Pathophysiology of Traumatic Brain Injury Flashcards
1
Q
Causes of traumatic brain injury
A
RTA in small animals - common in first opinion practice
Horses hitting their heads when rearing - equine practice
Severe head trauma is associated with high mortality
2
Q
Considerations when dealing with TBI
A
- Dogs and cats have a remarkable ability to compensate for loss of cerebral tissue
○ Important not to reach hasty prognostic conclusions based on initial appearance
○ Many pets go on to have a functional outcome and recover from injury - Guidelines for management in people:
○ Focuses on maintaining adequate cerebral perfusion
3
Q
Primary Injury
A
- Physical damage caused by the trauma
- Causes haemorrhage and oedema
- Little we can do about this
4
Q
Secondary damage
A
- Damage caused by:
○ Excitatory neurotransmitters
○ Reactive Oxygen Species (ROS)
○ Pro-inflammatory cytokines
5
Q
What can secondary damage lead to?
A
- Cerebral oedema formation
- Increased intracranial pressure
- Compromised blood-brain barrier
- Alterations in cerebrovascular reactivity
6
Q
What is the most common/deadly sequel to secondary injury?
A
Increased intracranial pressure
7
Q
Increased intra-cranial pressure
A
- Common and potentially deadly sequel to traumatic brain injury
- Brain swells
- Reduced blood flow
- Oxygen and nutrient deprivation
Reduced perfusion
8
Q
Systemic contributions to secondary brain injury
A
○ Hypotension
○ Hypoxia
○ Hypo/hyperglycaemia
○ Hypo/hypercapnia
○ Hyperthermia
9
Q
Patient Assessment and Management
A
- Always treat the whole animal first
○ Manage hypovolaemia and hypoxaemia to help reduce ICP - Modified Glasgow Coma Scale (MGCS) for veterinary use
○ Evaluated with respect to survival over 48 hour period
○ Higher score = better prognosis
○ Level of consciousness is most reliable measure of impaired cerebral function
May appear impaired if in pain or on analgesia
