Traumatic Brain and Head Injury Flashcards
What is a head injury defined as?
Non-degenerative, non-congenital insult to the brain from an externa mechanical force
How common are traumatic head injuries?
Very = commonest cause of death and disability in people age 1-40
What are the high risk groups for traumatic head injuries?
Young men and elderly, previous head injuries, residents of inner cities, alcohol and drug abuse, low income
What are the common mechanisms of injury for traumatic head injuries?
Assault, falls, RTCs, sports, over half involve alcohol
What occurs in the initial management of a traumatic head injury?
ATLS management = GCS, pupils, ABCs
Secondary survey = other injuries (C spine)
History = what happened and when, age, pre-existing PMH, drugs
What are the categories of the Glasgow Coma Scale?
Eye opening = open spontaneously, to speech/pain, no eye opening
Motor = obeying, localising, abnormal flexing, extending, no motor response
verbal = orientated, confused, inappropriate, incomprehensible, no verbal
What is the grading of the head injury severity scale?
Mild = 14 or 15, brief loss of consciousness Moderate = 9-13 Severe = 3-8
What patients should receive a CT within an hour of admission?
GCS <13 on initial assessment or <15 at 2hrs post injury
Suspected open or depressed skull fracture
Any sign of basal skull fracture
Post traumatic seizure or focal neurological deficit
More than one episode of vomiting
Suspicion of NAI
What patients should receive an immediate CT is they are experiencing loss of consciousness or amnesia?
Age >=65, coagulopathy, dangerous mechanism of injury
What are the categories of head injury?
Focal = traumatic haematoma, contusion Diffuse = DAI
What are the types of haematoma?
Extradural, subdural or intracerebral
What is the classic presentation of a traumatic head injury?
Injury with loss of consciousness and recovery lucid period = rapid progression of neurological symptoms
What are some of the symptoms of traumatic head injuries?
Deteriorating GCS, possible hemiparesis, unilateral fixed and dilated pupil, apnoea and death
What is the neurosurgical role in traumatic head injuries?
To prevent secondary insults = hypoxia, hypotension, mass lesions, controlling ICP and CPP
What factors are considered in the surgical decision process?
Age, GCS, haemodynamically stable, PMH and drug history, blood results, CT results, guidelines
What is the management of raised ICP?
Sedation = propofol, benzodiazepines, barbiturates
maximise venous drainage of brain = head pf bed tilt, cervical collars, CO2 control
Osmotic diuretics = mannitol, hypertonic saline
CSF release = decompressive craniectomy
What are some features of seizures?
Can cause secondary insults
Anti-epileptic medication reduces early seizures, but not late seizures
How is diffuse axonal injury classified?
Adams classification (1-4) for DAI sheering interface
Where do diffuse axonal injuries occur?
Where density difference is greatest = grey/white interface
What occurs after a diffuse axonal injury?
Excitotoxicity and apoptosis with inflammatory mediator release
What occurs in excitotoxicity?
Excitatory amino acids (glutamate) activates NMDA receptors = calcium mediated activation of proteases and lipases, further secondary cell death
What inflammatory mediators are released following a diffuse axonal injury?
Cytokine and interleukins
High IL-6 levels associated with greater likelihood of death
Can brainstem death be treated?
No = recovery is impossible
What are the features of brainstem death?
No pupil response, corneal reflex, motor response, vestibulo-ocular reflex, gag reflex, cough reflex or respiration
What is needed to confirm brainstem death?
Confirmation by two doctors = one must be consultant
What are some issues that may occur after leaving hospital following a traumatic head injury?
Seizures, depression and mood swings Alcohol and drug dependence and suicide Personality change and aggression Recurrent behaviour = further head injuries Failure of relationships and loss of job
