Head Injury, Bleeds & Coma Flashcards
- Closed (concussional)
- or open (penetrating or blunt);
- acceleration, deceleration
- or rotational
What are these all types of?
Head injury!
Closed (concussional) or open (penetrating or blunt); acceleration, deceleration or rotational injury
What order incidence do these causes of head injuries with 1 being the top cause and 4 being the last –>.
Assault, falls, alcohol, RTA?
- Alcohol: 65%
- Assault: 30-50%,
- Falls: 22-45%
- RTA: 25% (more severe injuries),
What injury do these signs point to?
- haemotympanum,
- panda eyes (periorbital),
- CSF from ear/nose,
- Battle’s sign
SIGNS OF A BASAL SKULL FRACTURE
- Battle’s sign = bruising behind ears
- haemotympanum = blood in middle ear e.g. behind eardrum
What injuries type mostly occur to the scalp?
- simple penetrating injuries,
- debridement
- & suture
Damage to the anterior, middle and posterior fossa of the skull produce different symptoms.
Damage to which fossa produces these signs/symptoms?
- orbital haematoma,
- bleeding from the ear,
- CSF otorrhoea,
- CN 7,8 palsy including deafness
Middle fossa
- greater wing of sphenoid, temporal bone
Damage to the anterior, middle and posterior fossa of the skull produce different symptoms.
Damage to which fossa produces these signs/symptoms?
- nasal bleeding,
- orbital haematoma,
- CSF rhinorrhoea (rich in glucose, low mucin, +ve for tau protein),
- CN 1-6 palsy including anosmia,
- aerocele in paranasal sinuses
anterior fossa damage
- frontal, ethmoid, lesser wing of sphenoid
Damage to the anterior, middle and posterior fossa of the skull produce different symptoms.
Damage to which fossa produces these signs/symptoms?
- Battle’s sign (bruising behind ears)
- CN 9-12 palsy
- occipital
Posterior fossa!
How can you tell there is an orbital haematoma e.g. # of anterior and middle cranial fossa?
NB: it is hard to distinguish an orbital haematoma from a black eye…
- Subconjunctival haemorrhage (with no posterior limit)
- Absence of grazing of surrounding skin
- Confined to the margin of orbit (black eye involves surrounding cheek)
- Mild exophthalmos (anterior eye bulging)
- Degree of ophthalmoplegia
- Bilateral haematoma
A patient presents with nasal discharge that is
- Worse on bending forwards
- Doesn’t stiffen handkerchief’s/tissue
- Halo sign
- Can’t sniff it back up
What Ix should be done?
this is ?CSF rihinorrhoea
- Ix:
- Beta-2 transferrin level (gold standard)
- & glucose (bedside test) level (as after halo test e.g. just shows is CSF, glucose is also found in blood)
- –>Send to hospital
What is the worst type of shearing force and what does it cause?
rotational shearing forces (e.g. acel and decel) causes diffuse axonal injury
–> axon damage & rupture of small vessels
shearing through brainstem = fatal
How do you get “parenchymal contusion” of the brain define?
e.g. brain bruise
- this is focal rather than diffuse intra-axial problem
- e.g. parenchymal contusion = brain bruise
- –> focal injury can happen as brain hits the skull
-
get coup and contre-coup
- Coup: direct impact of brain on the skull at the site of injury e.g. frontal/ temporal lobes
- Contre-coup: injury from brain rebounding of opposite part of skull e.g. occipital lobe
- (e.g. as brain is like jelly in a solid box)
-
get coup and contre-coup
What can occur a spenoid ridge?
e.g. on sphenoid ridge can get:
Laceration within the skull -
- brain impinges on sharp of bony edge within the skull
Extra axial = lesions outside the brain
what can occur there for primary brain injury?
Bleeds!
- Cerebral oedema,
- ischaemia,
- infarction,
- herniation,
- hydrocephalus,
- SIADH
- cerebral salt wasting
are all types of what brain injury?
secondary brain inury!
