5. a. Head Injuries

Question 1

What effects does an uncal herniation have?

Answer 1

CN3: dilated pupil
PCA: stroke
Corticospinal tract in midbrain: contralateral hemiparesis
Eventually results in ipsilateral weakness

Question 2

What effect does a subfalcine herniation have?

Answer 2

ACA: weakness in leg

Question 3

What effect does a transforaminal herniation have?

Answer 3

Cushing response

• Raised ICP
• Bradycardia
• erratic breathing

Question 4

What is the mechanism of the Cushing response?

Answer 4

Herniation puts pressure on the brainstem, causing hypoxia in the central chemoreceptors
BP is increased to increase perfusion, and due to high BP baroreceptors in the CVS cause reflex bradycardia
Pressure on the medulla causes erratic breathing

Question 5

How is cerebral perfusion calculated?

Answer 5

MAP-ICP

Question 6

How is MAP calculated?

Answer 6

Diastolic + 1/3pulse pressure

Question 7

What are the systemic causes of secondary brain injury?

Answer 7

Hypoxia, hypercapnia
Hypotension
Hyperthermia
Poor glycaemic control

Question 8

What are the intracranial causes of secondary brain injury?

Answer 8

Brain swelling
Brain shift and herniation
Raised ICP
Post-traumatic fits
Infection

Question 9

What is the treatment for extradural or acute subdural haematoma?

Answer 9

Emergency craniotomy

Question 10

How is chronic blood differentiated from acute blood in a subdural haematoma?

Answer 10

Acute is whiter

Question 11

What patient groups are chronic subdural haematomas seen in?

Answer 11

Elderly, anticoagulants, alcoholism

Question 12

What is the treatment for a chronic subdural haematoma?

Answer 12

Burr hole drainage

Question 13

What is the treatment for an intracerebral haematoma?

Answer 13

Usually conservative as blood can be resorbed

Evacuate the haematoma if raised ICP or midline shift

Question 14

When should a diffuse axonal injury be suspected?

Answer 14

Prolonged unconsciousness without a mass lesion

Question 15

What is the macroscopic appearance of the brain in diffuse axonal injury?

Answer 15

Ventricles compressed

Sulci visible

Question 16

What is the treatment for a diffuse axonal injury?

Answer 16

Conservative

Decompressive craniectomy

Question 17

What are the stages for eyes in the Glasgow coma scale?

Answer 17

1. does not open
2. opens to pain
3. opens to command
4. opens spontaneously

Question 18

What are the stages for verbal response on the Glasgow coma scale?

Answer 18

1. no speech
2. incomprehensible sounds
3. inappropriate words
4. confused speech
5. orientated

Question 19

What are the stages for motor response on the Glasgow coma scale?

Answer 19

1. no movement
2. extension to pain
3. abnormal flexion to pain
4. normal flexion to pain
5. localises to pain
6. obeys commands

Question 20

What is the management of raised ICP?

Answer 20

Keep head at 30 degrees
Mannitol and furosemide (avoid low vol)
Hypertonic saline
Sedation, analgesia
Induce hyperventilation and hypothermia

Question 21

What is the surgical management of raised ICP?

Answer 21

ICP bolt to monitor pressure
Surgical removal of pathology
External ventricular drain
Decompressive craniectomy