Head Injury

Question 1

Neurological Injury

Answer 1

Primary injury
Secondary injury

Question 2

Secondary brain injury

Answer 2

Inadequate cerebral oxygen delivery
- Systemic - shock, respiratory failure
- Intracranial - reduced cerebral perfusion pressure

Herniation syndrome

Question 3

Treatment of raised ICP with herniation

Answer 3

1. Mannitol - should not be given prior to evacuation of haematoma unless signs of deterioration unrelated to Systemic deterioration

Give after volume resuscitation

Mannitol draws fluid out from the brain to reduce ICP
May lose tamponade effect - worsened bleeding
Severe hypotension

2. Hyperventilation
   PaCO2 < 35mmHg - not carried out routinely
   Vasoconstriction -> compromise cerebral blood flow

Question 4

Sedation and neuromuscular blockage

Answer 4

Sedation reduces cerebral oxygen demand
Prevents coughing - cough increases ICP

Question 5

Role of tranexamic acid

Answer 5

1g over 10 mins then 1g over 8 hours

Given within 3 hours of injury
GCS < 12
ICB on CT brain

Question 6

Prevention of herniation

Answer 6

ICP threshold 20-25mmHg
CPP < 60mmHg

Question 7

Reduce ICP

Answer 7

Drain CSF via EVD
Osmotherapy
PaCO2 35mmHg
Improve venous drainage
- Nurse 30 degree head up
- Head and neck position neutral - ensure venous drainage not obstructed

Decrease cerebral oxygen demand
- Treat fever
- Prevent seizures - Keppra

Question 8

Management of status epilepticus

Answer 8

IV lorazepam 0.1mg/kg or IM midazolam 10mg
Alternative diazepam 0.1-0.2mgkg

Phenytoin 15-20mg/kg

RSI
- thiopentone/propofol
- Sux/rocuronium
(NM agent may cause rhabdomyolysis)

Question 9

Propofol

Answer 9

Loading 3-5mg/kg
Infusion 30-100 mcg/kg/min

Propofol infusion syndrome
Rhabdomyolysis
Severe matbolic acidosis