Obstructive sleep apnea syndrome (OSAS) is a common sleep disorder characterized by repetitive collapse of the upper airway during sleep, resulting in reduced airflow and oxygen levels. It affects 14% of middle-aged men and 5% of women. Polysomnography is the gold standard test used to diagnose OSAS and measure its severity based on the apnea-hypopnea index. Positive airway pressure therapy is the primary treatment, while other options include oral appliances, surgery, and lifestyle changes. Untreated OSAS can cause serious health complications.

1. Obstructive sleep apnea syndrome
September 2023 Dr. Emad Efat
MD (chest)- Cairo University
Consultant of chest diseases-
El-Bagour specialized hospital

2. DEFINITIONS
Sleep is a normal recurring state that manifests as loss of
responsiveness to the external environment.
Humans spend approximately one-third of their lives asleep.
It is as important to our bodies as food, water and breathing, and
is vital for maintaining good mental and physical health.

3. DEFINITIONS
Obstructive sleep apnea syndrome (OSAS) is a common sleep-
related breathing disorder affecting 14% of middle-aged men and
5% of women. OSAS is characterized by repetitive upper airway
collapse during sleep, resulting in a complete (apnea) or partial
(hypopnea) obstruction in airflow, reduced oxygen saturation
levels and disruptive snoring.

4. The benefits of sleep
❑ Sleep is an essential biological function with major roles in recovery,
energy conservation, and survival.
❑ Sleep also appears to be important for vital functions such as neural
development, learning, emotional regulation, cardiovascular and
metabolic function, and cellular toxin removal .
❑ It was hypothesized that REM sleep plays a vital role in memory retention
and consolidation, removal of trivial or unwanted information, and storage
of important data from memory.
❑ Gherlin, a hormone that stimulates appetite and Leptin, a hormone that
inhibits appetite, are both involved in energy regulation and food intake.
❑ After two nights of sleep limited to 4 h in bed Gherlin is increased by 28%
and Leptin is decreased by 18% and appetites for high calorie foods is
increased
❑ Slow Wave Sleep (SWS) promotes restoration and growth of tissues of the
body: Growth hormone levels are increased during sleep, with the major
increase occurring soon after sleep onset, irrespective of the time of day
that sleep takes place.

5. Sleep architecture
❑ It refers to the basic structural organization of normal sleep.
There are two types of sleep, non-rapid eye movement (NREM)
sleep and rapid eye movement (REM) sleep. NREM sleep is
further divided into three sub-stages: stage N1, stage N2, and
stage N3.
❑ Over the course of the sleep period, NREM sleep and REM sleep
alternate cyclically every 90–120 min.
❑ Rapid eye movement sleep is stage of sleep during which muscle
tone decreases markedly; this stage is associated dreaming.

6. Sleep related breathing disorders
❑ Sleep related breathing disorders (SRBD) refer to a large spectrum of abnormal
respiratory patterns ranging from habitual snoring to obstructive sleep apnea
(OSA) and central sleep apnea, occurring while sleeping and resulting in an
abnormal reduction in gas exchange (i.e., hypoxemia)

7. Sleep related breathing disorders

8. Sleep related breathing disorders
Apnea is defined as:
1. Reduction in airflow greater than ≥ 90% of baseline, recorded by oronasal
thermistors or nasal pressure cannulas.
2. Duration ≥ 10 sec.
3. Aforementioned reduction in airflow at least 90% of the event.
An apnea can be
➢ Obstructive (absence of airflow with continued respiratory effort)
➢ Central (absence of both airflow and respiratory effort)
➢ Mixed (absence of respiratory effort at the beginning of the event
followed by increasing respiratory effort during the second half).

9. Sleep related breathing disorders
Hypopnea is defined as:
1. Reduction in airflow ≥ 30% from baseline, recorded by nasal pressure
cannulas or alternatively by induction plethysmography or oronasal
thermistors.
2. Duration ≥ 10 sec.
3. Aforementioned reduction in airflow at least 90% of the event.
4. Reduction in saturation at least ≥ 4% from baseline SpO2 % prior to the
event.

