Flashcards in Sleep Phys Deck (21):
Sleep is a behavioral state:
Individual need genetically determined
Compensation following sleep loss i.e. sleep more after sleeping less = homeostatic drive likely due to adenosine buildup.
Why do we sleep?
brain and body regeneration (NREM sleep, N3 SWS) and brain development/memory **** (REM sleep).
Performance of learned motor tasks improve after sleep, but not after similar period of wakefulness
Improved performance correlates with increases in focal delta over involved cortex during sleep
REM sleep essential for the developing mammalian brain, but functions of REM sleep in adults uncertain
Stage 3-4 (delta), now N3 sleep may be involved in synaptic “pruning” and “tuning
We likely evolved to take advantage of:
morning blue-green light; the orange – red spectrum of late afternoon and evening does not have the same salutary effects
NREM (N1, N2, N3 [SWS] sleep)
high amplitude slow brain waves, increased arousal threshold compared to wake, decreased muscle activity, slow rolling eye-movements, decreased heart rate, respirations and metabolism.
rapid-eye movement sleep (REM) – every ~90 minutes
in adults - EEG looks awake but arousal threshold is higher than in SWS= an active brain in a paralyzed body. Eyes move, muscles paralyzed, except for eyes & diaphragm, temperature regulation suspended (like reptiles), brain temperature rises, engorgement of clitoris and penis; heart and respirations become irregular. When awakened, 85% report dreams though dreams also reported at a lower frequency in SWS
(walking, terrors, confusional arousal, and night eating syndrome) usually arise early out of N3, SWS.
Disorders of arousal
usually arises later, out of REM sleep
REM sleep behavior disorder
~90 minutes. Short REM latency seen in depression, alcohol withdrawal, very short seen in narcolepsy.
Normal latency to REM
Insufficient sleep opportunity – Poor sleep habits
Circadian rhythm disorders e.g. delayed sleep phase, shift-work, jet lag
Obstructive or central sleep apnea (CSA may be precipitated by opioid use). 70% of OSA patients are sleepy, 30% not ****
Depression: especially seasonal, atypical, bipolar
Drug use or withdrawal
Medical illness e.g. renal or hepatic failure, brain tumors, neurodegenerative disorders
High Epworth: Excessive daytime sleepiness (EDS)
driven by cholinergic pedunculo-pontine and laterodorsal tegmental (PPT/LDT) neurons
Sleep Diagnoses through the life-cycle Kids:
Disorders of arousal: walking, night terrors, confusional arousals. Worry about safety.
Sleep Diagnoses through the life-cycle Kids and adolescents
OSA. Circadian mismatch- delayed sleep phase syndrome (night owl). Worry about school
Sleep Diagnoses through the life-cycle Adolescents & young adults:
poor sleep hygiene & sleep deprivation. Narcolepsy. Worry about driving & accidents. Sleep during pregnancy.
Sleep Diagnoses through the life-cycle On-call:
Deprivation and circadian mismatch- shift-work sleep disorder.
Sleep Diagnoses through the life-cycle Older:
learned or “conditioned” insomnia, obstructive sleep apnea, restless legs syndrome & periodic limb movement disorder (all can be in kids, too). Safety?
Sleep Diagnoses through the life-cycle 50+
REM Sleep Behavior Disorder. Again, safety?
Anxiety and depression
Conditioned / learned insomnia
Low Epworth: Fatigue
waking discomfort. Urge to move legs and/or arms, with onset or worsened by rest, usually at night, and somewhat relieved by movement. ? Associated with HTN
Potentially “iatrogenic” along with REM sleep behavior disorder, sleep walking and OSA - precipitated or worsened by psychotropic medications.
Get serum ferritin and undergo fe replacement if 55 or less (will be reported as “normal”)
Fe = cofactor in dopamine metabolism
Restless Legs Syndrome insomnia or EDS or both
Both can be precipitated by psychotropic medications Both have been associated with serious injury to the patient and to those patients may encounter.
Walking & REM Sleep Behavior disorder
genetic propensity, usually in children, out of slow wave sleep usually in first part of sleep period, partially or totally amnestic for event. Look for causes of increased sleep pressure and sleep disruption e.g. sleep schedule, deprivation, medications, drugs, obstructive sleep apnea, RLS, etc.
Disorders of Arousal (sleep walking, night terrors):