Traumatic Brain Injury Flashcards
How do we grade TBI?
Mild: transient lossof consciousness/confusion
Moderate:loss of consciousness (15 min-6hour)
Severe: >6 hour :LOC
What are some long term consequences of MILD HEAD INJURY?
15% of mild TBI will experience
- nausea, diziness
- subtle but potentially disabling changes- memory problems, impaired concentration, extreme tiredness, other minor cognitive deficits, emotional lability/disinhibition
What are the outcomes of MODERATE HEAD INJURY?
On going dysfunction in consequence
- physical: headaches, diziness, extreme tiredness
- Cognitive: deficits in memory, functions, attention, concentration and language (word finding). Will depend on cortical area damaged
- Behavioural: irritability, anxiety, disinhibition, emotional lability
What are the outcomes of severe head injury?
– Persistent vegetative state
– Severe physical, cognitive and behavioural problems
– Typically require constant care
What are the 3 types of head injury?
I. Penetrative Head Injury - penetration of the skull and/or brain by an external object (e.g. missile).
II. Closed Head Injury - acceleration, deceleration and rotational forces to the head that cause movement of the brain within the skull.
III. Crushing Head Injury - caught between two hard objects
What is the most common form of TBI?
Closed head injury - Relates to forces that affect the brain • Acceleration/deceleration • Rotational/angular • Propagation of shock wave Head impact may or may not occur
Fixed surface closed head injury- where will damage be?
Coup: area first impacted, then contracoup-= where brain bounces back to other side of skull going to be damaged
Shearing forces throughout entire brain
Subdural veins torn as the brain rotates
Damage to temporal bone from rough bones at the base & damage to brain stem - causing swelling etc.
Lesions can be focal or diffuse- explain
• Focal – contusions – lacerations – skull fracture • Diffuse (occur immedialtey or develop over time) – axonal injury – neuron degeneration – micro-haemorrhages
wht are FOCAL CONTUSIONS
Pattern of superficial bruises on outside surface of brain.
Largely about brain moving within skull cavity and impacting within the skull.
Contusions can become haemorrhagic, contributing towards swelling of brain, ICP
What are FOCAL lacerations?
Tearing of brain (typically frontal and temporal lobes) as brain rotates across ridges inside the skull.
• May also lead to significant tearing of blood vessels.
Explain some sensory damage which can occur secondary to TBI? (9)
- Brain swelling/edema
- Haemmorhage
- Increased intracranial pressure
- Mass effects/ herniation
- Excitotoxicity due to excess neurotransmitters • Infection
- Epilepsy
- Ischemia/hypoxia/free radicals
- Diffuse axonal injury
what is an intra cranial haemorrhage? what can it cause? what are the types?
Bleeding in and/or around the brain. May lead to ‘mass effect’ = cerebral compression and herniation
• Epidural hematoma
– torn vessels under the skull
• Subdural hematoma
– usually tearing of veins in subdural space
• Subarachnoid haemorrhage
• Intra-cerebral or cerebellar hematomas
– Tearing of vessels in brain parenchyma
When would you get an epidural haematoma?
Almost always result of skull fracture
• Typically rupture of middle meningeal artery (under temporal bone) or damage to a sinus
• Hematoma may cause increased ICP, compression/herniation of brain
• Often a ‘lucid’ period between initial injury and subsequent deterioration due to accumulation of blood
What is a subdural haematoma?
Tearing of veins where they penetrate the dura • Acute and chronic forms
- > Acute usually follows severe head injury, involves rapid functional deterioration
- > Chronic forms may involve minimal injury - slowly increasing size of hematoma and consequent increased ICP
What is battered child Syndrome?
What would you see pathologically?
Clinical manifestations
– Irritable, refuse eating, vomiting, seizures
• Common pathological changes
– Subdural haemorrhage, shearing changes, diffuse cerebral edema
(+mass effect), retinal haemorrhage