NEUROTRAUMA Flashcards
what is a traumatic brain injury?
A traumatic brain injury is a form of acquired injury that occurs from a sudden trauma or impact that causes direct damage to the brain.
what might cause a TBI?
It can result when the head suddenly and violently hits an object, or when an object pierces the skull and enters the brain tissue
eg. falls, motor vehicle accident, violence, sporting injuries, bomb blast
Identify the different areas of the brain a TBI may affect and state what functions may be affected
Brain stem: changes in HR, breathing, BP, vomiting and swallowing, digestion
Cerebrum: intelligence, learning, judgement, speech and memory, sense of learning, vision, skeletal muscle movements
Cerebellum: balance and coordination and posture
How are TBIs categorised?
- Mild: GCS 13-15, slight nausea, confusion
- Moderate: GCS 9-12, amnesia
- Severe: GCS <8, poor patient outcomes, secondary brain injury
identify the types of TBI (6)
- concussion
- diffuse axonal injury
- epidural.extradural haematoma
- subdural haematoma
- subarachnoid haemorrhage
- cerebral contusion
describe a concussion
- a blow to the head.
- It is a diffuse injury that is not seen under a scan due to the microscopic bleeding in the brain.
- Result of an acceleration or deceleration injury causing transient amnesia and LOC coupled with N&V and headache.
describe a diffuse axonal injury
- microscopic shearing and tear of the brain’s axons causing them to shift and rotate within the skull.
- This injury causes microscopic bleeding.
- DAI can only be diagnosed with MRI.
describe an epidural/extradural haematoma
- a focal injury that is seen under a CT scan.
- It is bleeding that occurs between the skull and dura mater, commonly from a torn meningeal artery at the pterion region (they bleed quick) → onset of symptoms is rapid including headaches, reduced LOC, hypertension and a decrease in heart rate (cushing’s syndrome).
- Since the bleed is restricted by the sutured line of the skull, there is an increase in ICP.
describe a subdural haematoma
- bleeding into the subdural space due to a rupture of bridging veins (bleeds slow).
- This rupture of the parenchymal vessels can cause LOC, hemiparesis and dilated/fixed pupils. → since the bleed is not restricted by suture lines, the bleeding can spread over a larger surface area of the brain.
- Onset of symptoms is slower.
describe a subarachnoid haemorrhage
- bleeding into the subarachnoid space generally from a weak blood vessel bursting, usually caused spontaneously or by an aneurysm.
- Blood causes increased pressure on the brain
describe a cerebral contusion
- scattered areas of bleeding on the surface of the brain.
- This type of BI is most likely to cause disability and death.
what is the Munroe Kellie doctrine?
Swelling occurs due to an increase in the CFS, blood and brain tissue. There are equal parts of said components within the brain so an increase in blood will cause an increase in pressure → this pressure causes the brain stem to compress which then impacts individuals HR and breathing leading to eventual brain death due to the pressure.
So if one component increases, the other two decrease.
→ the theory explains the relationship between the 3 cranial constituents found in the fixed compartment of the skull that maintains intracranial pressure. These include the blood, cerebral spinal fluid (CSF), and brain tissue. The theory states that if one of these constituents increases in volume, then the other two will decrease and therefore increases ICP.
what is a secondary brain injury and how are they caused?
SBI is the result of a primary injury and the body’s response to that injury.
It is the changes that occur to the brain over a period of time post-primary injury.
Factors that can cause secondary brain injury are hypoxia and hypotension.
what nursing interventions might prevent secondary brain injury?
→ A-G assessment + cervical spine stabilisation.
→ adequate oxygenation
→ administer IV fluids to maintain BP
→ maintain normocapnia (ensure the airway is patent/considered mechanical ventilation).
→ GCS assessment
→ maintain SBP above 90mmHg
how can primary and secondary brain injury be prevented?
Prevent primary by not engaging in risk-taking behaviours that increase one’s likelihood of sustaining a brain injury
To prevent secondary brain injury prevent hypoxia, hypotension and hypercapnia (elevation of arterial carbon dioxide tension)
