Traumatic brian injury Flashcards
insteda of concussion what should we use?
Traumatic brain injury then classify severity according to Mayo criteria
what are important aspects of TBI hx?
- ABCDE (FG) – ATLS GUIDELINES
- Mechanism of injury? Speed? Magnitude of impact? Seatbelt? Airbag?
- Think about underlying cause (consider seizures/cardiac event)
- Loss of consciousness?
- Cognitive/behavioral change (may need a collateral history)
- Focal neurological symptoms/signs
- Past medical history (e.g. epilepsy, pre-existing cognitive impairment)
- Drug history (prescribed and non-prescribed)
- ANTICOAGULANT/ANTIPLATELET (“blood thinners”) history vital
what is classified as mild TBI?
Mild (Probable) TBI:
– Loss of consciousness < 30 minutes
– Post-traumatic amnesia < 24 hours
– Depressed, basilar or linear skull fracture (dura intact)
what constitutes mod-sev TBI?
Moderate–Severe (Definite) TBI – Death due to this TBI – Loss of consciousness > 30 minutes – Post-traumatic amnesia >24 hours – Worst GCS <13
– One or more of the following present (usually on imaging): Intracerebral
haematoma; Subdural haematoma; Epidural haematoma; Cerebral contusion;
Haemorrhagic contusion; Penetrating TBI (dura penetrated); Subarachnoid
haemorrhage; Brainstem injury
what are the features of a possible TBI?
(Possible) TBI: – Blurred vision – Altered mental status – Dazed – Dizziness – Focal neurological symptoms – Headache – Nausea
what is post traumatic amnesia?
Transient state of altered brain function that occurs following a TBI
• Typified by episodic memory impairment, behavioral change also common
• Should be quantified e.g. Westmead PTA scale
define contre coup injury
when the trauma is on one side of the head but injury is on the opposite side
what are common issues following TBI?
Headache - medication overuse/migraine • Visual disturbance - double vision e.g. IVth nerve palsy • Cognitive and behavioral problems (pre-existing cognitive/psychiatric problems often missed during trauma call)
• Loss of insight/capacity – DOLS may be required • Dizziness – BPPV • Sleep disruption/fatigue • Seizures • Taste/smell/hearing problems
• Neuropsychiatric symptoms – depression, PTSD, anxiety, hallucinations (rarely), substance abuse • Neuroendocrine disturbance – DI, growth hormone def., sexual dysfun
how do we manage TBI?
Refer to TBI clinic
Headaches - treat as migraine
Epilepsy - anti-epileptics
Depression - as usual
BPPV - repositioning manœuvres
MDT involvement!
people who suffer a TBI are particularly at risk from?
Diffuse axonal injury (DAI) - due to shear forces
associated with poor long term outcomes
where do the cranial nerves originate?
brainstem
1st four - from midbrain
2nd four - pons
last four - medulla
how do we test visual acuity
distant vision - snellen chart
near vision - near reader guide
how do you test visual acuity
you have to cover your eye too?
what do the pupillary reflex test for
relative afferent pupillary reflex - preserved eye constricts, affected pupil dilates (or remains dilated)
as part of CN 3,4,5 what else do we test?
saccadian persuit eye movements
what signs may we see in test of CN 3,4,5 in disease processes?
MS - ask them to loof left. abducting nystagmus on the left. slow medial rectus (so slower moving left) - due to intraoptic opthalmoplegia
PSP - difficulty with upward gaze
list disorders of eye movement
3rd nerve palsy -
- eye moves down and out (because doesnt innervate thes muscles - LR6SO4),
- ptosis (as innervates LPS),
- dilated pupil - beecause 3rd nerve carries sympathetic fibres that dilate the pupils
horners syndrome sx? cause?
due to disruption of sympathetic fibres - slightly diff from 3rd nerve palsy bcos constricted pupil
Constricted pupil (miosis),
drooping of the upper eyelid (ptosis),
absence of sweating of the face (anhidrosis),
sinking of the eyeball - means eyeballs look smaller (enophthalmos).
how do we test the corneal reflex
touch the cotton wool onto the pupil - thats where the cornea is
which muscles does CN7 supply?
muscles of facial expression
what are the types of face palsies?
UMN nerve palsies - affects lower part so upper part spaired eg stroke
LMN nerve palsies - affects all muscles eg Bells palsy
apart from taste and muscle movement, what else is CN7 responsible for?
supplies stapedius - causes hyperacusis in palsies
what could cause a brisk gag reflex?
pseudobulbar palsies eg in MND
