head injury Flashcards
what are the local complications of skull fracture
meningeal artery tear (extradural haematoma), dural venous tear (subdural haematoma), CSF rhinorrhoea and otorrhoea
what are the mechanisms of traumatic brain injury
diffuse axonal injury, neuronal and axonal damage from direct trauma, brain oedema and incr ICP, brain hypoxia, brain ischaemia
what is diffuse axonal injury
shearing and rotational stresses on decelerating brain, sometimes at the site opposite the impact (contrecoup)
what can severe TBI be defined as
post traumatic amnesia >24hours, GCS 5/15
late sequelae of TBI
incomplete recovery- cognitive, hemiparesis; post traumatic epilepsy; post traumatic syndrome (dizzy, headache, malaise); BPPV; chronic subdural haematoma; hydrocephalus; chronic traumatic encephalopathy
what is chronic traumatic encephalopathy
cognitive, extrapyramidal and pyramidal signs. ‘punch drunk’
what happens in post traumatic epilepsy
depressed skull fracture, penetrating injury and intracranial haemorrhage increase risk. can happen up to a year after event. risk is not increased after mild injury
long term problems in survivors
cognitive- amnesia, neglect, disordered attention, motivation. behavioural/emotional- temper dyscontrol, depression, grief reactions
what is subdural haematoma
collection blood in subdural space following rupture of a vein. interval between injury and symptoms can be days- months
when is spontaneous SDH common
in the elderly and occurs with anticoagulants
symptoms/signs SDH
headache, drowsy, confusion, symptoms can fluctuate, focal deficits develop late (hemiparesis). increase ICP and seizures
what does CT/MRI show in SDH
clot and midline shift. crescent shaped collection of blood over one hemisphere, sickle shape
treat SDH
irrigation/evacuation via craniostomy. craniotomy is 2nd line. can resolve spontaneously
differential SDH
stroke, dementia, CNS masses
when does extra dural haemorrhage occur
typically after linear fracture, damage to middle meningeal artery (parietal or temporal bone). blood accumulates over mins-hours.
what happens in EDH
brief LOC then LUCID INTERVAL. after this patient is stuporose, ipsilateral dilated pupil, contralat hemiparesis, coning.
what happens later on to signs in EDH
bilat fixed dilated pupils, tetraplegia, resp arrest
symptoms EDH
decr GCS by incr ICP. severe headache, vomiting, confusion, fits, +- hemiparesis with brisk reflexes upgoing plantars
which type of brain bleed has a LUCID INTERVAL
extra dural haemorrhage
what does the CT show in EDH
biconvex/lens shaped, rounded
is LP contraindicated in EDH
YES
management EDH
clot evacuation +- ligation bleeding bvessel. may require intubation and ventilation
