Head Injury Flashcards
Epidemiology
- Hospital Episode Statistics data for the 2012-2013 annual dataset indicate that there were 171,600 admissions to hospitals in England with a primary diagnosis of head injury.[3]
- 70% are males.
- 33-50% are children under 15 years of age.[2]
- There is an increasing number of patients admitted with head injuries aged ≥75 years (approaching 40%).[3]
- Severe traumatic brain injury defined as Glasgow Coma Score (GCS) <9, has a bimodal presentation - 15-25 years and 65-75 years. This occurs in 11,000 people per year and has a mortality rate reaching 50%
Assessment
In patients with normal or near-normal GCS and who are alert
- Haemodynamic status - pulse rate, blood pressure, fluid status.
- Neurological assessment - full history and examination, make notes of pupil size and reaction to light.
- Look for other possible injuries and any other relevant examination
Assessment
In patients with reduced GCS
Resuscitate but make a quick assessment of GCS and pupils. The priority is to get the patient to hospital and CT scanned within the first hour after injury
Prehospital management
Resuscitation
- Airway - endotracheal intubation should only be performed by those experienced and with concomitant anaesthesia (risk of increasing intracranial pressure). Insertion of laryngeal mask airways is easy and provides a good seal around the oropharynx.[4]
- Breathing - oxygen should be provided with an aim to beginning ventilation as soon as possible. End tidal CO2 monitoring is advisable, as hyperventilation is associated with poorer outcomes, probably relating to cerebral vasoconstriction.
- Circulation - the systolic blood pressure should be maintained >90 mm Hg ensuring an adequate cerebral perfusion pressure - eg, boluses of 0.9% normal saline
Full cervical spine immobilisation
Attempted (unless other factors prevent this) if:
GCS is <15 at any time since the injury.
There is neck pain or tenderness.
There is focal neurological deficit.
There is paraesthesia in the extremities.
Any other clinical suspicion of cervical spine injury exists.
An alerting call to the destination A&E department should be made for all patients with a GCS <15
Indications for referral to hospital A&E department
History of head injury:
- A high-energy head injury - eg, diving accident, high-speed motor vehicle collision.
- GCS <15 at any time since injury.
- Any loss of consciousness as a result of the injury.
- Any focal neurological deficit since the injury.
- Amnesia for events before or after the injury.
- Persistent headache since the injury.
- Any vomiting episodes since the injury (clinical judgement should be used in those aged ≤12 years).
- Any seizure since the injury.
- Irritability or altered behaviour, particularly in infants and young children.
- Any suspicion of a skull fracture or penetrating head injury since the injury (eg, clear fluid from the ears or nose, black eye with no associated damage around the eyes, bleeding from one or both ears, new deafness in one or both ears, bruising behind one or both ears).
- Visible trauma to the head not covered above but still of concern to the professional.
Past history
Age ≥65 years.
Any previous cranial neurosurgical interventions.
History of bleeding or clotting disorder.
Current anticoagulant therapy such as warfarin or newer oral anticoagulants.
Other concerns
Suspicion of non-accidental injury.
Current drug or alcohol intoxication.
Adverse social factors (eg, no one able to supervise the injured person at home).
Continuing concern by the professional about the diagnosis.
Continuing concern by the injured person or their carer about the diagnosis.
Admission
Adult
New, clinically significant abnormalities on imaging.
Not returned to GCS equal to 15 after imaging, regardless of the imaging results.
When a patient fulfils the criteria for CT scanning but this cannot be done.
Continuing worrying signs (eg, persistent vomiting, severe headaches).
Other sources of concern - eg, drug or alcohol intoxication, other injuries, shock, suspected non-accidental injury, meningism, CSF leak).
Children
History of loss of consciousness.
Neurological abnormality, persisting headache or vomiting.
Clinical or radiological evidence of skull fracture or penetrating injury.
Difficulty in making a full assessment.
Suspicion of non-accidental injury.
Other significant medical problems.
Not accompanied by a responsible adult or social circumstances considered unsatisfactory.
Patients not requiring admission
All patients and their carers should be given clear advice, both in verbal and written form. This should include information on:[2, 6]
Details of the injury - including the nature and severity.
Warning signs that warrant further immediate medical assessment:
Increasing drowsiness.
Worsening headache.
Confusion or strange behaviour.
Two or more bouts of vomiting.
Focal neurological problem - eg, limb weakness.
Dizziness, loss of balance, or convulsions.
Any visual problems such as blurring of vision, or double vision.
Blood, or clear fluid, leaking from the nose or ear.
Unusual breathing patterns.
That a responsible adult will stay with the patient until the first 24 hours following the injury.
How long recovery is likely to take and what this will involve - including when they can go back to work and undertake everyday activities (eg, school and sports).
Potential complications.
Whom to contact if further help is needed.
Available support organisations.
Investigations
Selection of adults for CT scan:
Selection of adults for CT scan:
CT scan of the brain within one hour (with a written radiology report within one hour of the scan being undertaken):
- Glasgow Coma Scale (GCS) <13 when first assessed or GCS <15 two hours after injury
- Suspected open or depressed skull fracture
- Signs of base of skull fracture*
- Post-traumatic seizure
- Focal neurological deficit
- >1 episode of vomiting
All patients with a coagulopathy or on oral anticoagulants should have a CT brain scan within eight hours of the injury, provided there are no other identified risk factors, as listed above. Again, a written radiology report should be available within one hour of the scan being undertaken.