- 1o brain injury occurs during initial insult e.g. intra- and extra-axial –> the displacement of physical structures of the brain
- vs
- 2o brain injury is NOT causes by by mechanical damage it –> it can result from 1o ijury or be independent of it… e.g.
- Cerebral oedema, ischaemia, infarction, herniation, hydrocephalus, SAH and traumatic brain injury
What type of secondary head injury is blown pupils a sign of?
Herniation
(e.g. apparently from uncal herniation - The key clinical sign of uncal herniation is ipsilateral oculomotor nerve palsy with a fixed and dilated pupil due to compression by the medial temporal lobe.)
After an intra-cerebral / intra-axial bleed what 2o injury can you get?
hydrocephalus
What 2o injury can traumatic brain injury lead to?
syndrome of inappropriate ADH (or anterior hypopituitarism, rarely)
–> causes retention of too much water & hyponatraemia
- Hyponatraemia due to SIADH commonly occurs after TBI, but is usually mild and transient.
- Chronic (dilution) hyponatraemia due to SIADH following TBI is a rare but important complication.
- It likely results from damage to the pituitary stalk or posterior pituitary causing inappropriate non-osmotic hypersecretion of ADH.
- NB: ADH is secreted from hypothalamus
what complication can sub arachnoid haemorrhage (1o injury comp.) lead to?
Cerebral salt wasting
- hyponatraemia
- extracellular fluid depletion due to inappropirate sodium wasing in the urine
How is cerebral perfusion pressure (CPP) defined?
cerebral perfusion pressure =
mean arterial pressure (MAP) - intracranial pressure (ICP)
What is cushings reflex?
the opposite of sepsis so is reflex INCREASE in BP and dc in HR
from
↑ICP + hypotension –> ↓cerebral blood flow → detected by cardiorespiratory centres in floor of 4th ventricle → the Cushing’s reflex - reflex increase in BP & bradycardia
What can be used to treat post traumatic cerebral oedema?
- Also (as well as inc. ICP and hypotension decreaseing cerebral BF –> cushings reflex to inc BP and bradycardia)
- hypercapnia causes cerebral vasodilation,
- –> in the presence of oedema this may further raise ICP
- & exacerbate brain injury
therapeutic hyperventilation & hypocapnia is used to treat post-traumatic cerebral oedema
What are the signs of all brain bleeds
e.g. including extradural, subdural, subarachnoid and intracerebral?
Cushing’s reflex:
- raised intracranial pressure,
- hypertension (to over come the high Cerebral perfusion pressure)
- reflex bradycardia (terminal sign :( - neither due to high BP triggering aortic arch baroreceptors or compressing intracranial vagal nerve)
Signs of raised intracranial pressure:
- papilledema on fundoscopy,
- pupil dilation (surgical oculomotor nerve palsy - normally constricts pupil)
What is an AVM?
aka Arteriovenous malformation?
- A Tangle of abnormal vessels
- range from telangiectasia –> cavernous & venous malformations
- often with arteriovenous fistulae;
- common over the distribution of the MCA
What problems/complications can an arteriovenous malformation cause?
- focal epilepsy,
- headaches,
- slowly progressive paralysis,
- SAH/intracerebral bleed
- Bruit can be heard over the eye, skull vault or carotid arteries
- Sturge-Weber syndrome:
- Cortical malformations
AVM can cause sturge-weber syndrome
- what is this?
-
port-wine stain
- localized to one or more segments of the cutaneous distn of the trigeminal nerve (V1,V2,V3)
- with corresponding extensive venous angioma; m
- ay cause contralateral focal fits
How do you investigate AVM?
cerebral angiography
(uses x ray and contrast to show blockages/other abnormalities in brain if cerebral etc)
What is the Rx for AVM?
- surgery OR
-
stereotactic radiography (gamma Knife)
- e.g. non-surgical radiation therapy used to treat functional abnormalities and small tumors of the brain. It can deliver precisely-targeted radiation in fewer high-dose treatments than traditional therapy, which can help preserve healthy tissue
Brain injury can result in abnormal posturing via damage to one or both corticospinal tracts or to the upper brainstem (e.g. midbrain and pons).
