Brain Haemorrhages and Fractures Flashcards
what does TBI stand for
traumatic brain injury
what is a common cause of brain haemorrhage
Trauma - Head Injury - RTA = one of the most severe causes, assault, accident trips and falls, sports-related injuries, industrial accidents
facts and figures involving head injuries
each year, around 700,000 people attend A&E with a head injury
more than 80% only have a minor injury
around 3/4 of those with head injuries are male
nearly half the people with head injuries are children
how has risk of head injuries been reduced
legislative measures - seatbelt in cars, anti-drink drive campaigns, bicycle/sports helmets
reducing hazards in the home that may cause a fall
childproofing the home
using correct safety equipment for work and DIY
what is a ‘head injury’ defined by the NICE guidelines
‘any trauma or the head or superficial injuries to the face’ caused when an external mechanical force causes an insult to the brain
what 2 categories can brain injuries fall into - explain
primary - occurring at time of injury - cannot be altered/reversed
secondary - occurring later - often amenable to prevention/reversal
how to decrease a secondary brain injury
early diagnosis and rapid appropriate treatment
causes of secondary brain injury - 5 points
hypoxia hypovolaemia intracranial haematoma causing pressure effects cerebral oedema infection
signs and symptoms of head injury - 13 points
Headache Reduced or loss of consciousness Acute neurological deficit (motor/sensory) Reduced GCS Confusion Agitation Decreased alertness Nausea/Vomiting Seizures Diplopia Seizures Rhinorrhoea Otorrhoea
describe the Glasgow coma scale
a practical method for assessment of impairment of conscious level in response to defined stimuli
1974
easily repeatable measure of conscious state and neurological ability
what is the primary investigation of choice for head injury and what do the guidelines advise
CT
advises who gets a CT scan and the time scale
which modality is not the imaging modality of choice and why
MRI
accessibility - not for the patient in the acute scenario, contraindicated due to its magnetic field
inability to screen the unconscious patient - requires a number of staff who are unaware of the magnetic field hazard
staff would have to go through safety screening - time consuming
CT provides similar information for most clinical purposes
what is the criteria for an ‘immediate’ scan and a ‘delayed’ scan
immediate = < 1hr delayed = within 8 hrs
when else should a CT scan be carried out within 8 hours
patients on warfarin presenting with a head injury in the absence of other indications
or immediately if 8 hrs has already elapsed
what are the 6 types of haemorrhage
extradural haemorrhage - trauma
subdural haemorrhage - trauma
contusion - trauma
diffuse axonal injury- trauma, complex (MRI)
subarachnoid haemorrhage - trauma, spontaneous
intracerebral haemorrhage - trauma, spontaneous
describe extradural haemorrhage
occurs between dura mater and skull
requires trauma to draw dura from bone, skull in 80% of cases
stripping of dura from bone = laceration of the arteries - usually the middle meningeal artery
arterial bleed = confined by limits of dura where its torn away or by the sutures
radiographic appearance of extradural haemorrhage
typically bi-convex/lentiform hyperdensity
who is mainly affected?
how can it present
typically affects young patients involved in a clearly defined blow (assault/fall/sports-injury etc)
newborns - due to abnormal/difficult labour or forceps delivery
severe headache - due to ripping of the dura from skull
?LOC - depends on force of impact
classic lucid interval after concussive force of blow
patient regains consciousness but the EDH continues to expand = mass effect = increased intracranial pressure = decreased level of consciousness and possible coning
describe subdural haemorrhage
severe or minor head injury causes rapid acceleration/deceleration of the brain tissue
bridging veins tear = low pressure venous bleeding
large haematomas can form before clinical signs appear
associated with cerebral atrophy - common in elderly and alcoholics
bridging veins under greater tension as the brain gradually shrinks from skull
easily ruptured - with only minor trauma
radiographic appearance of subdural haemorrhage
between dura mater and arachnoid mater
crescent, concave, sickle shape
time of presentation since injury is important because radiographic density of blood alters with age
ACUTE - hyper dense
SUBACUTE - isotense (4-21 days after)
CHRONIC - hypodense (21 days or more after)
who does it affect?
> 60yrs, more common in men than women
puts with clotting disorders including alcoholics
associated with NAI - shaken baby syndrome
how is acute usually presented and chronic usually presented
ACUTE
usually younger patients/alcoholics due to the way they present
rates of mortality and morbidity = high
emergency management = critical
CHRONIC
usually seen in elderly
often slow deterioration seen in patient as haematoma expands
gradual onset of confusion, decreased level of consciousness, headache, difficulty with gait or balance, memory loss
describe contusion
bruise on the brain
often occurs in frontal and temporal regions due to brain colliding with the brain protuberances within the skull
blood vessels are damaged and haemorrhage due to direct trauma
radiographic appearance of contusion
often multiple small haemorrhages at grey/white matter interface
delayed scan demonstrates oedema and atrophy
