patients in selected patient group

Tranexamic acid should be used as soon as possible in patients with major trauma and active or suspected active bleeding.[71] In the absence of major trauma and active or suspected active bleeding, consider tranexamic acid as soon as possible within 2 hours of the injury, in the pre-hospital or hospital setting and before imaging, in patients with a head injury and a GCS score of 12 or less.[42]

Bear in mind that this is standard practice in some countries, including the UK, but not a routine approach worldwide.

Evidence: Tranexamic acid

TIn the UK, the National Institute for Health and Care Excellence (NICE) does not make a recommendation for the use of tranexamic acid in people with mild traumatic brain injury, stating that more research is required to assess whether the benefits outweigh the risk of blood clots in this population. NICE does make a recommendation to consider tranexamic acid in patients with a head injury and a GCS score of 12 or less who are not thought to have active extracranial bleeding.

As part of the 2023 update of the NICE head injury guideline, two randomised controlled trials (RCTs) were identified assessing the use of tranexamic acid in adults with traumatic brain injury and no suspicion of extracranial bleeding.[42] NICE did not find any evidence for children or infants.

Adults

After reviewing the evidence from these two RCTs the NICE committee made a weak recommendation to consider giving these patients tranexamic acid as soon as possible within 2 hours of injury, but only if the GCS score is ≤12.[42]

The first RCT was the CRASH-3 trial, a large, pragmatic RCT of tranexamic acid versus placebo in adults (aged 16 years old and over) with traumatic brain injury and a GCS score of ≤12 or any intracranial bleed on CT scan and no extracranial bleeding (n=12,737, mean age 42 years, 175 centres in 29 countries).[72][74]
A regimen of initial tranexamic acid intravenous infusion given over 10 minutes followed by a second over 8 hours, was compared with a saline placebo.
According to the trial protocol, patients had to be treated within 8 hours of injury; however, this was changed to less than 3 hours from injury part way through the trial.

Overall 9202 (72%) of participants were enrolled within 3 hours.

28% of participants had a mild traumatic brain injury (33% moderate and 38% severe).
There was no significant difference in the primary outcome of head injury-related death at 28 days (18.5% tranexamic acid versus 19.8% placebo; relative risk [RR] 0.94, 95.0% CI 0.86 to 1.02, moderate quality evidence as assessed by GRADE).
There was also no significant difference when patients with severe injury (GCS 3 or bilateral unreactive pupils) were excluded from the analysis, or in all-cause mortality for the whole population.
There were, however, fewer head injury-related deaths within the first 24 hours (RR 0.81, 95% CI 0.69 to 0.95).
There were also fewer head injury-related death at 28 days in the subgroup of patients with less severe injuries (GCS 9-15: 5.8% tranexamic acid vs. 7.5% placebo; RR 0.78, 95.0% CI 0.62 to 0.95; patients with bilateral reactive pupils: 11.5% tranexamic acid vs. 13.2% placebo; RR 0.87, 95% CI 0.77 to 0.98).
There was no evidence of increased complications or adverse events including vascular occlusive events, seizures, sepsis, or renal failure with tranexamic acid.
CRASH-3 did not report outcomes separately for patients with mild and moderate traumatic brain injury. Correspondence from the study authors, requested by the NICE committee, suggested significant uncertainty about the effectiveness of tranexamic acid in people with mild traumatic brain injury, although no additional data was shared.[42]

The second RCT (n=1280, 20 centres and 39 emergency medical services agencies in the US and Canada) compared a single bolus of tranexamic acid with placebo within 2 hours of traumatic brain injury given in a prehospital setting.[73]

4% of participants had a mild traumatic brain injury (39% moderate and 57% severe). Subgroup results for outcomes by severity of injury were not reported.
The evidence suggested a reduced all-cause mortality with tranexamic acid compared to placebo at 28 days (absolute effect 49 fewer per 1000, 95% CI 89 fewer to 9 more) and at 6 months (absolute effect 40 fewer per 1000, 95% CI 87 fewer to 30 more).
There was no clinically important difference in hospital-free days at 28 days, neurosurgical intervention at 28 days, degree of disability at discharge and 6 months (measured by Glasgow Outcome Scale-Extended >4) or serious adverse events (myocardial infarction, pulmonary embolism, deep vein thrombosis, or thrombotic stroke).

