coma, persistent vegetative state and brain death

Question 1

Define coma

Answer 1

A state of unrousable psychological unresponsiveness in which the subjects lie with eyes closed and show no psychologically understandable response to external stimulus or inner need

Question 2

What 2 things does consciousness rely on

Answer 2

intact ascending reticular system

Functioning cerebral cortex

Question 3

What is the ascending reticular activating system responsible for?

Answer 3

awakening and alerting element of consciousness

Question 4

What is the functioning cerebral cortex responsible for?

Answer 4

content of that consciousness - awareness

Question 5

What GCS score(s) is defined as a coma

Answer 5

less than 8

Question 6

Causes of decreased GCS

Answer 6

sepsis, hypoxia, hypotension,
drug intoxication, renal failure
hypoglycaemia
seizures, damage to reticular activating system
Raised ICP eg hydrocephalus, tumour, stroke, haemorrhage

Question 7

What is persistent vegetative state?

Answer 7

A state in which the brainstem recovers to a considerable extent but there is no evidence of recovery of cortical function

Question 8

What is the locked in syndrome?

Answer 8

The patient has total paralysis below the level of the 3rd nerve nuclei and can open, elevate and depress eyes although no horizontal eye movement and no other voluntary movement

Question 9

Give an example of when locked in syndrome could occur

Answer 9

Stroke in basilar artery denying pons of blood supply

Question 10

Breathing - what does fluctuating breathing and depressed respiration suggest?

Answer 10

fluctuating - brainstem lesion

depressed - drug overdose

Question 11

First resuscitation and investigation of patient

Answer 11

ABC

Question 12

Circulation - investigations

Answer 12

blood - glucose, biochemistry, haematology, blood gas and toxicology
blood pressure, pulse, temperature, IV access, stabilise neck
MENINGITIS

Question 13

What is always important to discount in a coma patient?

Answer 13

meningitis

Question 14

3 types of history for coma

Answer 14

expected progression eg renal failure
unpredictable with no known cause
unexpected eg head injury

Question 15

Some monitoring of the patient would include..

Answer 15

temperature 
respiratory and heart rate 
bp
abdomen 
meningism 
fundal examination

Question 16

meningism triad

Answer 16

neck stiffness
photophobia
headache

Question 17

3 neurological assessment of coma

Answer 17

GCS
brainstem function
motor function and reflexes

Question 18

How would you test brainstem function?

Answer 18

pupillary reaction, spontaneous eye movement, corneal response, occulovestibular response, respiratory pattern, dolls eye

Question 19

Testing motor function and reflexes

Answer 19

motor response
muscle tone
tendon reflexes
seizures

Question 20

GCS - 3 parts

Answer 20

eye opening
best verbal response
best motor response

Question 21

GCS - eye opening grading

Answer 21

4 = spontaneous 
3 = to voice 
2 = to painful stimuli 
1 = none

Question 22

GCS - best verbal response grading

Answer 22

5 - orientated 
4 - confused 
3 - inappropriate 
2 - incomprehensible sounds 
1 - none

Question 23

GCS - best motor response grading

Answer 23

6 = obey commands 
5 = localise to pain 
4= withdraw from pain 
3= flex
2= extend
1= none

Question 24

For each of the 3 categories what score represents a coma?

Answer 24

eyes - 2 or less
voice - 2 or less
motor - 4 or less

Question 25

Causes of coma without focal signs or meningism

Answer 25

anoxia, seizure/epilepsy, ischaemia, intoxications, metabolic disturbances, systemic infections, hyper/hypothermia

Question 26

Investigation of coma without focal signs or meningism

Answer 26

``` toxicology screen - alcohol blood sugar and electrolytes hepatic and renal function blood gas and acid base assessment blood pressure CO poisoning ```

Question 27

3 main causes of coma without focal signs but with menigism

Answer 27

subarachnoid haemorrhage meningitis encephalitis

Question 28

Investigation of coma with menigism only

Answer 28

CT head | lumbar puncture

Question 29

4 things to look for in lumbar puncture in coma with meningism

Answer 29

cell count capsular antigen test glucose level appearance

Question 30

4 main causes of coma with focal brainstem or lateralising cerebral signs

Answer 30

cerebral tumour, haemorrhage, infarction or abscess

Question 31

Investigation of coma with focal signs

Answer 31

MRI/CT | metabolic screen, lumbar puncture, EEG

Question 32

Medical causes of coma lasting more than 5 hours

Answer 32

drug/alcohol ingestion hypoxia eg MI haemorrhage eg infarction metabolic eg diabetes

Question 33

Prognostic factors in coma outcome

Answer 33

``` age cause of coma depth of coma duration of coma clinical signs ```

Question 34

Continuing care of patients in a coma includes

Answer 34

``` maintain vital functions care of skin and avoid pressure sores prophylaxis of DVT bladder and bowel control seizures and prevent contractures consider locked in syndrome ```

Question 35

Why can head injury lead to focal neurological signs?

Answer 35

diffuse axonal injury contusion - bruising intracerebral haematoma extracerebral haematoma eg extradural and subdural

Question 36

How to manage head injury

Answer 36

``` stabilise cervical spine ABC GCS - intubate and ventilate treat raised ICP cranial imaging neuro observations ```

Question 37

How to treat raised ICP

Answer 37

``` surgery to relieve pressure osmotic agent eg mannitol head at angle for venous return reduce pain maintain good PO2 and reduce PCO2 reduce metabolism eg barbiturates ```