Traumatic Brain Injury Flashcards
Are CT’s contrast or non-contrast in head injury?
Non-contrast
Steps in CT interpretation?
1) Name & DOB
2) When was scan done?
3) Previous CTs to compare?
4) Is falx cerebri (line in middle) in a straight line?
5) What do ventricles look like?
Black vs white on CT?
Black - low density (air)
White - high density (blood, bone)
Acute vs chronic bleediong?
Acute - hyperdense (white)
Chronic - hypodense (dark grey)
What are the 2 overall types of intracranial haemorrhages?
1) Extra-axial:
- extradural
- subdural
- subarachnoid
2) Intra-axial:
- intraparenchymal
- intraventricular
Location of extradural haemorrhage?
Collection of blood between skull and dura mater
Typical cause of extradural haemorrhage?
Low impact trauma, typically to temporal region (pterion).
Rupture of middle meningeal artery.
Presentation of extradural
1) General: headache, N&V, progressive drowsiness
2) Lucid interval
3) Fixed dilated pupil (due to CN III palsy)
CT findings in extradural haemorrhage?
- Hyperdense = acute
- Mass effect possible (shift of midline)
- Biconvex/lentiform shape
- Limited by suture lines of skull
Mx of extradural haemorrhage?
Neurosurgical opinion –> conservative or surgical
Location of subdural haemorrhage?
Deep to the dura mater of the meninges and superficial to the arachnoid mater.
Acute vs chronic subdural haemorrhage?
Acute: develops within 48h of injury
Chronic: develops over 3 weeks
What are some behavioural features seen in subdural haemorrhage?
Memory loss, personality changes, cognitive impairment.
Can mimic dementia.
Fluctuating over weeks/months.
Mechanism of injury in acute subdural haemorrage?
High impact trauma
CT findings in acute subdural haemorrhage?
- HYPERdense (acute bleed)
- Mass effect possible
- Crescent shaped collection
- NOT limited by suture lines
Important to consider in patient history with any head injury?
Are they on any anticoagulants?
Cause of chronic subdural haemorrage?
Rupture of small bridging veins (between venous sinus & cortex)
Risk factors for chronic subdural haemorrhage?
Eldery, alcohol abuse
CT findings in chronic subdural haemorrhage?
- HYPODense
- Midline shift possible
- Crescent shaped collection
- Not limited by suture lines
CT findings in acute on chronic subdural haemorrhage?
- Hypodense
- Hyperdense
- Midline shift possible
- Crescent shaped collection
- Not limited by suture lines
i.e. both
Mx step in all traumatic brain injuries?
Referral to neurosurgery
What is the most important initial treatment in SAH?
Nimodipine
Role of nimodipine in SAH?
Prevent vasospasm (can lead to ischaemia)
Location of SAH?
Between pia and arachnoid membranes
What is the subarachnoid space normally occupied by?
CSF
What is most common cause of spontaneous SAH?
Saccular (berry) aneurysm
Risk factors for berry aneurysms?
- FHx
- Female
- African descent
- PKD
- Connective tissue disorders
3 key ECG findings in SAH?
1) Tall peaked T waves
2) ST depression
3) Prolonged QT
CT findings in SAH?
- Hyperdense
- Distributed in cisterns and sulci
- Intraventricular involvement
Stepwise investigations in SAH?
1) Non-contrast CT head
a) If positive –> diagnose SAH
b) If negative <6h after bleed –> think about other diagnoses
c) If negative >6h after bleed –> consider LP
2) LP at least 12 hours after symptoms onset:
a) If negative –> thhink about other diagnoses
b) if positive (elevated bilirubin/xanthochroma) –> diagnose SAH
3) Get CT angiography of head
Mx of vasospasm in SAH?
Nimodipine
What electrolyte abnormality is common in SAH?
Hyponatraemia
Mx of seizures in SAH?
Prophylactic levetiracetam
Mx of hydrocephalus in SAH?
Drain/shunt
Mx of re-bleeding in SAH?
Regular neuro obs
Repeat CT
Head injury rules: CT <1 hour?
1) GCS <13 on initial assessment
2) GCS <15 2 hours post-injury
3) Suspected open or depressed fracture
4) Basal skull fracture
5) Post-traumatic seizure
6) Focal neuro deficit
7) >1 episode of vomiting
Head injury rules: CT <8 hours?
1) Warfarinised
2) LOC/amnesia +
- 65+ years
- bleeding/clotting disorder (or anticoagulants)
- dangerous mechanism of injury
- >30 mins retrograde amnesia