10. Sleep related breathing disorders
❑ Central sleep apnea syndrome (CSA) in adults is defined as cessation in
airflow of 10 or more seconds in the absence of any inspiratory effort.
❑ The risk factors for developing CSA have been studied primarily in the
setting of heart failure, and include male gender, older age, sedentary
lifestyle , diagnosis of atrial fibrillation, increased ventricular filling
pressure, more advanced cardiac remodeling as manifested by increased
end diastolic volume, renal failure, stroke, Post-menopausal women,
hypothyroidism and acromegaly

11. Sleep related breathing disorders

12. Sleep related breathing disorders
❑ Obesity hypoventilation syndrome (OHS): is defined as a combination of
Obesity (Body mass index (BMI) >40 kg/m2), daytime hypoventilation
characterized by hypercapnia and hypoxemia (PaCO2 > 45 mm Hg and
PaO2 < 70 mm Hg at sea level) and sleep-disordered breathing (SDB) in the
absence of an alternative cause for hypoventilation like obstructive or
restrictive lung disease, chest wall disorders like kyphoscoliosis,
neuromuscular disorders and congenital central hypoventilation

13. Obstructive sleep apnea syndrome
Severity criteria: The criteria of the severity of OSAS are a combination of the
severity of daytime sleepiness (subjective and objective (ESS)) and the value
of AHI
The apnea–hypopnea index (AHI), which is the number of apneas and
hypopneas per hour of sleep
❑ AHI = (# apneas + # hypopneas) / sleep hours
➢ AHI < 5 normal
➢ AHI 5 – 15 mild
➢ AHI 15 – 30 moderate
➢ AHI > 30 severe.

14. Obstructive sleep apnea syndrome
Risk factors:
❑ Age: increases with age.
❑ Gender: OSA more common in males.
❑ Obesity: The risk of developing OSA increases considerably at a higher
BMI.
❑ Craniofacial and upper airway abnormalities: e.g. Retrognathia and
micrognathia, Mandibular hypoplasia, Retropalatal obstruction as
Adenotonsillar hypertrophy particularly in children and High arched palate.
❑ Nasal congestion
❑ Smoking and alcohol consumption
❑ Menopausal and postmenopausal women
❑ Endocrine disorders: Hypothyroidism and acromegaly.

15. Obstructive sleep apnea syndrome
Pathogenesis of OSA:
❑ The two primary forces tending to collapse the airway are the intra-luminal
negative pressure generated by the diaphragm during inspiration and the
extra-luminal tissue pressure (that pressure resulting from tissue and bony
structures surrounding the airway

16. Obstructive sleep apnea syndrome
The Pathophysiology:

17. Obstructive sleep apnea syndrome
The Pathophysiology:
❑ Chronic intermittent hypoxia and sleep disruption are considered
important causes of cerebro-cardio-vascular diseases in OSAS patients.
❑ Chronic intermittent hypoxia and sleep disruption leads to systemic
hypertension due to the activation of the sympathetic system in patients
on a high-cholesterol diet.
❑ OSAS is also associated with insulin resistance and glucose intolerance,
which are known risk factors for atherosclerosis.
❑ It is well known that chronic hypoxia plays an important role in regulating
various stages of cancer formation and progression

18. Obstructive sleep apnea syndrome
DIAGNOSIS:
Clinical Presentation:
Symptoms
Day-time symptoms
Increased daytime sleepiness.
Daytime fatigue.
Concentration difficulties.
Morning pain in the throat.
Headache (preferably in the morning hours).
Night-time symptoms
Witnessed apneas.
Loud, frequent and intermittent snoring.
Dry mouth.
Thirsty during the night.
Nocturnal diuresis.
Choking.
Disturbed sleep.
Sweating (preferably night-time).
Family history of snoring and sleep apnea.

19. Obstructive sleep apnea syndrome
DIAGNOSIS:
Clinical Presentation:
Clinical features
• Excessive daytime sleepiness
• Non-restorative sleep
• Witnessed apneas
• Awakening with choking
• Nocturnal restlessness
• Insomnia with frequent
awakenings
• Lack of concentration
• Cognitive deficits
• Changes in mood
• Morning headaches
• Vivid, strange, or threatening
dreams
• Gastro-esophageal reflux
• Obesity
• Neck circumference equal to or
larger than 17 inches
• Systemic hypertension
• Hypercapnia
• Cardiovascular disease
• Cerebrovascular disease
• Cardiac dysrhythmias
• Narrow or "crowded" airway
• Pulmonary hypertension
• Cor pulmonale
• Polycythemia
• Floppy eyelid syndrome

20. Obstructive sleep apnea syndrome
Screening tools:

21. Obstructive sleep apnea syndrome
Screening tools:

22. Obstructive sleep apnea syndrome
Complications:
❑ Neurobehavioral and social: Mood disturbances, and cognitive
dysfunctions
❑ Gastroesophageal reflux
❑ Cardiovascular: Hypertension, myocardial infarction, stroke, Cardiac
arrhythmias and cor pulmonale
❑ Diabetes mellitus
❑ Liver: Raised liver enzymes and fibrosis
❑ Sexual dysfunction, including impotence and decreased libido

24. Obstructive sleep apnea syndrome
The physical examination may:
❑ Craniofacial and soft tissue enlargement: retrognathia, deviated nasal
septum, low-lying soft palate, enlarged uvula and base of the tongue.
❑ obesity (BMI≥28 kg/m2) and neck circumferences of ≥43 cm.
❑ The nasal examination: septal deviation, turbinate hypertrophy, nasal
polyps and other masses, and the internal nasal pathway.
❑ By nasopharyngoscopy: hypertrophy of the tongue, uvula, and tonsils, as
well as oedema of the soft palate and uvula.

