SLEEP APNEA

1
Sleep study

• DR SMITA AGALE

2
sleep

• This is a complex topic that we only partially
  understand.
• Humans need 6-8 hours of sleep every night, but
  individuals vary in their need for sleep.
• During sleep, we rest and repair our muscles and
  organize our thoughts and memories.
• We spend about 1/3 of our lives asleep.
• Average 3,000 hours of sleep per year.

3
(No Transcript)
4
Why we need to know about sleep study
5

• 70 million people suffer from sleep disorders.
• 70 are primary sleep disorders
• Up to 50 of these are related to Sleep
  disordered breathing
• It costs millions of dollars in health care per
  year
• At least 2300 sleep studies/ 100000 people/year
  needed to adequately address the demand for
  diagnosis and treatment.

6
in sleep deprived

• Snoring, gasping/choking, stop breathing at night
• Daytime sleepiness or tiredness
• Drowsy driving
• Morning headaches, dry mouth, sore throat
• Decreased sex drive, waking up often to urinate
• Mood, memory, attention problems, drowsy driving
• Twitching and jerking in limbs at night
• Difficulty falling or staying sleep

7
Stages of Sleep

• Stage W (Wakefulness)
• Stage NREM
• Stage N1
• Stage N2
• Stage N3/N4
• Stage R (REM)

8
(No Transcript)
9
Wake
10
Stage N1 sleep
11
Stage N2 sleep
12
Stage N3/4 sleep
13

• Normal sleep consists of 4 - 6 cycles of NREM
• sleep alternating with REM sleep every 90-120
  minutes
• First two cycles are predominantly NREM
• Later stages (early am) are predominantly REM

14
Stage REM sleep
15
(No Transcript)
16
Sleep disorders

• Dyssomnias
• Difficulty getting enough sleep
• Problems in the timing of sleep
• Complaints about the quality of sleep

• Parasomnias
• Abnormal behavioral physiological events during
  sleep
• e.g. nightmares, sleep walking, sleep talking

17

• Dyssomnias -
• Three subcategories intrinsic (i.e., arising
  from within the body), extrinsic (secondary to
  environmental conditions or various pathologic
  conditions), and disturbances of circadian
  rhythm.5
• Insomnia
• Primary hypersomnia. Hypersomnia of central or
  brain origin.
• Narcolepsy A chronic neurological disorder (or
  dyssomnia), which is caused by the brain's
  inability to control sleep and wakefulness.7
• Idiopathic hypersomnia
• Recurrent hypersomnia - including KleineLevin
  syndrome
• Posttraumatic hypersomnia
• Menstrual-related hypersomnia

18

• Parasomnias -abnormal and unnatural movements,
  behaviors, emotions, perceptions, and dreams in
  connection with sleep.
• REM sleep behaviour disorder
• Sleep terror (or Pavor nocturnus)- Characterized
  by a sudden arousal from deep sleep with a scream
  or cry, accompanied by some behavioral
  manifestations of intense fear.9
• Sleepwalking (or somnambulism)
• Bruxism (Tooth-grinding)
• Bedwetting or sleep enuresis.
• Sleep talking (or somniloquy)
• Sleep sex (or sexsomnia)
• Exploding head syndrome - Waking up in the night
  hearing loud noises.
• Medical or psychiatric conditions that may
  produce sleep disorders
• Psychosis (such as Schizophrenia)
• Mood disorders
• Depression
• Anxiety
• Panic
• Alcoholism
• Sleeping sickness - a parasitic disease which can
  be transmitted by the Tsetse fly.

