Sleep Disorders
MODULE F
Types of Sleep Disorders
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Obstructive Sleep Apnea
Central Sleep Apnea
Mixed
Hypopnea
Polysomnography
• Early 1980’s sleep disorders were
acknowledged by the medical community.
• Sleep apnea
• Apnea during sleep for periods of 10 seconds
or longer with an apnea index of 5/hour.
• Patient often has 30 or more episodes over a
4-6 hour period.
• Apnea may last 20 – 90 seconds.
Hypopnea
• Decreased rate and depth of breathing.
• Monitor Respiratory Disturbance Index
(RDI).
• Number of respiratory events per hour of sleep
• Includes both apneas and hypopneas.
• Usually 10 – 15 events/hour is significant.
Stages of Sleep
• 5 stages of sleep
• Non-Rapid eye movement (Non-REM)
• Stages 1-4
• Quiet or slow wave sleep
• Rapid eye movement (REM)
• Stage 5
• Active or dreaming sleep
Stages of Sleep
• Each stage is associated with
characteristic:
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Electroencephalographic (EEG) Patterns
Electro-oculographic Patterns (EOG)
Electromyographic Patterns
Behavioral Patterns
Breathing Patterns
Non-REM Sleep
• 4 Stages
• Each progressing into a deeper sleep
• Lasts 60 – 90 minutes
• Most of the time is spent in phase 2
REM Sleep – Stage 5
• Burst of fast alpha rhythms in the EEG
tracing.
• Respiratory rate decreases and Vt
becomes shallow.
• Hypoventilation and apnea.
• Decrease in both the hypoxic and
hypercapnic ventilatory response during
REM.
• Constitutes 20 – 25% of sleep time.
REM Sleep
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Rapid eye movement.
HR becomes irregular.
Dreaming occurs.
Paralysis of movement.
• Arms, legs, intercostal & upper airway
muscles.
• Loss of muscle tone in the upper airway
results in airway obstruction.
REM Sleep
• REM lasts 5 – 40 minutes and recurs every
60 –90 minutes.
• More difficult to awake a person in REM.
40 Million People Suffer from
Abnormal Sleep
• Narcolepsy
• Parasomnias
• Nocturnal leg cramps (restless leg
syndrome)
• REM Behavior Disorders
• Insomnia
• Sleep Apnea
Polysomnography
• Overnight test done in a sleep clinic.
• 6 ½ to 7 hours
• Multiple monitors are used to assess the
patient.
• Patients are often videotaped.
Monitoring
• Respirations (nasal air-flow)
• SpO2
• Respiratory Effort
• Inductive plethysmography or esophageal
balloon
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Brain wave activity
Eye movement – electro-oculogram
Heart activity
Body position
Summary of Results
• # of apneas and hypopneas are summed
and averaged over the night-time to
calculate the average number of respiratory
disturbances per hour.
• Respiratory Disturbance Index
• SpO2 levels below 85% are indicative of
sleep apnea.
Consequences of Sleep
Apnea
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Increase MVA’s
Increase work related accidents
Poor job performance
Depression/Inability to concentrate
Family Discord
Decreased quality of life
Obstructive Sleep Apnea
• Most common of the sleep apneas.
• Partial or complete obstruction of the upper
airway during sleep.
• Absence of airflow at the nose/mouth
but inspiratory efforts are present; O2
desaturation.
• Can develop Cor Pulmonale.
Obstructive Sleep Apnea
• Symptoms
• Loud habitual snoring,
choking/gasping/snorts
• Morning headaches
• Daytime sleepiness (hypersomnolence)
• Obesity
• Hypertension
• Nocturnal enuresis
• Impotence
• Personality changes/depression
Obstructive Sleep Apnea
• Profile
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Upper body obesity
Neck size #17 or larger in men
Neck size #16 or larger in women
Hypertension
C/O daytime sleepiness
Pickwickian Syndrome
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Obesity
Excessive daytime sleepiness
Sleep apnea
Decreased pulmonary function
Chronic ventilatory failure
• Hypoxic drive
Central Sleep Apnea
• Respiratory centers of the medulla fail to
send signals to the respiratory muscles
• Cessation of airflow at the nose and
mouth, no inspiratory efforts &
desaturation of Hb
• Associated with CNS disorders
• Accounts for 10% of all sleep apneas
Mixed Apnea
• Combination of Obstructive and Central
• Begins as central apnea followed by
obstructive apnea
• Down’s Syndrome
Hypopnea
• No apnea
• Decreased depth and rate of breathing
Screening
• History
• Examination of neck
and upper airway
• Spirometry – flow
volume loop
• ABG
• Hb
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Thyroid Function
Chest x-ray
EKG
Sleep Study
CT scan of upper
airway or head
General Management
• Weight Reduction
• Behavior modification
• Avoid alcohol, sedation, smoking
• Sleep Posture
• Oxygen therapy
• Oral Appliance
General Management
• Surgical Procedures
• Laser-assisted Uvulopalatopharynoplasty
(LAUP) or UPPP
• Mandibular advancement
• Nasal operation
• Tonsillectomy
• Tracheostomy
General Management
• Non-invasive Ventilation
• CPAP – most frequently prescribed therapy
• BiPAP
• NPV – Central Apnea
• Continuous mechanical ventilation
• Medication – REM Inhibitors
• Phrenic Nerve Pacemaker – Central Apnea