Flashcards in Traumatic Brain and Head Injury Deck (24):
what is a traumatic brain injury?
non-degenerative, non-congenital insult to the brain from an external mechanical force, possibly leading to temporary or permanent impairment of cognitive, physical and psychosocial functions
TBI is the commonest cause of death and disability in people age 1-40 in UK - true or false?
what groups are high risk to TBI?
young men and elderly
previous head injuries
residents of inner cities
alcohol and drug abuse
what are examples of mechanism of TBI?
what GCS score is mild?
14 or 15, brief LOC
what GCS score is moderate?
what GCS score is severe?
NICE states that patients who have sustained head injury with any of what risk factors should have CT within one hour?
GCS <13 initially
GCS <15 at 2 hours
suspected open or depressed skull fracture
any sign of basal skull fracture
post traumatic seizure
focal neurological deficit
more than one vomiting episode
suspicion of NAI
CT should also be immediately requested in patients with what risk factors if they experienced some LOC or amnesia since injury?
age 65 or more
dangerous mechanism of injury
what are the two different types of head injury?
focal (traumatic haematoma or contusion)
what are the three types of traumatic haematoma?
why would surgery take place in a traumatic head injury?
to control and monitor ICP/CPP (CPP = MAP - ICP)
prevent secondary insults
decompressive craniectomy = portion of skull is removed to give room for swelling brain
how is raised ICP treated?
sedation: propofol, benzodiazepines, barbiturates
maximise venous drainage of brain
osmotic diuretics: mannitol, hypertonic saline
how can you maximise venous drainage of brain?
head of bed tilt
cervical collars, ET tube ties
brainstem death must be diagnosed by who?
2 doctors, one of which is a consultant
what are the symptoms of brainstem death?
no pupil response
no corneal reflex
no gag reflex
no vestibulo-ocular reflex
no motor response
can you recover from brainstem death?
what are the symptoms of an extradural haematoma?
injury with LOC
rapid progression of neurological symptoms
what neurological symptoms do you get in extradural haematoma?
unilateral fixed and dilated pupil
apnoea and death
what is diffuse axonal injury (DAI)
brain injury which occurs in scattered lesions in white matter tracts and grey matter over a widespread area
what causes diffuse axonal injury?
excitotoxicity and apoptosis
inflammatory mediator release
how are sheering forces classified and where do they occur?
adams classification (1-4)
occur where density difference is greatest = grey / white interface
how does excitotoxicity and apoptosis occur?
excitatory amino acids e.g. glutamate activated NMDA receptors resulting in Ca2+ mediated activation of proteases and lipases causing in further cell death