19

• Sleep disordered breathing (SDB), including (non
  exhaustive)
• Several types of Sleep apnea
• Snoring
• Upper airway resistance syndrome
• Restless leg syndrome
• Periodic limb movement disorder
• Circadian rhythm sleep disorders
• Delayed sleep phase disorder
• Advanced sleep phase disorder
• Non-24-hour sleepwake disorder

20
Respiratory sleep disorders

• Snoring
• OSA
• OSAH syndrome
• UARS- upper airway resistance syndrome
• OHS- obesity hypoventilation syndrome
• Overlap syndrome
• Pediatric OSA syndrome

21
RISK FACTORS

• Obesity 70 OSA
• Male sex
• Aging
• Postmenopasual state
• Black race
• Alcohol
• smoking

22

• Sleep apnea is a chronic respiratory sleep
  disorder characterized by recurrent episodes of
  partial or complete upper airway obstruction
  during sleep (apneas, hypopneas) and are
  associated with repeated disruption of sleep
  resulting in excessive daytime somnolence and
  other medical co-morbidities.

23
Respiratory events

• Apnea ( obstructive, central, mixed)
• Hypopnea respiratory effort- related arousal
  (RERA)
• Hypoventilation
• Cheyne-stokes brathing

24

• Apnea A pause in breathing during sleep that
  lasts at least 10 seconds. It involves a
  reduction in airflow of 90 or more. This is
  measured by thermal sensors.
• If respiratory effort present--- obstructive
• If no respiratory effort present --- central
• If it start out without respiratory efforts but
  present in latter part of event then -- mixed

25
(No Transcript)
26
Hypopnea

• A partial reduction in breathing of at least 30
  that lasts at least 10 seconds during sleep. This
  is measured by a nasal pressure transducer.
• Apnoea-hypoponea index AHI is an average of the
  combined episodes of apnoea and hypopnoea that
  occur per hour of sleep

27

• RERA-respiratory effort-related arousals
• a period of 10 sec of increasing respiratory
  effort or flattening of nasal pressure amplitude
  leading to an arousal from sleep that dose not
  meet the criteria for apnea or hypopnea
• RID- respiratory disturbance index
• RDI (Apneas hypopneas RERA)/hr of sleep

28
Criteria for OSA

• AHI gt 5/hr associated with symptoms
• Or an AHI gt 15/hr with or with symptoms
• Some diagnostic criteria used RERA i.e. score
  able respiratory events (apnoea, hypopnea or
  RERA) of 5/hr

29
Grads of OSA

• Mild OSA AHI gt 5-15
• Moderate OSA AHI gt 15-30
• Sever OSA AHI gt 30

30
Polysomnographic findings of OSA

• EEG FINDINGS
• Increased stage N1
• Reduced stage N3
• Reduced stage R (REM sleep)
• Increased respiratory arousals

31
Respiratory findings

• Snoring
• Obstructive, mixed apneas, and central apneas
• Obstructive hypopneas
• AHI mild 5 to lt15/hr, moderate 1530/hr, severe
  gt 30/hr
• AHI supine gt 2 AHI nonsupine postural OSA
• AHI REM gt AHI NREM common
• Apnea duration REM gt NREM

32
Arterial oxygen desaturation

• Lowest SaO2 during REM sleep
• Longest REM periods in the early morning hours
  typically have the worst desaturation

33
Cyclic variation in heart rate

• Slowing of heart rate at apnea onset and speeding
  at event termination.

34
snoring
35
Snoring

• Snoring is the act of breathing with a grunting
  or snorting sound while asleep
• A vibratory sonorous noise made during
  inspiration less commonly expiration. It is
  associated with a vibration( flattering of soft
  palate) other pharyngeal structure
• Snoring is caused by obstructed airflow through
  the nose and throat.
• Simple snoring audible snoring
• -patient has no
  complaints of insomnia, excessive
  daytime sleepiness or sleep disruption

36
snoring

• British survey 40 of population surveyed
  snored Malefemale was 21
• US study 44 of males and 28 females ages
  30-60 yrs old

37

• Noisiness in snoring is related to obstruction of
  the airflow at one or more locations
• The nose
• The soft palate and uvula
• The base, or back part, of the tongue
• The tissues on the sidewalls of the throat
• Snoring is typically worse when lying on the back
  due to gravity effects

