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Head injury is the commonest cause of death and disability in people aged 1–40 years in the UK

About

• Head injury can be defined as any trauma to the head, other than superficial facial injuries.
• RTA, falls, assaults. Varies between age groups and geography
• This term is often used interchangeably with both brain injury and traumatic brain injury
• Most are minor and need few interventions.
• Can be closed (no skull fracture) or Penetrating (skull penetrating
• Seen in approximately 7% of major trauma and 5% mortality.
• Early neuroprotective measures can significantly improve outcomes.

Epidemiology

• Head injury refers to trauma that leads to Injury of the scalp, skull or brain
• 10% of A&E attendances, 25% admitted (UK)
• 1% come to the neurosurgeons. Young males at greater risk
• 50% of all trauma deaths, 60% of RTA death

Patterns of Brain Bleeds

Mechanism of Injury

• Direct trauma to brain with axonal shearing and micro/macrohaemorrhage
• Bleeding or oedema and raised ICP as brain contained in bony box of skull
• Blood, fracture and bone or CSF build up or Oedema will cause rise in ICP
• Primary (impact) injury) Occurs at time of trauma (cortical contusions, lacerations, diffuse axonal injury)
• Secondary injury ( potentially avoidable): hypoxia, ischaemia (as a result ofraised ICP and shock), oedema,intracranial haematoma, seizures infection)
• Specific Worrying Events
  • High speed motor vehicle accident
  • Fall from = 3 m height
  • Fall in elderly patients or with alcohol involved
  • Altered GCS
• Factors involved in Falls/head injury
  • See Falls assessment for older pts
  • Falls from height
  • Road traffic : Seatbelt, speed, type of impact, damage to car
  • Assault and violence
• Risk Groups
  • Bimodal age: Young adults (15 to 29 years) and the elderly
  • Men are twice as likely to suffer head injuries compared to women.
  • Main causes are RTA, Falls, Assaults
• Concerns
  • Subdural : older patient
  • Extradural: younger patient. Tear of middle meningeal artery. Lucid then coma
  • Traumatic ICH and traumatic SAH
  • Traumatic brain injury

Clinical: Part of a full trauma assessment

• Mechanism of injury. Was there LOC for how long
• Reduced GCS should suggest raised ICP and urgent CT and need for intubation
• Pupil dilation suggests brainstem compression in comatose patient
• Look for other injuries - broken ribs, femur, NOF
• CSF leaks from nose or ears suggests skull fracture
• Blood in the ear canals or behind the ear drum suggests skull fracture
• Battle's sign (bruising over the mastoid processes) suggests skull fracture
• Panda eyes suggests significant injury
• If awake then full neuro assessment for vision, weakness, tingling
• Assess for headache, vomiting

Investigations

• Who gets a CT head (Within 1 hr of arrival)
  • GCS < 13 on initial assessment in the ED.
  • GCS < 15 at 2 hours after the injury on assessment in ED.
  • Suspected open or depressed skull fracture.
  • Sign of basal skull fracture (haemotympanum, 'panda' eyes, CSF leakage from the ear or nose, Battle's sign).
  • Post-traumatic seizure.
  • Focal neurological deficit.
  • More than 1 episode of vomiting.
• For adults with any of the following risk factors who have experienced some loss of consciousness or amnesia since the injury should get a CT head within 8 hrs
  • Age 65 years or older.
  • Any history of bleeding or clotting disorders and on anticoagulation
  • 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 metre or 5 stairs).
  • More than 30 minutes' retrograde amnesia of events immediately before the head injury.

