Neuro Capsules

Question 1

What is the monro-kellie doctrine?

Answer 1

The idea that the cranium is made from brain, blood and CSF

Question 2

What is the name and optimum pressure that allows oxygen and glucose to leave blood into the brain? Why does brain injury affect this?

Answer 2

Cerebral perfusion pressure = 60-70mmHg

Requires low ICP

MAP-ICP= perfusion pressure (CPP)

Question 3

Ideal ICP

Answer 3

ICP should be less than 10mmHg

Question 4

On a CT, what does white mean?

Answer 4

White = calcium or blood

Bifrontal contusions

Question 5

What do you do if someone has dropped their GCS to less than 8? A-J

Answer 5

A - if GCS <8, call ICU or anaesthetist

B - think pCO2 as well as O2

C - circulation - think brain perfusion and metabolism

D - GCS, pupils, focal neurology, seizures
E - Blood sugar, temperature
F - fluids - HYPERtonic saline if raised ICP, or normal saline if normal
G and H - Get Help!!
I - imaging, urgent CT head
J - jerking - need for anti-epileptics (nystagmus of pupils in those who are paralysed)

Question 6

What happens to the blood flow as carbon dioxide levels?

Answer 6

As it increases, the blood flow to the brain increases, which actually worsens the ICP

Question 7

Where do you measure the mean arterial pressure?

Answer 7

Measure using arterial line - put the transducer at the level of the brain, at the level of the tragus of the ear

Question 8

Difference between systolic in heart and brain

Answer 8

Systolic - 10 = brain systolic

Question 9

Which can you not give hypotonic fluids like dextrose for neurosurgery patients?

Answer 9

If the fluid is hypotonic in comparison to the blood, it causes the fluid to seep into third spaces, causing oedema.

Question 10

Mannitol

Answer 10

Diuretic

Question 11

Pupils

Answer 11

Document size, shape and reaction to light

Question 12

If the patient is fully awake but there is no reaction to light, what do you do? What might you need to consider?

Answer 12

Check accomodation

Consider correlation to GCS
Direct injury to globe 
Previous eye surgery or cataracts 
Opthalmoscopy
CN3 palsy

Question 13

Which palsy gives you a dilated pupil?

Answer 13

CN3

Question 14

If someone is not obeying commands, what do you think about?

Answer 14

Is there spontaneous movement

Are these purposeful e.g. trying to pull out NG tubes - means there is higher cortical involvement

Question 15

What things might cause false neurological signs?

Answer 15

CN 7 palsy

Kernohan’s notch -

Question 16

What do you call paralysis after epilepsy?

Answer 16

Todd’s paresis - post ictal

Question 17

What is Kernohan’s notch?

Answer 17

A MASSIVE subdural haematoma crushes contralateral brainstem, causing IPSILATERAL weakness to the haematoma

Question 18

What do you do if someone has hydrocephalus? How do you avoid coning?

Answer 18

External ventricular drain - if you set it at a particular level, the CSF will only come out if it is at that level or higher. The EVD is from the skull so avoids coning.

Question 19

What do you call a catheter in the brain?

Answer 19

Shunt - CSF form ventricle gets siphoned into peritoneum.

Question 20

What do you do if someone has a shunt but the patient has low GCS suddenly? What investigations do you do?

Answer 20

If the valve setting is incorrect, if the shunt isn’t working properly

Shunt series x ray of head neck and abdomen

Question 21

Why might someone have a shunt?

Answer 21

Intraventricular haemorrhage

Question 22

What is status epilepticus?

Answer 22

Recurrent seizures over 1 hr with breaks, but never quite recover
OR
epilepsy for 5 minutes or more

Question 23

What is Keppra?

Answer 23

Levetiracetam

Question 24

If someone’s pregnant, which antiepileptic do you give?

Answer 24

Lamotrigine

Question 25

Management for status epilepticus

Answer 25

See if it stops spontaneously after 5 minutes
IF not, give IV lorazepam

then phenytoin or levetiracetam

Question 26

Why would you choose levetiracetam over phenytoin?

Answer 26

Pheny - cardiac SE and requires central line to administer therefore pt needs to be on cardiac monitor. Complicated.

Leve can be given peripherally through a venflon therefore easier.

Question 27

Treatment for focal epilepsy

Answer 27

CBZ

le

Question 28

Treatment for generalised epilepsy

Answer 28

Sodium val

CBZ

Question 29

Post-op urinary retention - what do you do?

Answer 29

Take pt to toilet and turn tap on

Insert catheter

Question 30

Types or urinary retention and causes

Answer 30

Painful urinary retention - due to bladder, prostate etc

Painless retention - neurogenic e.g. due to cauda equina syndrome or nerve problems

Question 31

Post op urinary retention 3 days after neurofibroma spine surgery - what do you do? Why has this occured?

Answer 31

Insert catheter
Document residual volume

Full neurological examination
MRI scan
Escalate to seniors

The three days have allowed something to expand (haematoma, black on MRI due to haemosiderin)

Question 32

FEATURES OF NEUROGENIC SHOCK

Answer 32

Spinal injury above T1, therefore no sympathetic chain, therefore autonomic dysfunction:

Bradycardia
Hypotension
Poikilothermia

Noradrenaline

Question 33

Neurogenic vs spinal shock

Autonomic dysreflexia

Answer 33

Injury to spine T6 or below means you’ve lost your PNS but sympatheic chain intact means:

Any small stimulus will lead to uninhabited sympathetic activity - tachycardic, tachypnoea, sweating, distended neck veins

Question 34

Neurogenic vs spinal shock

Autonomic dysreflexia

Answer 34

Injury to spine T6 or below means you’ve lost your PNS but sympathetic chain intact means:

Any small stimulus will lead to uninhabited sympathetic activity - tachycardic, tachypnoea, sweating, distended neck veins