38
(No Transcript)
39

• Dryness in the nose and throat slows down airflow
  and prevents re-opening of the throat
• Medicines that dry out the mucus membranes
• Dry air in the winter
• Mechanical blockage in the nose (polyps, deviated
  nasal septum)
• Allergies, colds, or sinusitis
• Tobacco abuse dries out mucosal surfaces

40
Upper airway resistance syndrome

• Respiratory event related arousals during sleep
  associated with excessive daytime sleepiness. No
  apneas or hypopneas
• i.e. AHI lt5
• Or respiratory arousal index( RAI) gt 10/hr this
  not associated with desaturation or change in
  thermal device-detected airflow.

41
Obesity hypoventilation syndrome

• Most patient with OSA do not have day time
  hypoventilation
• OHS- obesity hypoventilation syndrome
• Overlap syndrome- COPD OSA

42
(No Transcript)
43
Obesity hypoventilation syndrome

• Daytime pco2 gt45 BMI gt 30kg/m2
• Suspect OHS if HCO3 gt 27 mEq/L (especially
  without reason for metabolic alkalosis)
• High mortality if untreated
• 80-90 of OHS patient have OSA
• Sever nocturnal desaturation
• 100 sleep related hypoventilation
• Cor pulmonale- common

44
Overlap syndrome

• Chronic obstructive pulmonary disease (COPD) and
  OSA are both common diseases affecting
  respectively 10 and 5 of the adult population
  over 40 years of age.
• and their coexistence, which is denominated
  overlap syndrome, can be expected 0.5 of this
  population.
• COPD alone rarely retain CO2 until the FEV1 is lt
  1.0 L or lt 40
• Pt with OSA mild to mod COPD retain co2

45
Saw tooth appearance
46
Complication of OSA

• Some medical problems caused by OSA include
• Elevated blood pressure
• Cardiac arrhythmias
• Pulmonary hypertension

47
What is the impact of SDB

• Road traffic accidents- mortality
• Lower productivity at school and work
• Morbidity-Impaired immune function, HTN, insulin
  resistance, stroke, pulm HTN, poor asthma
  control, ventricular arrhythmias and sudden death
• Neurocognitive and mood dysfunction
• Reduced quality of life

48
Management

• Investigation
• History
• examination
• Treatment
• Non surgical/medical
• surgical

49
Stanford sleeping scale
50
(No Transcript)
51
STOP-BANG

• Snoring, tired, observed,(blood) pressure, body
  mass index, age, neck circumference, age, gender
• Sensitivity 84,92,100 for AHI cutoff of
  greater than 5/hs,15/hr 30/hrs respectively.

52
Physical examination

53

• Mallampatticlassification

54

• Size of tonsils presence of macroglossia
• Septal deviation, external nasal deviation,
  inflamed mucosa, patency of nares
• Craniofacial-retrognathia or micrognathia
• Neck- Neck circumference gt17 inches in men and
  gt16 inches in women is risk factor

55
Systemic examination

• CVS- signs of Rt heart failure( rt ventricular
  heave, loud P2), lt ventricular failure(S3,S4)
• RS- obstructive airway disease or neurological
  disease( diaphragmatic paralysis)
• Abdo-hepatomegaly
• Extremity-peripheral edema, clubbing or cyanosis

56
Polysomnography (PSG)
57
Types of sleep studies

• Diagnostic - investigative study to determine if
  there are identifiable problems with the
  patients sleep
• CPAP titration - once a patient is identified as
  having sleep apnea, another study is performed in
  which the technician adjusts the CPAP/BiPAP level
  during the test and decides which mask and type
  of treatment is best

58

• Split Night - combines a diagnostic study and a
  titration study into one night. The patient is
  diagnosed during the first half of the night
  CPAP/BiPAP applied the second half if required by
  protocol
• MSLT - Multiple Sleep Latency Test (nap study)
• MWT Maintenance of Wakefulness Test