25. Obstructive sleep apnea syndrome
Radiological findings:
❑ Cephalometry: using X-rays, it is possible to measure the skull base, the
position of the hyoid bone, the configuration of the mandible, the
posterior pharyngeal airspace, the dimensions of the tongue, the length
and thickness of the uvula, etc.

26. Obstructive sleep apnea syndrome
Radiological findings:
❑ Computerized tomography (CT)
❑ Magnetic Resonance Imaging (MRI)

27. Obstructive sleep apnea syndrome
Radiological findings:
Airway Assessment by ultrasound:
❑ Airway ultrasound can visualize and assess the mouth and tongue,
oropharynx, hypopharynx, epiglottis, larynx, vocal cords, cricothyroid
membrane, cricoid cartilage, trachea, and cervical esophagus
❑ Neck ultrasound parameters:
➢ Retropalatal pharynx transverse diameter
➢ Distance between Lingual Arteries
➢ Coronal mid-Tongue Base Thickness
➢ Sagittal mid-Tongue Base Thickness
➢ Lateral Parapharyngeal Wall Thickness

28. Obstructive sleep apnea syndrome
Radiological findings:
Airway Assessment by ultrasound:
Tongue base thickness (TBT) in the sagittal plane (A) and coronal plane (B). Other
markings were seen as following: mucosa covering of tongue (whitish arrows), and
geniohyoid muscle (GH), mylohyoid muscle (MH), genoidglossus muscle (GG),
acoustic shadow (AS) reflecting the mandible body (M) or hyoid bone (H) and
tongue (T)

29. Obstructive sleep apnea syndrome
Drug-induced sleep endoscopy

30. Obstructive sleep apnea syndrome
Polysomnography:
❑ Polysomnography (PSG), i.e., a sleep study, is the gold standard diagnostic
study for sleep-disordered breathing. During PSG, the patient sleeps while
connected to a variety of monitoring devices that record physiologic
variables.
❑ Indications for PSG include
➢ diagnostic evaluation of suspected OSA
➢ titration of positive airway pressure
➢ split Study
➢ repeat CPAP titration.
➢ assess Cheyne-Stokes breathing
➢ central apnea
➢ hypoventilation
➢ periodic limb movements during sleep
➢ delta (slow wave) sleep parasomnias
➢ REM sleep behavior disorder.

31. Obstructive sleep apnea syndrome
Polysomnography:
CPAP titration:
Indications :
➢ AHI > 5 / hr with symptoms.
➢ AHI > 15 / hr with or without symptoms,
Indications of Split Study:
➢ AHI > 30 /hr within 2 hours of monitoring,
➢ AHI from 15 - 30 with severe desaturation or arrhythmia (thought due
to OSA)
➢ at least 3 hours remain for the CPAP titration.
Indications to Repeat CPAP titration :
➢ Residual time for CPAP titration is < 3 hours
➢ If the patient is being treated on CPAP and is NOT doing well,
➢ if a patient on CPAP gains > 10% of body weight (to determine whether
the pressure is adequate).

32. Obstructive sleep apnea syndrome
sleep lab:

33. Obstructive sleep apnea syndrome

34. Obstructive sleep apnea syndrome
Other Tests:
Sleep diaries: is a daily record of important sleep-related information.

35. Obstructive sleep apnea syndrome
Other Tests:
Actigraphy: Actigraphs are small, wrist-worn motion, sensing devices (about
the size of a wristwatch) that measure movement generally for one week.

36. Obstructive sleep apnea syndrome
Other Tests:
Multiple sleep latency test (MSLT): to identify the early onset of rapid eye
movement sleep during the day (which is characteristic of narcolepsy). EEG is
used to measure the moment of sleep and rapid eye movement onset during
each of the sleep opportunities
The Maintenance of Wakefulness Test (MWT) indicates how alert a person is
by repeatedly measuring how well they are able to resist sleep in a dark, quiet
space. Although it is not used to diagnose sleep disorders, the MWT can help
sleep specialists identify the severity of symptoms in people experiencing
certain sleep disorders such as narcolepsy and obstructive sleep apnea

37. Obstructive sleep apnea syndrome
Treatment of OSA:
Positive Airway Pressure (PAP):
PAP may be delivered in continuous (CPAP), bi-level (BiPAP), or auto titrating
(APAP) modes. Partial pressure reduction during expiration (pressure relief)
can also be added to these modes. PAP applied through a nasal, oral, or
oronasal interface during sleep is the preferred treatment for OSA

38. Obstructive sleep apnea syndrome
Treatment of OSA:
Bilevel PAP, although more expensive than CPAP, is therefore a valid
alternative in patients intolerant to CPAP and in patients with associated
hypoventilation or chronic obstructive pulmonary disease or in patients with
severe OSA and in those requiring high treatment pressures
Adaptive servo-ventilatio (ASV) is a form of "BiPAP". The difference is that ASV
varies IPAP and/or EPAP to adjust ventilation as needed by the patient.

