Sleep, Coma, and Cognition

Question 1

Describe consciousness

Answer 1

-Assessed by behaviour (continuum= inter-observer variability)
=Alert
=Drowsy/ asleep
=Stupor
=Coma

Question 2

Stimuli used to elicit responses

Answer 2

-Verbal
-Pain
=Supra-orbital pressure
=Knuckles on sternum
=Pinch nailbed
=Pinch Achilles tendon

Question 3

GCS eyes

Answer 3

4= spontaneous
3= to command
2= to pain
1= nil

Question 4

GCS verbal response

Answer 4

5= orientated
4= confused
3= words
2= sounds
1= none

Question 5

GCS motor response

Answer 5

6= obeys commands
5= localises pain
4= flexion/ withdrawal
3= abnormal flexion
2= extends to pain
1= none

Question 6

What is a coma defined in GCS?

Answer 6

-GCS 8 or below (E2M4V2)
=E: not opening spontaneously/ to command
=V: no speech/words
=M: no movements spontaneously/ to command

Question 7

Definition of a coma

Answer 7

-Deep sustained unconsciousness
-Resulting from dysfunction of RAS and/or cerebral hemispheres
-Duration > 1 hr
=(to distinguish from other conditions)

Question 8

Causes of coma

Answer 8

-Brainstem dysfunction
=Anything directly affecting brainstem
=Cerebral hemisphere lesion causing secondary brainstem compression (coning)

-Diffuse bilateral hemisphere dysfunction

Question 9

Examples of causes of coma

Answer 9

-TRAUMA
-INFECTION
-TUMOUR
-INFARCTION/HAEMORRHAGE
-EPILEPTIC SEIZURES
-TOXIC
-METABOLIC
-HYPOXIC

Question 10

Clinical assessment of coma

Answer 10

-Critical causes: oxygen, glucose and circulation
-GCS
-Brainstem reflexes
=pupillary responses to light
=eye movements (including oculo-cephalic reflexes)
=corneal reflex
=gag reflex

Question 11

What is a vegetative state?

Answer 11

-Akinetic mutism/ apallic syndrome/ coma vigile
-Centring around idea of arousal without awareness/ brainstem function but not cortical function

-No speech
-Lies inert: no voluntary movement
-No meaningful response
-Appears intermittently alert (sleep/ wake cycle)

-Persistent state of severely altered consciousness
-Typically, severely frontal lobe/ diffuse brain dysfunction

Question 12

Cognitive domains

Answer 12

-Language (expression, reception/understanding)
-Learning and memory (verbal, non-verbal, episodic, semantic, procedural)
-Perceptual-motor function
-Complex attention
-Executive function
-Social cognition

Question 13

Examples of acquired cognitive disorders

Answer 13

-Specific cognitive deficits
-Confusion/ delirium
-Dementia/ major cognitive disorder

Question 14

Clinical neuroscience definition of dementia

Answer 14

-Acquired
-Impairment in 2 or more domains
-In a setting of clear consciousness
-Syndrome, not a disease
-Disability (not just functional impairment)

Question 15

What is assessed for cognition in a clinical setting?

Answer 15

-2 initial broad assessments

-Consciousness

-Attention, concentration, orientation

Question 16

What is asked in a history assessing cognition?

Answer 16

-Patient/ Relatives, friends, colleagues/ Nursing staff
-Speech vs language (reception and expression, reading and writing)
-Disturbed attention
=putting things in wrong place
=what did I come in here for?

Question 17

Three general steps in syndromic diagnosis and aetiological diagnosis

Answer 17

-Is there a major cognitive disorder?
=Acquired, in clear consciousness, 2 or more domains affected, disability

-What is the cognitive profile?
=Which domains affected

-What is the underlying cause?
=Cognitive profile, time course, age
=Any other neurological features
=Any specific PH, PMH, FH

Question 18

Investigations in cognitive assessment

Answer 18

-Routine blood tests (renal-hepatic, hypothyroid, vitamin deficiency)
-Brain imaging
-Depends on context
=Detailed neuropsychology assessment
=Genetic tests, autoimmune, specific infections, malignancy (paraneoplastic syndromes)

Question 19

Classification of sleep disorders

Answer 19

-Insomnias
-Sleep-related breathing disorders (drowsiness in day)
-Non-respiratory related hypersomnia (narcolepsy)
-Circadian rhythm disorders (timing of sleep)
-Parasomnias (experiences/ behaviours in and around sleep)
-Sleep-related movements

Question 20

Elements of the sleeping history

Answer 20

-Establish main complaint

-What happens in sleep/ wakefulness/ transitions (typical 24hr profile)

=Time to bed/ sleep/ waking/ rising
=Sleep rituals and maintenance
=Events in sleep (including dreaming)
=Feelings on waking
=Additional drowsiness/ sleep at other times

=Snoring (apnoea)
=Drug history
=History related to other relevant factors (stress)

Question 21

The Epworth sleepiness scale

Answer 21

-Sleep during the day
0-3 likelihood in 8 situations
>10/24 significant EDD (excessive daytime drowsiness)

Question 22

Two sleeping histories needed

Answer 22

-Past personal sleep history
=eye-witness account?
-Family sleep history (genetic elements)

Question 23

Timing in sleep disorders

Answer 23

-NREM (1 hour after sleep)
-REM (corresponding)
-Sleep onset/offset problems

Question 24

Parasomnias

Answer 24

-NREM:
=Night terrors
=confusional arousals
=sleep walking

-REM:
=REM sleep behaviour disorder (Parkinsons)
=Sleep paralysis
=nightmare disorder

Question 25

Sleep-related movement disorders

Answer 25

-Restless legs syndrome
-Periodic limb movements
-Hypnic jerks
-Some forms of epilepsy specifically related to sleep