59
(No Transcript)
60
Four types diagnostic study

• Type 1standard, attended in- laboratory,
  measuring all physiological parameters
• Type 2- record variable as type 1 studies nut do
  not req the presence of sleep technician, nor
  they req that pt spent night in sleep lab
• Type 3- at least 4 physiological parameters
  respiratory efforts/ airflow, HR, EKG oxygen
  saturation
• Type 4- at least 3 parameters

61
Sleep Staging Variables

• Electroencephalogram (EEG) - acquired by surface
  electrodes on the scalp at standardized locations
  (10-20 system)
• Electrooculogram (EOG) - acquired by surface
  electrodes placed at the outer canthus of each
  eye
• Electromyogram (EMG) - acquired by surface
  electrodes placed on the chin muscle (sub-mental)

62
Channels commonly recorded during a PSG

• Brain wave activity (EEG),
• Eye movement (EOG),
• Muscle tone (chin EMG),
• Airflow via thin catheters placed in front of
  nostrils and mouth
• Breathing effort via belts placed over chest and
  abdomen
• Snoring (microphone placed over the neck)
• heart rhythm (EKG)
• Oxygen level (SpO2)
• Leg muscle activity (PLM)
• Body position
• Video recording
• Intercom to communicate with technician

63
(No Transcript)
64
10-20 EEG Locations
65
EOG Electrode Placement

• EOG records voltage changes caused by eye
  movement
• One electrode placed on right upper outer part,
  while other one is placed on left outer lower
  cantus

66
EMG Placement

• Submental (chin)
• AASM placement one midline and two under the
  chin

67
EMG

• Recorded as the potential between two surface
  electrodes placed several centimeters apart
• Typically, the chin (submental) muscle is used
  because it exhibits large differences during
  sleep, aiding in the identification of stages
• Wake - high activity
• Sleep - lower activity
• REM sleep - paralysis of skeletal muscles

68
Respiratory variables

• Respiratory effort (thoracic and abdominal)
• Airflow (thermistor, thermocouple, nasal
  pressure, ETCO2)
• SpO2
• Snoring sounds
• Optional signals
• ETCO2
• tcCO2

69
Other Respiratory Variables

• Gases
• SpO2 Blood oxygen level () by oximetry
• tcCO2 Transcutaneous CO2
• etCO2 End Tidal CO2
• Arterial CO2 blood analysis

70
(No Transcript)
71
Typical Polysomnogram
72
Obstructive Apnea
73
Central Apnea
74
Mixed Apnea
75
hypopnea
76
Arousals

• Abrupt shift of EEG frequency
• Lasts at least 3 seconds
• At least 10 seconds of prior stable sleep
• During REM requires concurrent increase in chin
  EMG lasting at least one second

77
REM Arousal
78
ECG Reporting

• Average heart rate during sleep
• Highest HR during recording/sleep
• Bradycardia lt 40 bpm (lowest observed)
• Sinus Tachycardia gt 90 bpm (highest observed)
• Narrow Complex Tachycardia (highest observed)
• Wide complex Tachycardia (highest observed)
• Asystole, longest pause
• Atrial fibrillation
• List other arrhythmias

79
PLMS

• Repetitive (at least 4) episodes of muscle
  contraction (0.5-10 s duration)
• Minimum amplitude increase of 8 uV above baseline
• Separated by gt 5 seconds, but not more than 90
  seconds
• Arousals sometimes associated with the movements
• Positive diagnosis if more than 5 per hour of
  sleep
• Movements may be clinically significant only if
  associated with arousals

80
Example - PLMS
81
Sleep architecture

• What was the sleep efficiency?
• What was the percent of each stage of sleep?
• What was the sleep onset time?
• What was the REM onset time?

