Neurological emergencies
Head injury
• 32 year old man
• Assaulted
• Unconscious
Management?
Image  Kathy Mak
Neurological injury
• Primary injury
• Secondary injury
Secondary brain injury
• Inadequate cerebral oxygen delivery
– Systemic
• Shock
• Respiratory failure
– Intracranial
•  cerebral perfusion pressure
• Herniation
Severe blunt head injury
• 3 main priorities:
– Resuscitation
• Ensure adequate cerebral oxygenation
– Prevent herniation
– Rapid diagnosis of brain lesion
Airway
Modified jaw thrust
Images  Kathy Mak
Resuscitation
Breathing
– Priority is oxygenation and carbon
dioxide removal
• High flow oxygen
• Bag mask ventilation
– Although most comatose patients
require intubation, this should be
carried out by experienced
practitioners
Resuscitation
• Circulation
– Aim for MAP > 80-90 mm Hg in an
attempt to maintain adequate cerebral
perfusion pressure
– Shock is rarely a direct result of a head
injury
Following resuscitation
• BP 140/80
• SpO2 100%
• pH 7.4
• PaCO2 4.5 kPa (34 mmHg)
• PaO2 30 kPa (225 mmHg)
Image  Kathy Mak
• GCS 6 prior to sedation
and paralysis for
intubation and was
moving all limbs
What next?
–
–
–
–
CT brain?
Mannitol?
Hyperventilation?
Continue sedation &
paralysis?
Image  Kathy Mak
Treatment of ICP
• Mannitol
– Should not be given prior to evacuation of
haematoma unless there are signs of
deterioration unrelated to systemic
deterioration
– Only give after volume resuscitation
• Hyperventilation
– Hyperventilation to PaCO2 <35 mmHg should
not be carried out routinely
Sedation &
neuromuscular blockade
• Sedation reduces cerebral oxygen
demand
• Neuromuscular blockade prevents
coughing (coughing  ICP)
• Interfere with neurological examination
• agent
– no evidence regarding superiority of any
particular sedative
– use short acting agents
What now?
Image  Kathy Mak
Volume of space occupying lesion
Haematoma
Brain
tissue
Cerebrospinal
fluid
Circulating
blood
Treatment of herniation
• Mannitol
• Hyperventilation
What next?
On admision to ICU
• Haematoma evacuated
• Pupils equal, reactive
• MAP 80
• ICP 26
What next?
Image  Kathy Mak
Management
• Ensure adequate cerebral oxygen
delivery
– Oxygen saturation
– Cerebral blood flow
• Determined by cerebral perfusion pressure
CPP=MAP-ICP
– Reduce cerebral oxygen demand
• Prevent herniation
Management
• Intracranial pressure
– Treatment threshold 20-25 mmHg
• Cerebral perfusion pressure
– Target >60 mmHg
Reduce ICP
• Drain CSF
• Osmotherapy
• PaCO2 ~35 mmHg
• Improve venous drainage
– Nurse head up (30°)
– Position head and neck to ensure
venous drainage is not obstructed
Image  Kathy Mak
Decrease cerebral oxygen
demand
• Analgesia and
sedation
• Control temperature
(and treat cause of
pyrexia)
• Prevent/treat fits
Image  Kathy Mak
Other treatment
• stress ulcer &
mechanical DVT
prophylaxis
• physiotherapy
• look for and treat
coagulopathy
– not uncommon
• prevent hyperglycaemia
Image  Kathy Mak
Head injury
• Any questions?
Status epilepticus
Status epilepticus
Treat hypoglycaemia, take blood,
give O2, left lateral position
Aborted?
Yes
30 minutes
Lorazepam 0.1 mg/kg
Aborted?
Yes
Phenytoin if not
already given
Aborted?
Treat as
refractory SE
Yes
Look for cause
Regular
anticonvulsant
Status epilepticus
Treat hypoglycaemia, take blood,
give O2, left lateral position
Aborted?
Yes
Lorazepam 0.1 mg/kg
Aborted?
Yes
Look for cause
Regular
anticonvulsant
Status epilepticus
Treat hypoglycaemia, take blood,
give O2, left lateral position
Aborted?
Diazepam 0.2 mg/kg
Phenytoin 15-20 mg/kg
Yes
Lorazepam 0.1 mg/kg
Aborted?
Yes
Look for cause
Regular
anticonvulsant
Status epilepticus
Treat hypoglycaemia, take blood,
give O2, left lateral position
Aborted?
Diazepam 0.2 mg/kg
Phenytoin 15-20 mg/kg
Yes
Lorazepam 0.1 mg/kg
Aborted?
Yes
Phenytoin if not
already given
Aborted?
Treat as
refractory SE
Yes
Look for cause
Regular
anticonvulsant
Refractory status
epilepticus
• Rapid sequence induction
– Thiopentone/propofol
– Suxamethonium/rocuronium
• (NB risk of K due to
rhabdomyolysis)
• Intubate and ventilate
Image  Janet Fong
Refractory SE
• Treatment options
– Midazolam
– Propofol
– Thiopentone
• Target
– Abolition of clinical and electrical
seizure activity
Midazolam
• Dose
– 0.2 mg/kg loading
– 0.1-0.2 mg/kg/h
• Tachyphylaxis
– Requires significant dose increase after
24-48 h to maintain seizure control
Propofol
• Dose
– Loading dose 3-5 mg/kg
– Infusion 30-100 µg/kg/min
• Propofol infusion syndrome
– Severe metabolic acidosis
– Rhabdomyolysis
– Cardiovascular collapse
Key points
• Head injury
– Resuscitate first
– Maintain CPP >60 mmHg
– Reduce ICP with evacuation of SOL,
drainage of CSF, mannitol and
ventilation to PaCO2 4-4.5kPa
– Sedate, nurse head up, prevent fits &
fever, prevent hyperglycaemia
Key points
• Status epilepticus
–
–
–
–
–
True emergency
Treat hypoglycaemia
Lorazepam 0.1 mg/kg
Sedate, intubate and ventilate
Thiopentone/propofol/midazolam
infusion
Any questions?