Flashcards in 10. Head trauma & acute intracranial events Deck (8):
What is the difference between primary and secondary brain injury?
Primary: induced by mechanical force and occurs at moment of injury, e.g. axonal shearing.
Secondary: occurs some time after primary impact, not as a result of the trauma but of complications, e.g. hypoxia. intracranial hypertension. Can be attenuated or prevented by appropriate treatment.
What are the 2 main types of primary brain trauma?
- haematoma (extradural, subdural, intracerebral)
- contusion (coup and countre-coup)
- diffuse axonal injury
What is cerebral contusion - how does it occur?
- "Bruising" of the brain (blood mixes with cortical tissue) due to microhaemorrhages caused by trauma.
- Often involve coup/contre-coup trauma where brain is injured directly under area of impact as well as opposite side (due to rebound against opposite cranial wall).
Which parts of the brain are at particular risk of contusion?
Inferior frontal and temporal lobes due to collision with bony protuberances in middle cranial fossa and roof of ocular orbit - can cause attention, emotional and memory problems.
What is concussion? What are the symptoms?
Head injury involving temporary loss of brain function due to stretching and injury to neuronal axons (mild form of DAI). Results in:
1. impaired neurotransmission
2. loss of ion regulation
3. reduction in cerebral blood flow
Symptoms usually appear mins-hrs post trauma:
1. persistent headache
3. nausea and vomiting
4. confusion, loss of memory
5. vision problems
6. irritability, anxiety
Describe a possible complication of concussion.
Post-concussion syndrome - set of symptoms that persist from weeks to a year or more after a concussion.
- Cognitive: difficulty thinking, concentrating and memorising
- Physical: headache, balance problems, dizziness, fatigue, vision problems
- Emotional: irritability, anxiety
- Sleep disturbance
What is diffuse axonal injury? Why is this serious?
Shearing of interface between grey and white matter following traumatic acceleration/deceleration or rotational injuries to the brain, damaging the intra-cerebral axons and dendritic connections.
Frequently associated with cerebral oedema and RICP... risk of herniation... progression to coma and death.