39. Obstructive sleep apnea syndrome
Treatment of OSA:
An oral negative pressure device: this device generates negative oral pressure
by drawing the tongue and soft palate in more anterior positions via a
mouthpiece connected to a suction mechanism

40. Obstructive sleep apnea syndrome
Treatment of OSA:
Behavioral Strategies:
Behavioral treatment options include weight loss, ideally to a BMI of 25 kg/m2
or less; exercise; positional therapy; and avoidance of alcohol and sedatives
before bedtime
Position therapy: prevent them from sleeping in the supine posture.
➢ positional pillows
➢ tennis ball technique
➢ supine alarm devices

41. Obstructive sleep apnea syndrome
Treatment of OSA:
Myofunctional Therapy:
It is composed of isotonic and isometric exercises that target oral (lip, tongue)
and oropharyngeal structures (soft palate, lateral pharyngeal wall)
Oro-facial myofunctional
therapy assigned at home: (A,
B) letter ‘O’ and ‘A’, making the
tongue adhere to the palate
and snaping it off by opening
the mouth (A–O); (C, D) nose-
chin tongue, trying to touch the
nose with the tip of the tongue,
and then, trying to touch the
chin; (E, F) tongue-cheeks, push
the tongue against the cheek,
10 times to the right, 10 times
to the left.

42. Obstructive sleep apnea syndrome
Treatment of OSA:
Nasal dilators:
There are two types of nasal dilators, an internal dilator and an external
dilator

43. Obstructive sleep apnea syndrome
Treatment of OSA:
Oral Appliances:
➢ Mandibular repositioning appliances
➢ Tongue retaining devices

44. Obstructive sleep apnea syndrome
Treatment of OSA:
Hypoglossal nerve stimulation: and continuous transcutaneous electrical
stimulation, are currently emerging and have been shown to reduce
ventilatory load and neural drive in patients with OSA

45. Obstructive sleep apnea syndrome
Treatment of OSA:
Adjunctive Therapies:
Bariatric Surgery:
Bariatric surgery, including gastric bypass and bandage, can resolve or improve
OSA and offers a significantly greater improvement than nonsurgical
alternatives

46. Obstructive sleep apnea syndrome
Treatment of OSA:
Pharmacologic Agents and Oxygen Therapy:
❑ pharmacological agents, include intranasal corticosteroids, decongestant
sprays, nicotine therapy, opiate antagonists, methylxanthine derivatives,
oestrogen and progesterone, testosterone, thyroid hormone, growth
hormone therapy for acromegaly, beta-blockers, alpha-adrenergic agonists,
leukotriene inhibitors, glutamate antagonists, acetazolamide, Serotonergic
agents, tricyclic antidepressants, physostigmine, modafinil and TNF-alpha
antagonists, in addition to supplemental oxygen, and carbon dioxide
inhalation
❑ high-flow nasal cannula (HFNC) delivery for OSA alleviated upper airway
obstruction. HFNC also reduced arousals and the apnea-hypopnea index in
adults

47. Obstructive sleep apnea syndrome
Treatment of OSA:
high-flow nasal cannula (HFNC)

48. Obstructive sleep apnea syndrome
Treatment of OSA:
Surgical Treatment:
A surgical treatment plan is made according to the site(s) of obstruction.
Surgery can consist of either soft tissue removal or a skeletal modification
Anatomic location Treatment modality Surgical procedure
Nasal cavity
Soft tissue Polypectomy, ablation of turbinate
Skeletal Septoplasty
Nasopharynx Adenoidectomy
Oropharynx
Soft tissue
Tonsillectomy, LAUP (Laser-assisted uvulopalatoplasty)
procedure; UPPP
Skeletal Rapid maxillary expansion
Hypopharynx
Soft tissue Midline glossectomy, tongue base reduction
Skeletal
Mandibular advancement, genioglossal advancement,
hyoid myotomy suspension
Oro and hypophanrynx Skeletal Maxillomandibular advancement
Bypass of the airway Tracheotomy

49. Thank you