Sleep Medicine Flashcards
True or False: Hypertension can be secondary to OSA
T
True or False: Sleep disorders are underdiagnosed
T
What special history acronym is part of sleep history?
BEARS
Bedtime
Excessive daytime sleepiness
Awakenings: night wakings
early morning waking
Regularity and duration of sleep
SnoringWhat are some questions to ask a partner of whom sleep disorder is in question?
Bed partner’s observations
Snoring
leg movements
What are some medical conditions that should be asked to a patient suspected of sleep disorder?
Asthma
Reflux
Angina
What are causes of excessive daytime somnolence?
- sleep deprivation
- fragmented sleep
- primary sleep disorder
How to diagnose a sleep disorder?
Overnight sleep study = Polysomnography
What does the polysomnography record?
Sleep stage, breathing, oxygen and heart rate +
Leg movements
ECG
Video camera
What are some etiologies of EDS?
- Drugs
Hypnotic-dependent sleep disorder
Stimulant-dependent sleep disorder
Alcohol-dependent sleep disorder
- Respiratory-Induced: Snoring Upper Airway Resistance Syndrome Obstructive sleep apnea Central sleep apnea Periodic breathing (Cheyne-Stokes)
- Periodic Leg Movements
- Narcolepsy
- Idiopathic Hypersomnolence
What are some characteristics of UARS?
Snoring, large pleural pressure swings
What is obstructive sleep apnea on polysomnograph?
A complete blockage of the airway despite efforts to breath. Notice the effort gradually increasing ending in airway opening.
What is hypopnea on polysomnograph?
This is an 18 second hypopneic event. The airflow signal is reduced by approximately 50% during this event.
What is normal snoring?
Fewer than 5 obstructions (apneas + hypopneas) per hour
T or F: OSA affects all ages
T
What are causes of sleep apnea?
Imbalance in pressures keeping airway open
Pharynx collapses with breath
Anything which narrows airway makes sleep apnea more likely.
Anything which causes loss of muscle tone increases risk of sleep apnea.
What are some anatomical causes of sleep apnea?
Abnormal anatomy of head and neck Retorgnathia Obesity Family history Ethnicity
What are the symptoms of sleep apnea?
Daytime sleepiness Waking at night choking Intellectual impairment Increased irritability Sexual impairment
What are some heart complication as a result of
Increased risk of hypertension
Increased risk of MI
Increased risk of stroke
Excess mortality is due to cardiovascular causes
What are some treatments for sleep apnea?
Nasal CPAP (the gold standard)
Dental appliance
Surgery:
UPPP
Cricoid resuspension
Mandibular advancement
What is central apnea on polysomnograph?
A complete cessation of airflow resulting from a Reduction in respiratory effort . The upper airway is patent, but the respiratory center temporarily fails to trigger.
What is mixed sleep apnea?
OSA + CSA = mixed sleep apnea
T or F: CSA is more common than /oSA
F: OSA is more common
What is the treatment for CSA?
Identify and treat reversible risk factors
BPAP with back-up rate
How to diagnose Periodic Leg Movements (PLMS)?
Diagnosed by polysomnography EMG
What is PLMS?
Repetitive, stereotypic, uncontrollable movements of lower limbs
Association with Restless Leg Syndrome
Incidence increasing with age
What confirms narcolepsy?
MSLT confirmatory:
4 of 5 naps showed sleep onset REM
Sleep latency 2-3 minutes
What are symptoms of narcolepsy?
Sleepiness
Cataplexy
Sleep paralysis
Hypnagogic hallucinations
What is cataplexy?
- Loss of muscle tone
REM intrusion
Often brought on by emotions - Severe fall to the ground
only respiratory muscles spared - More usually just momentary laps
head sags
knees buckle - Dominant inheritance with variable penetrance
Half relatives have sleepiness
What are the treatments for narcolepsy?
Stimulants:
Dextroamphetamine
Methamphetamine
Modafanil**
Tricyclic Antidepressants:
Protriptyline
Imipramine
Fluoxetine **
What is an AHI index?
The AHI is the number of apneas or hypopneas recorded during the study per hour of sleep. It is generally expressed as the number of events per hour.
What are the classes based in AHI?
None/Minimal: AHI < 5 per hour
Mild: AHI ≥ 5, but < 15 per hour
Moderate: AHI ≥ 15, but < 30 per hour
Severe: AHI ≥ 30 per hour
What is MSLT?
The multiple sleep latency test (MSLT) tests for excessive daytime sleepiness by measuring how quickly you fall asleep in a quiet environment during the day.
MSLT is used to diagnose which diseases?
MSLT is the standard tool used to diagnose narcolepsy and idiopathic hypersomnia
What are the stages in sleep an in order?
Usually sleepers pass through four stages: 1, 2, 3, and REM (rapid eye movement) sleep. These stages progress cyclically from 1 through REM then begin again with stage 1. A complete sleep cycle takes an average of 90 to 110 minutes, with each stage lasting between 5 to 15 minutes. The first sleep cycles each night have relatively short REM sleeps and long periods of deep sleep [stage 3] but later in the night, REM periods lengthen and deep sleep time decreases.
What is the distribution of sleep stages?
In adults, approximately 5% of the total sleep time is Stage N1; 50% Stage N2; and 20% is Stage N3 sleep. The remaining 25% is REM stage sleep