Complications of a Head injury

Management

• ABCDE as ever. IV access. Oxygenate target 94-98%. Protect neck until no injury proven. Airway patency should be assessed and the cervical spine immobilised.
• If GCS < 9 then immediately call an anaesthetist and get airway protected. The airway should be secured, by tracheal intubation, in patients who do not have a patent airway or who are significantly obtunded (GCS = 8). Avoid NG tube if base of skull fracture suspected or proven
• The anaesthetist can expertly manage the ABC whilst you can sort out the neurology and other issues. In major trauma the chest should be examined and any life-threatening injuries (e.g. tension pneumothorax, open pneumothorax, massive haemothorax, flail chest, cardiac tamponade) promptly treated
• Get urgent CT head and neck to determine the extent of injury and need for ITU and/or neurosurgical input.
• Reverse any anticoagulation if any signs of SAH/SDH/EDH/ICH or at risk of bleeding or risks exceed benefits. Keep Platelets well above 50. Target around 100.
• Observations: GCS (every 30 minutes until GCS equal to 15 has been achieved) also
  • Pupil size and reactivity
  • Limb movements
  • Respiratory rate
  • Heart rate
  • Blood pressure
  • Temperature
  • SpO₂
• The minimum frequency of observations for patients with GCS equal to 15 should be as followed, starting after the initial assessment in the emergency department:
  • Half-hourly for 2 hours
  • 1 hourly for 4 hours
  • 2 hourly thereafter
• Should the patient with GCS = 15 deteriorate at any time after the initial 2 hour period, observations should revert to half-hourly and follow the original frequency schedule.
• There must be prompt urgent reappraisal by the supervising doctor if any of the following examples of neurological deterioration occur:
  • Development of agitation or abnormal behaviour
  • A sustained (for at least 30 minutes) drop of 1 point in GCS score (greater weight should be given to a drop of 1 point in the motor response score of the GCS).
  • Any drop of 3 or more points in the eye-opening or verbal response scores of the GCS, or 2 or more 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.
• Intubate and ventilate the patient immediately in the following circumstances
  • GCS =8
  • Loss of protective laryngeal reflexes
  • Ventilatory insufficiency as judged by blood gases: hypoxaemia (PaO₂ <13 kPa on oxygen) or hypercapnia (PaCO₂ >6kPa)
  • Spontaneous hyperventilation causing PaCO₂ <4kPa
  • Irregular respirations
• If transferring from a trauma unit to major trauma centre, intubation and ventilation prior to the start of the journey is indicated in the following circumstances:
  • Significantly deteriorating conscious level (1 or more points on the motor score), even if GCS not =8.
  • Unstable fractures of the facial skeleton
  • Copious bleeding into the mouth (for example, from skull base fracture)
  • Seizures
• Ventilate an intubated patient with muscle relaxation and appropriate short acting sedation and analgesia. Aim for:
  • PaO₂ >13 kPa
  • PaCO₂ 4.5 – 5.0, unless there is clinical or radiological evidence of raised intracranial pressure, in which case more aggressive hyperventilation is justified. If hyperventilation is used, increase the oxygen concentration.
  • Maintain the mean arterial pressure at =80mmHg by infusion of fluid and vasopressors as indicated
• Pain can lead to an increase in intracranial pressure and should be managed effectively. Treat significant pain with small doses of intravenous opioids titrated against clinical response and baseline cardiorespiratory measurements. All patients with head injury should receive paracetamol (IV or PO) if not contraindicated.
• Neurosurgical involvement is indicated if any of the following are present with a Surgically significant abnormality on imaging and
  • Persisting coma (GCS =8) after initial resuscitation
  • Unexplained confusion which persists for more than 4 hours
  • Deterioration in GCS score after admission (greater attention should be paid to motor response deterioration)
  • Progressive focal neurological signs
  • A seizure without full recovery
  • Definite or suspected penetrating head injury
  • A cerebrospinal fluid leak
  • Neurosurgical shunt for CSF diversion
  • Discuss with a neurosurgeon the care of all patients with new, significant abnormality on imaging
• For a rapid overview of head injury management, please see the separate key points document “Care of Head Injured Patients"
• Levetiracetam (Keppra) is first line anticonvulsant for patients with significant head injury. Start levetiracetam 1g twice daily with no loading dose needed. Give IV at first. Give subsequent doses via NG/PO if absorbing feed, otherwise continue IV Continue treatment for 7 days THEN STOP. May need longer duration and/or increased doses if clinical or EEG evidence of seizures during treatment. Maximum doses 1.5g twice daily
• Patients already taking anticonvulsants who sustain a head injury should have their anticonvulsant therapy discussed with a neurosurgeon.
• Rehabilitation: Can be challenging with significant behavioural issues with TBI often affecting young men and needs professionals with specialist skills. Will need specialist OT/PT and psychology and living support. Access to specialist neurorehabilitation for those with potential is vital.

References

• Guidelines for the Management of Traumatic Brain Injury
• Management of Severe Traumatic Brain Injury