The NICE 2023 guideline did not make a separate recommendation for older adults as they were awaiting results from the CRASH-4 trial looking specifically at this population.[42][75]

Children and infants

Due to the lack of evidence in children and infants, the NICE guideline committee extrapolated from the evidence in adults to people aged <16 years in the same recommendation, just with separate advice regarding dosage.[42]

Primary options

tranexamic acid: children ≥1 month of age: 15-30 mg/kg intravenously as a single dose given as soon as possible within 2 hours of the injury, maximum 2 g/dose; adolescents ≥16 years of age and adults: 2 g intravenously as a single dose given as soon as possible within 2 hours of the injury

Consider – antiemetic

admission not indicated

1st line – supportive care

Consider – antiemetic

Consider – observation (in children)

Back

Consider –

observation (in children)

Additional treatment recommended for SOME patients in selected patient group

Children who do not meet the criteria for an urgent computed tomographic (CT) scan (see the Diagnosis section) should be observed in the accident and emergency department or observation ward for a minimum of 4 hours prior to consideration for discharge if they have only 1 of the following risk factors:[42]

Loss of consciousness lasting >5 minutes (witnessed)
Abnormal drowsiness
≥3 discrete episodes of vomiting
Dangerous mechanism of injury (a high-speed road traffic accident either as a pedestrian, cyclist, or vehicle occupant; a fall from a height >3 metres; a high-speed injury from a projectile or other object)
Amnesia (antegrade or retrograde) lasting >5 minutes.

Note that having >1 of the above risk factors is a criterion for requesting an urgent CT scan (see the Diagnosis section).[42]

If any of the following risk factors occurs during observation, request an urgent (i.e, within 1 hour) CT head scan:[42]

Glasgow Coma Scale score <15
Further vomiting
A further episode of abnormal drowsiness.

If none of these risk factors occurs during observation, use your clinical judgement to determine whether a longer period of observation is needed.[42]

Consider – discharge plus home observation

Back

Consider –

discharge plus home observation

Additional treatment recommended for SOME patients in selected patient group

People admitted after a head injury may be discharged after resolution of all significant symptoms and signs, provided they have suitable supervision arrangements at home, in custody or in continued care.[42] Consider discharging the patient from the accident and emergency department or observation ward and transfer to the community for subsequent care if:[52]

Computed tomographic (CT) scan is not indicated (based on history and examination) and the patient is considered at low risk of clinically important brain injury
CT scan is normal and the patient is considered at low risk of clinically important brain injury and Glasgow Coma Scale (GCS) score has returned to 15, clinical examination is normal, and no other factors that would warrant a hospital admission are present (e.g., drug or alcohol intoxication, other injuries, shock, suspected non-accidental injury, meningism, cerebrospinal fluid leak).

Discharge patients only if there is somebody suitable at home to supervise them.[42]

Practical tip

Do not discharge infants and young children until they have achieved a GCS score of 15 or have normal consciousness as assessed using the paediatric version of the GCS.[42] BPNA: Child’s Glasgow Coma Scale Opens in new window

Advise that a responsible adult stays with the patient for the first 24 hours after the injury. Advise the patient and/or family/carers to return to the accident and emergency department if they develop focal weakness, persistent or worsening headache or vomiting, decrease in consciousness, rhinorrhoea, otorrhoea, or agitation. Give self-care advice.

confirmed mild traumatic brain injury: in the community

1st line – consider transfer to hospital

Back

1st line –

consider transfer to hospital

Refer any adult or child with a head injury to the accident and emergency department if during your assessment you identify any of the following risk factors (which may indicate an intracranial complication or cervical spine injury):[42]

A Glasgow Coma Scale score <15 on initial assessment
Any loss of consciousness as a result of the injury
Any focal neurological deficit since the injury
Any suspicion of a skull fracture or penetrating head injury since the injury
Amnesia for events before or after the injury
Persistent headache since the injury
Any vomiting episodes since the injury (use clinical judgement regarding the cause of vomiting in those aged ≤12 years and the need for referral)
Any seizure since the injury
Any previous brain surgery
A high-energy head injury
Current bleeding or clotting disorders (liver failure, haemophilia)
Current anticoagulant therapy or antiplatelet therapy (excluding aspirin monotherapy)
Current drug or alcohol intoxication
Any safeguarding concerns (e.g., possible non-accidental injury or a vulnerable person is affected)
Continuing concern about the diagnosis.

Follow the treatment protocol above as for patients with Confirmed mild traumatic brain injury: in hospital.

In the absence of any risk factors above, consider referral to an emergency department if any of these factors are present, depending on judgement of severity:[42]

Irritability or altered behaviour, particularly in babies and children aged under 5 year
Visible trauma to the head not covered in the recommendations above but still of concern to the professional
No one is able to observe the injured person at home

If you suspect a cervical spine injury, ensure full cervical spine immobilisation before transfer of the patient to hospital.[42] See Acute cervical spine trauma in adults.

Consider – home observation and supportive care

Consider – antiemetic

Use of this content is subject to our disclaimer

Mild traumatic brain injury

Treatment algorithm

suspected traumatic brain injury (any severity)

stabilisation and supportive care

Practical tip

confirmed mild traumatic brain injury: in hospital

admission indicated

observation and supportive care

Practical tip

tranexamic acid

Evidence: Tranexamic acid

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

antiemetic

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

admission not indicated

supportive care

antiemetic

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

observation (in children)

discharge plus home observation

Practical tip

confirmed mild traumatic brain injury: in the community

consider transfer to hospital

home observation and supportive care

antiemetic

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options