Sleep Flashcards
sleep
rapidly reversible state of reduced responsiveness, motor activity, and metabolism
polysomnogram
primary tool for assessing sleep for clinical and research purposes using 30 second epochs of EEG, EMG, and EOG
sleep architecture
*sleep stages occur in cycles lasting 90-120 minutes each
*4 to 5 cycles occur during a typical night of sleep
*typically, increased percentage of NREM in the first half of the night and increased percentage of REM in the second half
wakefulness on polysomnogram
*EEG 8-13 Hz (alpha)
*variable muscle movements
*eye movements present
stage N1 sleep
*transitional or light sleep (drowziness)
*at least 50% of epoch has low amplitude mixed theta (4-7 Hz)
*slow rolling eye movements
*little muscle
*VERTEX WAVES late in N1
stage N2 sleep
*largest proportion of sleep time in normal adults (40-55% of night); when teeth grinding occurs
*theta frequency dominates
*SLEEP SPINDLES 11-16 Hz, central, brief
*K complexes (negative sharp followed by a positive, last > 0.5 sec
what stage of sleep is characterized by sleep spindles
stage N2 sleep
stage N3 sleep
*deep or slow wave sleep
*about 10-20% of sleep
*sleepwalking, night terrors, and enuresis occur during this stage
*at least 20% of epoch is 0.5-2 Hz high amplitude delta
*occurs more in first half of night
REM (stage R) sleep - polysomnograph
*EEG is low voltage, mixed with sawtooth 2-6 Hz brief bursts
*EOG with conjugate irregular, sharply peaked eye movements initial phase < 500 msec
*ATONIA on EMG (inhibition of alpha motor neurons)
which stage of sleep is characterized by atonia
REM sleep
REM sleep characteristics
*characterized by atonia and rapid eye movements
*less than 25% of sleep time, onset after 90 minutes, duration increases later in night
*typically associated with vivid dreams/nightmares
*increased brain O2, erections, variable and increased pulse and BP, may serve memory processing functions
phasic and tonic REM
-phasic REM: bursts of rapid eye movements, respiratory variability, and brief EMG (twitches)
-tonic REM: fewer eye movements, more limited motor activity
arousals (during sleep)
*abrupt shift of EEG frequency that lasts at least 3 seconds with 10 seconds of stable sleep preceding the change
*waking up transiently then returning back to the stage of sleep they were in
*if during REM, requires a concurrent increase in EMG for at least 1 second
medications that suppress REM
*sedative-hypnotic
*barbiturates
*antiepileptic drugs
*beta blockers
*MAOI
*SSRIs
*stimulants
*tricyclic antidepressants
*EtOH
medications that enhance REM when you withdraw from them
*EtOH
*BDZ
*TCA
*MAOI
short term insomnia
*sx < 3 months
*often temporally related to a stressor
chronic insomnia
*sx at least 3x per week over 3 or more months
recommendations for treating chronic insomnia
sleep hygiene, stimulus control, include relaxation, sleep restriction therapy, cognitive therapy, and cognitive behavioral therapy for insomnia (CBT-I)
central sleep apnea
*repetitive cessation or decrease of BOTH airflow and ventilatory effort during sleep
*typically present with symptoms of disrupted sleep, such as excessive daytime sleepiness, poor subjective sleep quality, insomnia, inattention, and poor concentration
*tx with nocturnal O2 (CPAP), adaptive seroventilation
obstructive sleep apnea (OSA)
*obstructive apneas, hypopneas, or respiratory effort related arousals
*5+ obstructive respiratory events (microarousals) per hour (with accompanying medical risks) or 15 such events without any other factors
*daytime symptoms attributable to disturbed sleep, such as sleepiness, fatigue, headaches, or poor concentration
*signs of disturbed sleep, such as snoring, restlessness, or resuscitative snorts
obstructive sleep apnea - management
*weight reduction
*positive airway pressure (CPAP)
*orthodontic devices
*ENT surgery
*hypoglossal nerve stimulation (Inspire)
narcolepsy type 1
*narcolepsy with cataplexy
*decreased orexin (hypocretin) in lateral hypothalamus
*transient facial weakness or falls triggered by joking or laughter, or the inability to move for 1-2 minutes immediately after awakening or just before falling asleep
*begins in teens to early 20s
narcolepsy type II
*narcolepsy (falling asleep abruptly) without cataplexy
+/- decreased orexin
narcolepsy evaluation
1) multiple sleep latency tests (MSLT) - 4-5 repeated naps which are terminated at up to 20 minutes to document sleep latencies
*mean sleep latency < 8 minutes
*typically shows REM sleep within 15 minutes of onset of sleep (abnormal)
excessive daytime somnolence
*the inability to maintain wakefulness and alertness during the major waking episodes of the day with sleep occurring unintentionally or at inappropriate times almost daily for at least 3 months
treatments for excessive daytime somnolence
modafinil, armodofinil, and sodium oxybate
Epworth Sleepiness Scale (ESS)
*one page questionnaire that estimates likelihood of dozing off in 8 typical sedentary situations
scores:
1-6 : normal sleep
7-8: average sleepiness
9-24: abnormal (pathologic) sleepiness
parasomnias
*undesirable physical events (movements, behaviors) or experiences (emotions, perceptions, dreams) that occur during entry into sleep, within sleep, or during arousals from sleep
NREM parasomnias
characterized by recurrent episodes of incomplete awakening, with absent or inappropriate responsiveness, limited cognition, and partial or complete amnesia of the event
*confusional arousals
*sleepwalking
*sleep terrors
*sleep-related eating disorders
REM-related parasomnias
*sleep paralysis (inability to move for 1-2 minutes after awakening)
*nightmare disorder
*REM behavior disorder
REM behavior disorder
*a type of REM-related parasomnia
*presence of REM sleep without atonia on polysomnography
*repeated episodes of sleep-related vocalization and/or complex motor behaviors
treating REM behavior disorder
*avoid medications that exacerbate RBD (SSRIs and tricyclic antidepressants)
*ensure safe sleeping environment (remove weapons, provide bed alarm, sleep alone)
*melatonin in high doses at bedtimes
restless leg syndrome (Willis-Ekbom)
*an urge to move the legs when sitting still/about to go to sleep
*usually accompanied or caused by uncomfortable or unpleasant sensations in the legs, worsening during periods of rest or inactivity, partially relieved by movement
*reduced CNS iron is a consistent finding
periodic limb movement syndrome
*periodic episodes of repetitive and highly stereotyped limb movements that occur during sleep
*can occur simultaneously in both legs, alternate, or occur unilaterally
*seen in > 80% of patients with restless leg syndrome
