Head injury Flashcards
what is an extradural haematoma?
Bleeding into the space between the dura mater and the skull.
Often results from acceleration-deceleration trauma or a blow to the side of the head.
The majority of extradural haematomas occur in the temporal region where skull fractures cause a rupture of the middle meningeal artery.
features of extradural haematoma
Raised intracranial pressure
Some patients may exhibit a lucid interval
what is a subdural haematoma?
Bleeding into the outermost meningeal layer.
Most commonly occur around the frontal and parietal lobes.
May be either acute or chronic.
risk factors of subdural haematoma?
old age
alcoholism
onset of subdural haematoma in comparison to extradural haematoma
Slower onset of symptoms than a extradural haematoma.
what is a subarachnoid haemorrhage?
Usually occurs spontaneously in the context of a ruptured cerebral aneurysm, but may be seen in association with other injuries when a patient has sustained a traumatic brain injury.
when does a secondary brain injury occur?
cerebral oedema, ischaemia, infection, tonsillar or tentorial herniation exacerbates the original injury.
what is the cushings effect
(hypertension and bradycardia) often occurs late and is usually a pre terminal event
Mx of life threatening rising of ICP such as in an extradural haematoma
whilst theatre is prepared or transfer arranged use of IV mannitol/ frusemide
Mx of diffuse cerebral oedema
decompressive craniotomy
how are open depressed skull fractures managed
formal reduction and debridement
how are closed depressed skull fractures managed
non-operatively
when is ICP monitoring appropriate?
GCS 3-8
Normal CT scan
when is ICP monitoring mandatory
GCS 3-8
abnormal CT scan
what is the minimum cerebral perfusion pressure in adults?
70 mmHg
what is the minimum cerebral perfusion pressure in kids?
40-70 mmHg
3rd nerve compression secondary to tentorial herniation pupils and light response
unilaterally dilated
sluggish or fixed
poor CNS perfusion and bilateral 3rd nerve palsy pupils and light response
bilaterally dilated
sluggish or fixed
optic nerve injury pupils and light reflex
unilaterally dilated or equal
cross reactive (Marcus-Gunn)
OPiates, pontine lesions and metabolic encephalopathy pupils and light reflex
bilaterally constricted
maybe difficult to assess
sympathetic pathway disruption pupils and light reflex
unilaterally constricted
preserved
CT head with in 1 hour
GCS < 13 on initial assessment
GCS < 15 at 2 hours post-injury
suspected open or depressed skull fracture
any sign of basal skull fracture (haemotympanum, ‘panda’ eyes, cerebrospinal fluid leakage from the ear or nose, Battle’s sign).
post-traumatic seizure.
focal neurological deficit.
more than 1 episode of vomiting
CT head with in 8 hours
age 65 years or older
any history of bleeding or clotting disorders including anticogulants
dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of greater than 1 metre or 5 stairs)
more than 30 minutes’ retrograde amnesia of events immediately before the head injury
CT head with in 8 hours
age 65 years or older
any history of bleeding or clotting disorders including anticogulants
dangerous mechanism of injury (a pedestrian or cyclist struck by a motor vehicle, an occupant ejected from a motor vehicle or a fall from a height of greater than 1 metre or 5 stairs)
more than 30 minutes’ retrograde amnesia of events immediately before the head injury
