Head Injury

Question 1

What is the difference between primary + secondary brain injury due to head injury?

Answer 1

Primary: neuronal damage occuring at time of injury (unpreventable)
Secondary: occurs due to consequence of injury (partly preventable) e.g. oedema, haemorrhage

Question 2

What is the normal range for adult intracranial pressure?

Answer 2

9-11 mm Hg

Question 3

What does a patient with an anterior cranial fossa fracture look like? (buzzword)

Answer 3

Racoon/panda eyes

Question 4

What does a patient with a middle cranial fossa fracture look like? (buzzword)

Answer 4

Battle sign bruising over mastoid area

Question 5

A coma equates to what score on the Glasgow Coma Score? What are the other features that must be present in coma?

Answer 5

8 or less

No eye opening, no obeying commands, no speech

Question 6

When should a CT scan be requested in head trauma?

Answer 6

Any one of the following:
Suspected skull fracture
GCS less than 15 (not orientated)
Focal neurological signs
Taking anticoagulants

Question 7

List intensive care management of head injury

Answer 7

Sedation
Ventilation
BP management
Glucose maintenance
Temperature maintenance

Question 8

How does sedation help in management of head injury?

Answer 8

Reduces cerebral metabolic rate, blood flow and ICP

Question 9

What are the two types of head injury?

Answer 9

Open (penetrating, missile)

Closed (non-missile)

Question 10

Closed head injury can be split into three types depending on direction of force. What are they?

Answer 10

Acceleration
Deacceleration
Rotation

Question 11

Define Monro Kielle Hypothesis

Answer 11

Skull is a closed box structure with limited expansion in response to pressure

Question 12

How is cerebral perfusion pressure calculated?

Answer 12

MAP - ICP

Question 13

What CPP is aimed for after a head injury?

Answer 13

> 60 mmHg

Question 14

What type of cerebral autoregulation is damaged in trauma?

Answer 14

Focal cerebral autoregulation

Question 15

Describe what is meant by ‘ischaemic penumbra’

Answer 15

Ischaemic but still viable cerebral tissue (typically surrounds dense ischaemic core)

Question 16

What physical findings might you expect after head injury?

Answer 16

Scalp swelling/ laceration
Skull vault fracture
Skull base fracture

Question 17

What are the three main areas tested in the Glasgow Coma Scale?

Answer 17

Eye opening
Verbal response
Best motor response

Question 18

What is the function of the GCS?

Answer 18

To assess consciousness

Question 19

What is the range of scores you can achieve in the GCS?

Answer 19

3 - 15

Question 20

What score on the GCS is typically achieved in mild head injury?

Answer 20

13 - 15

Question 21

What are the main 3 causes of mortality in coma as a result of head injury?

Answer 21

Hypoxia
Hypotension
Raised ICP

Question 22

List the main pathology associated with traumatic intracranial bleeding

Answer 22

Extradural haematoma
Subdural haematoma
Intracerebral haematoma
Traumatic SAH

Question 23

List management options to treat raised ICP

Answer 23

CSF drain
Mannitol
Hyperventilation
Hypothermia
Decompressive craniectomy

Question 24

What is the mechanism of action of mannitol in treating raised ICP?

Answer 24

Increases microperfusion
Reduce oedema (acts as a diuretic)

Question 25

List the potential late effects of head injury

Answer 25

``` Post-traumatic epilepsy CSF leakage (into nose or middle ear) Cognitive problems ('post-concussive syndrome') ```

Question 26

List the 5 levels of the Glasgow outcome scale

Answer 26

1. Dead 2. Persistent vegetative state 3. Severely disabled 4. Moderately disabled 5. Good recovery

Question 27

Define 'vegetative state'

Answer 27

Sleep wake cycles are preserved but no other interaction - e.g. eye tracking, response to stimulation

Question 28

List the characteristic clinical finding on CT scan found in extradural haematoma?

Answer 28

Hyperdense lens-shaped lesion

Question 29

List the characteristic clinical finding on CT scan found in subdural haematoma?

Answer 29

Crescent-shaped 'banana' lesion (acute: hyperdense, chronic: hypodense)

Question 30

What are the clinical symptoms of extradural haematoma?

Answer 30

Typically young person whol falls and hits head Brief loss of consciousness followed by an interval and then symptoms - headache, V, CL hemiparesis, IP pupillary dilatation

Question 31

What are the clinical symptoms of subdural haematoma?

Answer 31

Typically, elderly person who falls or NAI Acute - reduced consciousness Chronic - increasing loss of consciousness, headaches, confusion, weak, seizure, gait abnormality, cognitive impairment

Question 32

What is the classical origin of extradural haematoma?

Answer 32

Middle meningeal artery

Question 33

What is the classical origin of subdural haematoma?

Answer 33

Cerebral bridging veins