Traumatic brain and head injury

Question 1

What is traumatic brain injury (TBI)?

Answer 1

A non-degenerative, non-congenital insult to the brain from an external mechanical force, possibly leading to temporary or permanent impairment of cognitive, physical and psychosocial functions.

Question 2

High risk groups for brain injury?

Answer 2

• Young men and elderly
• Previous head injuries
• Residents of inner cities
• Alcohol and drug abuse
• Low income

Question 3

Mechanisms of injury?

Answer 3

• Assault
• Falls
• RTC’s (road traffic collisions)
• Sports
• Over 1/2 involve alcohol

Question 4

What is the importance of managing ICP?

Answer 4

• Munro kellie principle states that the sum of volumes of the brain, cerebrospinal fluid (CSF) and intracereberal blood is constant.
• An increase in one should cause a decrease in return in either one or both of the remaining two.
• Decrease in space for brain within the skull leading to herniation.

Question 5

What is diffuse axonal injury?

Answer 5

• Severe form of traumatic brain injury due to shearing forces.
• Occurs where the density difference is greatest (grey/white interface)
• Excitotoxicity and apoptosis
• Inflammatory mediator release

Question 6

Extradural (epidural) haematoma on CT scan and features?

Answer 6

“Lemon” shaped

• Injury with loss of consciousness
• Recovery “lucid interval”
• Rapid progression of neurological symptoms

Question 7

Acute subdural haematoma presents with a crescent (“banana”) shape and is dark/black on CT scan. True/false?

Answer 7

False

Acute subdural haematoma - crescent (“banana”) shape and white on scan

Chronic subdural haematoma - crescent (“banana”) shape and dark/black on scan

Question 8

What features confirm brainstem death and what are the associated cranial nerves?

Answer 8

• No pupil response (CN 2,3)
• No corneal reflex (CN 5, 7)
• No motor response (CN 5, 7)
• No vestibulo-ocular reflex (CN 3, 6, 8)
• No gag/cough reflex (9, 10)
• No respiration (apnoea test)

Question 9

What is primary goal of management?

Answer 9

To control ICP (intracranial pressure)

Question 10

What can be done to control ICP?

Answer 10

• Surgical management
• Intubated and ventilated, sedated.
• Maximise venous drainage of the brain - head of bed tilt, cervical collars
• CO2 control
• Osmotic diuretics – mannitol, hypertonic saline
• CSF release
• Decompressive craniectomy

Question 11

What else is important for management?

Answer 11

Nutrition