[24] Head Injury Flashcards
What is a head injury?
Any trauma to the skull or brain
How can head injuries be broadly classified?
- Primary
- Secondary
What is a primary head injury?
Damage that occurs at time of impact
What are the types of primary head injuries?
- Focal
- Diffuse
What are the type of focal head injuries?
- Haematoma
- Contusion
What is a haematoma head injury?
Collection of blood within skull
What are the types of haematoma head injuries?
- Extradural
- Subdural
- Intracerebral
What is a contusion?
Bruising of the brain, whereby blood mixes with cortical tissue due to micro haemorrhages and small vessel leaks
What is a coup contusion?
A contusion at the site of impact
What is a contra-coup contusion?
Contusion at a site opposite point of impact
What are the types of diffuse head injury?
- Concussion
- Diffuse axonal injury
What is a concussion?
A head injury with temporary loss of brain function
What happens in a concussion?
Trauma leads to stretching of the axons
What does stretching of the axons in concussion lead to?
- Impaired neurotransmission
- Loss of ion regulation
- Reduction in cerebral blood flow
What is a diffuse axonal injury?
Shearing of the interface between the grey and white matter following traumatic acceleration/deceleration or rotational brain injuries, damaging the intra-cerebral axons and dendritic connections
What can axonal death in diffuse axonal injury lead to?
- Cerebral oedema
- Raised ICP
- Coma
What is a secondary brain injury?
Secondary brain injury occurs from insults to the brain after the initial injury (usually due to complications from the initial injury)
What can cause secondary brain injury?
- Cerebral oedema
- Haematoma
- Increased ICP
What is a skull fracture?
A fracture of one or more of the bones of the cranial vault or skull base
How are skull fractures classified?
- Appearance (linear or comminuted)
- Location
- Degree of depression
- Open or closed
What are open fractures of the skull?
Fractures that communicate with the skin through a wound, sinus, the ear, or the oropharynx
What are the non-traumatic causes of (often secondary) head injuries?
- Anoxia
- Infection
- CVA/TIA
- Tumour
- Metabolic disorder
What are the traumatic causes of open head injury?
- Assault
- Fall
- Surgery
What are the causes of closed traumatic head injury?
- Assault
- Fall
- Accident
- Abuse
What is the main risk factor for head injury?
Male
How do mild head injuries present?
- Headache
- Confusion
- Ringing ears
- Fatigue
- Changes in sleep pattern, mood or behaviour
How do moderate/severe head injuries present?
- Confusion or aggression
- Slurred speech
- Coma or impaired consciousness
- Persistent headache
- Nausea or vomiting
- Convulsions or seizures
- Abnormal dilation of eyes
What are some characteristic signs of basal skull fractures?
- CSF otorrhoea or rhinorrhoea
- Periorbital ecchymosis (raccoon eyes)
- Battle’s sign (bruising over mastoid)
- Haemotympanum
What is the mainstay investigation of suspected brain injuries?
CT head
When should adults receive a CT head within 1 hour of head injury?
- Have GCS <13 when first assessed or <15 2 hours after injury
- Suspected open or depressed skull fracture
- Signs of basal skull fracture
- Post-traumatic seizure
- Focal neurological defecit
- > 1 episode of vomiting
When should children receive a CT head within 1 hour of head injury?
- Clinical suspicion of NAI
- Post-traumatic seizure
- GCS <14 on initial assessment
- GCS <15 on initial assessment if <1 year old OR 2 hours after injury
- Suspected open or depressed skull fracture or tense fontanelle
- Signs of basal skull fracture
- Focal neurological deficit
- Aged <1 with head bruise, swelling or >5cm laceration
- More than one additional features
What additional features should be looked at in children with suspected brain injury when considering CT head
- Witnessed LoC >5 mins
- Amnesia > 5 mins
- Abnormal drowsiness
- 3 or more discrete episodes of vomiting
- Dangerous mechanism of injury
What patients should receive CT head within 8 hours of head injury, regardless of other features?
- Those with coagulopathy
- On oral anticoagulants
What are the differentials for traumatic brain injury?
- Intracranial haemorrhage (SAH)
- Suture lines in children
- Cephalohaematoma
Where should patients with a head injury be taken?
Centre which can provide resuscitation and manage head injuries
What initial treatment should patients with normal or near-normal GCS receive for head injury?
- Check of haemodynamic status
- Neurological assessment
- Look for other possible injuries
How should haemodynamic status be checked in patients with head injury and near normal GCS?
