Lecture 50: Sleep Flashcards
Stage 1 Sleep EEG and corresponding body state
Light sleep, less alpha, theta waves; muscle activity slows, twitching
Stage 2 Sleep EEG and corresponding body state
Theta waves, sleep spindles, K complexes; slowed breathing, HR
Stage 3 & 4 Sleep EEG and corresponding body state
Delta waves; very limited muscle activity
What stage is the most common? %
Stage 2; about 50%
Restorative sleep is which stage?
Stages 3 & 4
REM Sleep EEG and corresponding body state
Similar to waking state; paralysis, rapid eye movements, dreaming, increased HR, rapid breathing
How much time a night do we spend in REM? (% and # cycles)
25%, 5 cycles
Sleep cycle. How long does the pattern take?
Awake –> stage 1 –> 2 –> 3 –> 4 –> 3 –> 2 –> REM (like stage 1) –> 2; repeats every 90-120 minutes
Sleep latency
Time from lights out to stage 1 (10-20 min)
REM latency
Time from sleep onset to first REM (90-100 min)
Sleep efficiency
Amount of sleep/total time in bed
For infants, how much time do you spend sleeping?
2/3 of the day
As we age, what happens to our sleep cycle?
Increased sleep latency, noctural awakenings and stage 1, decreased REM latency, sleep efficiency, and stage 4
What are some key pieces of information for a patient with disordered sleep?
Sleep hx, meds, family/psych hx, bed partner hx, physical exam, sleep measurements
Scale for measuring sleepiness and structure
Epworth Sleepiness Scale asks likelihood to fall asleep in various situations
What does the multiple sleep latency test assess?
Objective daytime sleepiness: sleep/REM latency during day
What suggests narcolepsy
REM sleep in 2+ naps
Primary sleep disorders (2)
Dyssomnias = too much or too little sleep; Parasomnias = abnormal sleep behaviors
Sleep-related breathing disorders are categorized as…
A dyssomnia
Define sleep apnea
Repetitive episodes of complete or partial cessation of air flow during sleep that often result in oxygen desaturation and terminate with brief arousals
Two types of sleep apnea
Central = reduction in respiratory drive; Obstructive = upper airway obstruction
Two causes of obstructive sleep apnea
Obesity or craniofacial abnormalities (leading to soft tissue collapse of airway)
Signs of obstructive sleep apnea (3)
Excessive daytime sleepiness, loud/choking snoring, pauses in breathing while sleep
Consequences of sleep apnea on all causes of mortality
3-6 x fold in all-causes of mortality
Cardio consequences of sleep apnea
CHF, stroke, hypertension
Neurocognitive consequences of sleep apnea
Accidents, decreased vigilance, executive functioning
Metabolic consequences of sleep apnea
Increased insulin resistance
Prevalence of sleep apnea (%)
15%
Main sleep apnea treatments (3)
Weight loss, positional therapy, C-pap (positive airway pressure therapy)
Central sleep apnea means what? What people get it?
No respiratory effort at time of airflow cessation; patients w/ lower brainstem lesions
Clinical feature of narcolepsy
Frequent attacks of irresistible daytime sleepiness; REM sleep INTRUDING when it’s not supposed to
What is the “classic tetrad” of narcolepsy
“Classic Tetrad” = daytime sleepiness, cataplexy, sleep paralysis, hypnagogic hallucinations
T/F: Narcoleptics get normal amounts of sleep per 24 hours
True! Also have normal polysomnogram
Hypnagogic hallucinations (def)
Vivid hallucinations during transition between wakefulness and sleep
Cataplexy (def)
Sudden intrusion of REM sleep into wakefulness resulting in emotionally-triggered, transient muscle weakness
Narcolepsy can involve what hormone?
Orexin (reduced or absent)
Narcolepsy diagnosis involves…
Clinical assessment, REM latency via polysomnography
Pharmacologic narcolepsy treatments (2 categories)
Stimulants and cataplexy modifying agents (sodium oxybate, REM-suppressing antidepressants)
Board sleep disorders (2)
Ondine’s curse (sleep –> stop in breathing); Kleine-Levin syndrome (daytime somnolence and other hypers-)
Circadian rhythm disorders (def)
Recurrent or persistent misalignment between the desired sleep-wake schedule (external physical or social environment) and the endogenous circadian rhythm-related propensity for sleeping and waking
Circadian rhythm disorders are often associated with…
Night & early-morning shift schedules
Shift work sleep disorder (def)
Excessive sleepiness during work hours that are scheduled during the usual sleep period and insomnia when attempting to sleep during the usual wake period
Sleep-related movement disorders include which two disorders with brief description
Restless leg syndrome (urge to move legs) and periodic limb movements of sleep (partner notes this one)
RLS and PLMS are primarily; most important secondary cause? One associated disease
Idiopathic; iron deficiency; Parkinson’s disease
Non-REM Parasomnias (2) and stage. Amnesia? Confusion? Dreaming? Patients?
Sleepwalking and sleep terror disorder; delta sleep (Stage 3 & 4); yes, yes, no, children
REM Sleep Parasomnias (2) and stage. Amnesia? Confusion? Dreaming? Patients?
Nightmare disorder, REM behavior disorder (REM); no, no, yes, older men
Pathophysiology of non-REM parasomnia
Brief, incomplete awakening during Stage 3 & 4 sleep
What’s behind/presentation of sleep terror
Waking from Stage 3 & 4 with gasping, panic, and then return to sleep w/out fully waking
Pathophysiology of REM behavior disorder and important association
Loss of muscle atonia during REM sleep resulting in acting-out of dreams; early manifestations of neurodegenerative disorders
