Head Trauma And Acute Intracranial Events

Question 1

What are the two types of primary head trauma?

Answer 1

Focal and diffuse

Focal- haematoma- extradural, subdural, intracerebral. Contusion- coup/ contracoup.

Diffuse- concussion, diffuse axonal injury.

Question 2

What is a cerebral contusion?

Answer 2

Bruising of brain where blood mixes with cortical tissue due to microhaemorrhages and small vessel leaks.

Question 3

What is the pathophysiology of a cerebral contusion?

Answer 3

Trauma —> microhaemorrhages—> cerebral contusin—> cerebral oedema—> raised ICP—> coma

Question 4

What is the difference between a coup and contracoup cerebral contusion?

Answer 4

Coup= damage caused at site of injury

Contra coup= damage caused at opposite side to injury due to bouncing of brain in skull

Question 5

What is concussion?

Answer 5

Head injury with temporary loss of brain function

Question 6

What is the pathophysiology of concussion?

Answer 6

Trauma—> stretching and injury to axons—> impaired neurotransmission, loss of ion regulation, reduction in cerebral blood flow= temporary brain dysfunction.

Question 7

What is post concussion syndrome?

Answer 7

Difficulty in thinking clearly and concentrating

Physical- headache, nausea, vomiting, balance problems

Emotional- irritability, sadness, nervousness

Sleep disturbance sleeping more or less than usual

Question 8

What is diffuse axonal injury?

Answer 8

Shearing of interface between grey and white matter following traumatic acceleration/ decceleration or rotational injuries to brain. This damages intracerebral axons and dendritic connections

Question 9

What are the clinical signs of basilar skull fracture?

Answer 9

Raccoon eyes
CSF rhinorrhea
CSF otorrhea
Battle sign
Haemotympanum
Haematoma.

Question 10

What are the urgent CT head criteria?

Answer 10

Consciousness- GCS < 13 at any point
GCS < 14 , 2 hours after injury.

Neurological abnormality eg focal neurological deficit, seizure or LOC with age>65, coagulopathy, mechanism of injury, antegrade amnesia

Suspected skull fracture

Discrete episodes of vomiting

Question 11

What is the management of extra dural haemorrhage?

Answer 11

If small- can be observed and managed conservatively with neurological follow up.

If large- needs craniotomy and clot evacuation.

Question 12

What are the complications of extra dural haemorrhage?

Answer 12

Permanent brain damage
Coma
Seizures
Weakness
Pseudoaneurysm
Arteriovenous fistula.

Question 13

In what situation is acute sub dural haemorrhage most common?

Answer 13

In head trauma.

Question 14

In what situations is subacute or chronic sub dural haemorrhage common?

Answer 14

In elderly with vague or absent history of head trauma.

Question 15

How do acute bleeds appear on CT head?

Answer 15

Hyper dense i.e brighter than brain tissue

Question 16

How do chronic bleeds appear on CT head?

Answer 16

Darker than brain tissue.

Question 17

Where does blood collect in subarachnoid haemorrhage?

Answer 17

Between arachnoid and pia mater

Question 18

How do patients with sub arachnoid haemorrhage commonly present?

Answer 18

Sudden onset thunderclap headache

Meningism
N+V
Fever
Focal neurological deficits
LOC

Question 19

What factors can increase the risk of a berry aneursym?

Answer 19

Family history of them
Hypertension
Heavy alcohol consumption
Abnormal connective tissue disorders eg autosomal dominant polycystic kidney disease, ehlors danlos, neurofibromatosis, marfans disease.

Question 20

Where do berry aneurysms most frequently occur?

Answer 20

At the junction of the anterior cerebral artery and the anterior communicating artery.

Question 21

What changes in the CSF will be detected in SAH ?

Answer 21

Presence of RBCs

Xanthochromia- RBCs break down to make a yellowy substance.

Question 22

What management is required for a patient with SAH?

Answer 22

Stabilise the patient
Prevent rebleeding
Treat cerebral vasospasm (can cause ischaemia in rest of brain)
Correct hyponatraemia
Neurosurgical intervention if large bleed.