82
Respiratory Events

• Which events were most common?
• Were there any obstructive events?
• What was the AHI (Apnea/Hypopnea Index)?
• What was the RDI (Respiratory Disturbance Index)
  Apnea Hypopnea RERA per hour of sleep
• What was the nadir and baseline SpO2?
• Was any snoring recorded?

83
Leg Movements

• Were they periodic?
• What was the index (number per hour of sleep)
• Did they cause arousals?

84
Arousals

• How many per hour?
• Related to events??
• Respiratory events
• Leg movements
• Esophageal reflux
• Seizures
• Unknown (spontaneous)

85
CPAP/BiPAP

• Effective?
• Best pressure?
• Best mask?
• Tolerance?

86
Treatment

• Behavioral methods
• Nasal patency
• Dental appliances
• Positive airway pressure device
• Surgery

87
BEHAVIORAL METHODS

• Weight loss
• Avoid alcohol and sedatives
• Avoid sleep deprivation
• Avoid supine sleep position
• Stop smoking

88
Modes of positive pressure devices

• CPAP- cont pressure during inhalation
  exahalation
• BPAP- (s mode) IPAP
• EPAP
• IPAP-EPAP PS
• BPAP better tolerated in pt with difficulty
  exhaling on CPAP

89

• APAP auto-titrating titrates bet maximum
  minimum pressure limit to prevent apnea,
  hypopnea, snoring
• Auto BPAP- the physician sets the min EPAP the
  min max pressure support (IPAP-EPAP) MAX
  IPAP. The min PS 3 cm H2o by default.
• Machine adjusts both EPAP IPAP to maintain an
  open airway.

90
BPAP

• BPAP with backup rate (NPPV) BPAP modes
• ST
• T
• ASV- Adaptive seroventilation
• variant of BPAP to treat
  cheyne-strokes central apnea in congestive
  heart failure.
• EPAP set to eliminate airway obstruction.
  IPAP-EPAP difference (PS) auto adapts bet minimum
  maximum level to stabilize ventilation
• backup rate available

91
CPAP

• Splints open airway during sleep
• Reduces blood pressure
• Improves heart function (in pts with CSA)
• Do not always need titration study
• Needs to be used at least 6 hrs nightly
• Medicare guidelines AHIgt15 for 2 hr sleep test
  or AHIgt5 with sleepiness, impaired cognition,
  HTN, IHD or h/o CVA

92
CPAP

• Compliance poor in gt40 of pts but best when
  significant daytime sleepiness present
• decrease tolerance of CPAP -nasal and sinus
  congestion, conjunctivitis, noise,
  claustrophobia, mouth leak etc
• Humidification and regular follow up, help
  compliance

93
(No Transcript)
94

• Chinstraps
• Sleep Angel closes the mouth so you are forced
  to breathe through the nose
• Special pillows
• Reposition the head to open the airway more
• Snore spray
• Lubricates the mucus membranes

• Feedback alarms
• Wake you slightly when you snore
• Ear plugs
• Allow bed partner to ignore problem
• Separate rooms
• Bed partner physically moves to avoid noise
• Breathe right
• Helps nasal breathing

95
(No Transcript)
96
(No Transcript)
97
ORAL APPLIANCES
98
(No Transcript)
99
(No Transcript)
100

• Surgery to correct the airway obstruction
• Septoplasty/turbinoplasty
• Tonsillectomy
• Uvulopalatopharyngoplasty
• Tongue base surgery
• Genioglossus advancement
• Tracheotomy
• Maxillary-mandibular advancement
• Not all surgeries are for everyone. Some only
  work on certain types of obstruction
• More invasive surgeries have been more effective

101
(No Transcript)
102
(No Transcript)
103
(No Transcript)
104
(No Transcript)
105
Last but not least

• Indentify the peoples with sleep deprivation from
  normal individuals
• Identifies other associated co- morbities
• Appropriate investigations, sleep study
• Appropriate measures like mouth devices, CPAP,
  BIPAP, surgeries
• Treat the patient not the symptoms.

106
Sleep well