If there is damage to one or both corticospinal tracts (cortex–>LMN in spinal cord) what abnormal posturing do you get?
(in both of the damaged the ankles are plantarflexed and legs stiffly extended)
Decorticate
means flexors predominate in the upper limb
- arms are adducted, internally rotates and FLEXED to lie across chest
- wrist and fingers are flexed
- legs are stiffly extended
- ankles plantarflexed (pointed toes)
The lesion happening before the red nucleus = rubrospinal intact means flexors in upper limb predominate
Brain injury can result in abnormal posturing via damage to one or both corticospinal tracts or to the upper brainstem (e.g. midbrain and pons).
If there is damage to the upper brainstem e.g. midbrain and PONs what abnormal posturing do you get?
(in both of the damaged the ankles are plantarflexed and legs stiffly extended)
Decerebrate
(CENTRAL TEGMENTAL TRACT DAMAGE)
- damage to upper brain stem (midbrain, pons)
-
extensors predominate (vestibulospinal)
- Arms adducted, extended, internally rotated
- Wrists pronated & fingers flexed
- Legs stiffly extended
- Ankles plantar flexed
What does this CT scan show?
- Extradural haematoma
- Convex pool of bright white acute blood which does not cross the suture lines
- Can cause substantial midline shift
If you saw this CT what is the managment?
- NEUROSURGICAL EMERGENCY –> Mannitol IVI whole being transferred
- bone flap or burr-hole over suspected site,
- evacuate clot,
- control bleeding
- diathermy,
- silver clips,
- under-running
What does this CT scan show?
Subdural haematoma!
- Semilunar, crescentic collection
- bright white if acute blood – hypERdense,
- dark if chronic blood – hypOdense
- Blood can cross suture lines and cause midline shift
- NB: unlike extradural which cannot cross suture lines
You see a patient with this on their CTH, what is your management?
- Acute -
- release of clot through craniotomy but outcome poor due to severity of underlying brain trauma
- Chronic - (e.g. from elderly pt/anti coag small cerebral vein tear)
- release of clot or fluid collection through burr-holes
What does this CT scan show?
What Ix should be done?
- Bright white acute blood in the subarachnoid space,
- sulci and cisterns
- Often see hydrocephalus and some blood in the ventricles.
If there is Blood in ventricles & sulci – do LP 12hrs after onset if CT clear → xanthochromia (blood in CSF has yellow tinge)
What is the management of this CT?
(if aneurysm?)
(depends on cause of the SAH - AVM, dissection, vasculitis etc)
Until treated, strict bed rest, well controlled BP & avoid straining
- Intracranial aneurysms –> coil (minority require a craniotomy & clipping)
Main goal of surgery is to prevent re-bleeds:
-
Vasospasm prevention –> 21-day course of nimodipine 60mg 4hrly oral/ng (calcium channel blocker),
- also to prevent vasospasm = dont want hypervolaemia, induced-hypertension and haemodilution
- Hydrocephalus –> external ventricular drain or LT VP shunt
Rx hyponatraemia with fluid restriction
*re-bleeding is most worrying complication
What does this CTH show?
intracerebral haemorrhage
- Patches of bright white acute blood within the cortex
- which are well demarcated and odd shapes
- Can see intraventricular extension of bleeds
A pt has this CT head and presents with
Progression of syx over minutes to hours: impaired consciousness, focal neurology (e.g. hemiplegia), headache, nausea and vomiting . What is the Rx?
for intracerebral bleed: Optimise physiology –>
Surgical Rx: young, superficial bleeds, // critically raised ICP, major deficit
- CBM - brainstem compression, hydrocephalus - SURGERY, pts do well :)
- Lobar -surgery SIMPLER
- :( –>
- Brainstem - very bad will probably will die anyway
- Basal Ganglia –> too much eloquent brain to go through
