Sleep Disorders

MODULE F

Types of Sleep Disorders

• 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:• 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

• 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

• 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

• 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• Upper body obesity• Neck size #17 or larger in men• Neck size #16 or larger in women• Hypertension• C/O daytime sleepiness

Pickwickian Syndrome

• 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

• 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