- Pulse rate
- Blood pressure
- Fluid status
What should a neurological assessment of a patient with a head injury and near-normal GCS include?
- Full history and examination
- Pupil size and reaction to light
What initial treatment should patients with a reduced GCS receive for head injury?
- Resucitation
- Further assessment of GCS and pupils
What are the indications for cervical spine immobilisation following head injury?
- GCS <15 at any time
- Neck pain or tenderness
- Focal neurological deficit
- Paraesthesia in extremities
- Any other clinical suspicion of cervical spine injury
Give some examples of criteria for admission to A&E with head injury?
- High energy injury e.g. RTA
- GCS <15 at any time
- Any LoC
- Any focal neurological deficit, vomiting, seizure, irritability or altered behaviour
- Any suspicion of skull fracture or penetrating head injury
- Any 65 or over
- History of bleeding or clotting disorder or current anti-coagulant therapy
- Suspicion of non-accidental injury
Give some examples of criteria for longer admission to hospital in adults with head injury?
- Abnormalities on imaging
- GCS still below 15 after imaging
- Continuing signs e.g. vomiting or headaches
- Other injuries
- Shock
- Suspected non-accidental injury (NAI)
Give some examples of criteria for longer admission to hospital in children with head injury?
- History of LoC
- Neurological abnormality
- Persistent headache or vomiting
- Evidence of skull fracture or penetrating injury
- Suspicion of NAI
- Difficulty in making full assessment
- Other significant medical problems
How can management of traumatic brain injury be divided?
- Acute phase
- Chronic phase
What is the aim of the acute phase management of traumatic brain injury?
- Stabilise patient
- Focus on preventing further injury
Why is the focus of acute phase management of traumatic brain injury not to reverse initial damage?
Not usually possible
What can be involved in the acute management of a traumatic brain injury?
- Ensure proper oxygen supply
- Maintain adequate blood flow to the brain
- Control raised ICP
- Prevent and treat any seizures
- Manage pain
What may be required in serious head injury to ensure proper oxygen supply?
Endotracheal intubation and mechanical ventilaiton
How can hypotension be managed in traumatic head injury?
- Fluids
- Adrenaline/similar drugs
How can raised ICP be managed following traumatic head injury?
- Tilt bed and straighten neck to promote venous return
- Sedate the patient
- Analgesia
- Mannitol can be used
How should seizures following traumatic head injury be managed?
Benzodiazepines
Why is important to manage pain following an acute head injury?
Pain can raise ICP
What are the indications for neurosurgical opinion following traumatic head injury?
- Surgically significant abnormalities on imaging
- Persisting GCS <8 (coma)
- Unexplained confusion beyond 4 hours
- Deterioration of GCS after admission
- Progressive focal neurological symptoms
- Seizure without skull fracture
- Definite or suspected penetrating injury
- CSF leak
What can neurosurgical intervention help to manage?
- Mass lesions e.g. haematomas
- Contusions
- Penetrating objects
What surgical intervention can help to manage raised ICP?
Decompressive craniectomy
What should patients be referred for following acute management of traumatic head injury?
Rehabilitation
What is the aim of rehabilitation following a traumatic head injury?
To improve independent functioning at home or in society and help adapt to disabilities
Which professionals are often involved in rehab post-traumatic brain injury?
- Neurologists
- Physios
- SALT
- OT
- Mental health professionals
How can rehabilitative care be delivered post-traumatic brain injury?
- Inpatient treatment unit
- Outpatient
- Community based
What further care may patients who cannot live alone or with family require post-traumatic brain injury?
Care in living facilities
What are the potential complications of traumatic head injury?
- Amnesia
- Raised ICP and cerebral oedema
- CSF leak
- Cerebral herniation
- Intracranial or extracranial haemorrhage
- Meningitis
- Seizures
- Permanent disability
Where can CSF leak following a traumatic head injury?
- Nose
- Ear
How can CSF leak from the nose following a traumatic head injury?
Fracture of cribriform plate
What should patients with CSF rhinorrhoea not do?
Blow their nose
How can CSF leak from the ear following a traumatic head injury?
Fracture of temporal bone
What may be involved if there is CSF otorrhoea?
- Facial nerve
- Vestibulocochlear nerve
What permanent disabilities may occur after a traumatic head injury?
- Neurodegenerative deficits
- Delusions
- Speech or movement problems
- Intellectual disability
- Coma or persistent vegetative state