Investigations
Selection of children for CT scan:
CT scan of the brain within one hour (with a written radiology report within one hour of the scan being undertaken):
- Clinical suspicion of non-accidental injury
- Post-traumatic seizure (no past medical history of epilepsy)
- GCS <14 on initial assessment or, if <1 year, GCS <15 GCS <15 two hours after injury
- Suspected open or depressed skull fracture or tense fontanelle
- Signs of base of skull fracture*
- Focal neurological deficit
- Aged <1 - bruise, swelling or laceration >5 cm on the head
If none of the above are present then CT brain scan within one hour if more than one of the following are present (with a written radiology report within one hour of the scan being undertaken):
- Witnessed loss of consciousness >5 minutes
- Amnesia (antegrade or retrograde) >5 minutes
- Abnormal drowsiness
- ≥3 Discrete episodes of vomiting
- Dangerous mechanism of injury (high-speed RTA, fall from >3 m, high-speed projectile)
If only one of the aforementioned risk factors is present then observe for a minimum of four hours - CT scan of the brain within one hour if any of the following occur (with a written radiology report within one hour of the scan being undertaken):
- GCS <15
- Further vomiting
- Abnormal drowsiness
Investigations for the cervical spine
Always consider the possibility of cervical spine injury in cases of head injury.
CT of the cervical spine should be undertaken within one hour if there is a head injury and any one of the following:
GCS is <13.
The patient is intubated.
Plain X rays are abnormal or technically inadequate.
A definitive diagnosis is needed - eg, before surgery.
The patient is alert and stable and there is a clinical suspicion of cervical injury with any one of the following:
- Age 65 years or older.
- Dangerous mechanism of injury - eg, a fall of height >1 m, a fall down five stairs, axial load to head.
- Focal neurological deficit.
- Paraesthesia in the upper or lower limbs.
Other areas are also to be scanned - eg, multi-region trauma.
Indications for neurosurgical opinion
- New, surgically significant abnormalities on imaging.
- Persisting coma (GCS ≤8) after initial resuscitation.
- Unexplained confusion which persists for more than four 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.
- Depressed skull fracture.
- Definite or suspected penetrating injury.
- A CSF leak.
Management
The following statements relate to the routine management of patients following a head injury:
- early nutritional support may be associated with a trend towards better outcomes in terms of survival and disability.E
- One large study showed an increase in mortality with steroids suggesting that steroids should no longer be used routinely in people with traumatic head injury.There is no reduction in mortality with methylprednisolone in the two weeks after head injury.
- There is no consistent evidence that hypothermia is beneficial in the treatment of head injury.
- High-dose mannitol is beneficial in the pre-operative management of patients with acute intracranial haematomas. There are insufficient data on the effectiveness of pre-hospital administration of mannitol for acute traumatic brain injury.[
- Prophylactic anti-epileptics are effective in reducing early seizures, but there is no evidence that treatment with prophylactic anti-epileptics reduces the occurrence of late seizures
Mannitol
Mannitol is an osmotic diuretic that is metabolically inert in humans and occurs naturally, as a sugar or sugar alcohol, in fruits and vegetables. Mannitol elevates blood plasma osmolality, resulting in enhanced flow of water from tissues, including the brain and cerebrospinal fluid, into interstitial fluid and plasma.
Complications
- Amnesia: common, and may be retrograde and/or antegrade.
- Raised intracranial pressure, cerebral oedema.
- Cerebral herniation.
- CSF leak (test fluid for glucose or drop on filter paper to see double halo):
- From the ear - possible fracture of petrous temporal bone, may involve VII/VIIIth nerves, leak closes spontaneously, lower risk of meningitis.
- From the nose - possible fracture of cribriform plate, may originate from ear, anosmia, leak may require surgery, don’t blow nose or insert nasogastric tube.
- Meningitis: following skull fracture, may occur weeks to years later. The role of prophylactic antibiotics for CSF leak are controversial
Intracranial haemorrhage:
- Extradural: not common. Classically, the middle meningeal artery is torn under a temporal bone fracture and follows an injury-lucid interval coma pattern. However, many are non-classical. 80% progress to uncal herniation. Immediate evacuation of the haematoma is required.
- Subdural: caused by sudden acceleration-deceleration of brain parenchyma with tearing of the bridging veins. Common in severe traumatic brain injury, atrophic brains (the elderly, alcoholics) and children aged <2. May be acute (<24 hours), subacute (1-14 days) or chronic (>2 weeks). There may be few signs with chronic subdurals. High morbidity and mortality if acute. Surgery is usually required.
- Subarachnoid: the most common haemorrhage in moderate-to-severe injury. May present with meningeal signs and has a significant mortality. Nimodipine shows a beneficial effect in brain injury patients with subarachnoid haemorrhage, but the increase in adverse reactions indicates that the drug is harmful for some patients.[19]
- Intracerebral: cerebral contusions are common and often associated with a subarachnoid haemorrhage. Intracerebral haemorrhage can occur days after significant blunt trauma, often at the site of resolving contusions (especially in patients wit
