sleep Flashcards
what is non REM sleep?
more at start of the night
synchronised, rhythmic EEG activity
partial relaxation of the muscles
reduced cerebral blood flow
reduced HR, BP + tidal volumes
some narrative images
REM sleep
most at emd of night
EEG - fast activity, fMRI - fast brain activity
similar to wakefulness
atonic muscles - except diaphragm + extraocular muscles
cerebral blood flow increases, impaired thermal regulation
narrative dreaming
when is REM sleep mainly important?
early brain development - replaces wakefulness
how long is normal circadian rhythm?
25hrs
what are parasomnias?
undesirable disorders of behaviour or experience that occur during sleep or its stages, or during sleep-wake transitions
presentation of non-REM parasomnias
non-dreaming:
- confusion arousals
- sleep walking
- sleep terrors
- paralysis
-> kids or stressed adults
presentation of REM parasomnias
enactment of the experience of dreams during REM sleep
- kicking
- punching
- talking
- sitting up
-> men in 60s/70s, assoc with neurodegenerative disorders
management of non-REM parasomnias
reassurance
- kids usually grow out of it before adolescence
management of REM parasomnias
depends on underlying cause
- if no cause symptoms are responsive to meds
narcolepsy
chronic neurological condition producing disruption to normal sleep pattern, which produces excessive sleepiness
may occur with or without cataplexy
cataplexy
sudden loss of muscle tone + power in response to strong emotion
** it always and ONLY occurs as part of narcolepsy
typical age of onset of narcolepsy
adolescence
pathophysio of narcolepsy
caused by abnormalities of the brain neurotransmitter hypocretin (orexin)
–> which is a regulator of sleep
clinical presentation of narcolepsy
daytime sleepiness
- involuntary sleep during eating/talking
cataplexy - loss of muscle tone, triggered by emotion
hypanagogic hallucinations - hallucinations occuring at sleep onset
sleep paralysis - unable to move upon falling asleep or awakening with retained consciousness
REM sleep behaviour disorder
investigations of narcolepsy
overnight polysomnography
multiple sleep latency test
management of narcolepsy
stop driving + inform DVLA
strategic daytime naps, regular exercise, education
drugs:
- daytime sleepiness - modafinil dexamfetamine, methylphenidate
- cataplexy - tricyclic antidepressants (clomipramine) or SSRIs
insomnia
unsatisfactory sleep, either in terms of sleep onset, sleep maintenance or early waking
usually secondary to stress, substance misuse
-> can become habit, anticipates insomnia
initial insomnia? common in which group?
initial insomnia = trouble going off to sleep
mania
anxiety
depressive disorders
substance misuse
middle insomnia? common in which group?
waking up in the middle of the night
sleep apnoea
prostatism
late insomnia? common in which group?
early morning wakening
depressive illness
malnutrition - anorexia
management of insomnia
hypnotic drugs - 2 weeks max, lowest dose, avoid in elderly
manage underlying cause
30% improve with advice alone - limit caffiene, avoid napping, looking at screens