Sleep Disorders

Question 1

stage 1

Answer 1

drowsiness and early eeg slowing

Question 2

stage 2

Answer 2

asleep but easily aroused

Question 3

Stage 3 and 4

Answer 3

sleep deepens, harder to arouse, slower delta wave eeg recorded

Question 4

when does first REM period occur

Answer 4

about 90 mins after sleep begins, reoccurs every 90 mins thereafter lengthening in time from a few mins to an hour

Question 5

when is limb hypotonia maximal?

Answer 5

in REM sleep

Question 6

eeg recording during REM sleep

Answer 6

similar to that of wake state, recallable dreams occur, important for reinforcing memory traces

Question 7

ARAS (ascending reticular activating system)

Answer 7

• important for arousal and wakefulness
• arises from rostral pons, caudal midbrain, posterior hypothalamus, and basal forebrain to activate cerebral cortex directly or via thalamus

Question 8

what does ARAS suppress

Answer 8

ventrolateral preoptic area of the hypothalamus

Question 9

what does an ARAS lesion (aka ischemic infarct of upper brain stem) cause

Answer 9

persistent somnolence or coma

Question 10

pontine REM center

Answer 10

activates the brain stem gaze centers responsible for typical REM eye movements and induces hypotonia and inc autonomic activity by descending reticulospinal pathways

Question 11

What area promotes REM and NREM sleep

Answer 11

preoptic area of the ventrolateral hypothalamus which receives input from suprachiasmatic nucleus and has receptors for sleep-inducing peptides and cytokines

Question 12

sleep apnea

Answer 12

• daytime sleepiness

- frequent episodes–>nocturnal hypoxemia–>pulm HTN or cardiac arrhythmias

Question 13

obstructive sleep apnea

Answer 13

• 2/2 upper AW obstruction despite contraction of diaphragm and chest wall muscles
• typically obese

Question 14

how is OSA diagnosis made

Answer 14

• overnight sleep study
• EEG, EKG
• oximetry
• respiratory and videotape monitoring

Question 15

OSA tx

Answer 15

• weight loss
• uvulopalatopharyngoplasty
• mask devices delivering pressurized oxygen d/r sleep

Question 16

central sleep apnea

Answer 16

• occurs in absence of any diaphragmatic or respiratory effort to breathe
• may need mech ventilation while they sleep

Question 17

define narcolepsy

Answer 17

• REM sleep at inappropriate times

- hypocretin (orexin) deficiency

Question 18

classic features of narcolepsy

Answer 18

• narcoleptic attacks
• cataplexy
• sleep paralysis
• visual hallucinations when falling asleep/waking up

Question 19

narcoleptic attacks

Answer 19

-abrupt, multiple, intrusions of sleep during daytime activities

Question 20

define cataplexy

Answer 20

• periodic loss of muscle tone provoked by emotional triggers
• slump to ground b/c of REM limb hypotonia; stays awake, recalls event

Question 21

sleep paralysis

Answer 21

-occurs when REM hypotonia transiently prevents pt from getting out of bed on awakening

Question 22

REM and narcolepsy

Answer 22

-recallable dreams of REM=basis for vivid hallucinations experienced by narcolepsy pts when falling asleep (hypnagogic hallucinations) or waking up (hypnopompic hallucinations)

Question 23

how is narcolepsy diagnosis made

Answer 23

-multiple sleep latency tests where abnormally early onset of REM is recorded

Question 24

medications to enhance wakefullness in narcoleptic pts

Answer 24

• Methylphenidate (amphetamine-like stimulants)
• Modafinil (stimulants unrelated to amphetamine)
• —Mo can also treat daytime somnolence from sleep apnea

Question 25

what is helpful in reducing cataplexy

Answer 25

-drugs with REM suppressing properties like TCAs

Question 26

insomnia

Answer 26

-hypnotics are helpful for short-term insomnia

Question 27

somnambulism (sleep walking)

Answer 27

• disorder of stage 4 sleep

- sometimes assoc with bed wetting in kids

Question 28

stage 4 disorders

Answer 28

• sleep walking

- night terrors

Question 29

REM behavior disorder

Answer 29

• older male pts lack nml hypotonia of REM

- often preceds onset of Parkinson’s dz or Lewy body dementia