This document provides an overview of obstructive sleep apnea (OSA), including its definition, risk factors, diagnostic criteria, and treatment options. OSA is characterized by recurrent collapse of the upper airway during sleep, which can cause fragmented sleep, hypoxemia, and increased cardiovascular risk. Diagnosis involves assessing symptoms, risk factors, and using an overnight sleep study to determine the apnea-hypopnea index. Treatment options depend on severity but may include lifestyle changes, oral appliances, or CPAP.

1. OBSTRUCTIVE SLEEP APNOEA
clinical approach
Dr. W A P S R Weerarathna
Registrar in Medicine
WD 10/02-THJ

2. Objectives…
 Obstructive respiratory events
 OSA-introduction/clinical definition
 Pathogenicity
 At risk individuals for OSA
 Associations
 Screening & assessment of OSA
 Complications/Clinical features
 EDS & SDB
 ESS
 OSA diagnostic criteria
 OSA evaluation & diagnostic work-up
 OSA management strategies
 Summary
 References

3. What is OSA????

4. Obstructive respiratory events
 Apnea is defined by the American Academy of Sleep
Medicine (AASM) as the cessation of airflow for at
least 10 seconds.
a. Hypopnea is defined as a recognizable transient
reduction (but not complete cessation) of breathing
for 10 seconds or longer,
b. a decrease of greater than 50% in the amplitude of
a validated measure of breathing, or
c. a reduction in amplitude of less than 50%
associated with oxygen desaturation of 4% or
more.

5.  Respiratory effort–related arousal (RERA)
is an event characterized by increasing respiratory
effort for 10 seconds or longer leading to an arousal
from sleep but one that does not fulfil the criteria for
a hypopnea or apnea.

6.  Obstructive events are characterized by continued
thoracoabdominal effort in the setting of partial or
complete airflow cessation,
 Central events by lack of thoracoabdominal effort in
this setting.
 Mixed events have both obstructive and central
features.
 They generally begin without thoracoabdominal
effort and end with several thoracoabdominal efforts
in breathing.

7. OSA-Introduction
 OSA is a sleep disorder that involves cessation or
significant decrease in airflow in the presence of
breathing effort.
 It is the most common type of sleep-disordered
breathing (SDB) and
 Characterized by recurrent episodes of upper
airway (UA) collapse during sleep

9.  A common disorder affecting at least 2% to 4% of
the adult population and is increasingly recognized
by the public.
 obstructive sleep apnea should be considered as a
continuum of disease, i.e., a spectrum of
abnormalities from snoring to obesity-hypoventilation
syndrome
 Due to repetitive collapse of the upper airway:
A. sleep fragmentation,
B. hypoxemia,
C. hypercapnia,
D. marked swings in intrathoracic pressure
E. increased sympathetic activity

10. OSA-clinical definition
 The occurrence of daytime sleepiness, loud snoring,
witnessed breathing interruptions, or awakenings
due to gasping or choking in the presence of at least
5 obstructive respiratory events (apneas, hypopneas
or respiratory effort related arousals) per hour of
sleep.
 The presence of 15 or more obstructive respiratory
events per hour of sleep in the absence of sleep
related symptoms is also sufficient for the diagnosis
of OSA due to the greater association of this severity
of obstruction with important consequences such as
increased cardiovascular disease risk.

11. OSA-Patogenicity
 OSA is caused by soft tissue collapse in the pharynx
 Transmural pressure is the difference between
intraluminal pressure and the surrounding tissue
pressure.
 If transmural pressure decreases, the cross-
sectional area of the pharynx decreases.
 If this pressure passes a critical point, pharyngeal
closing pressure is reached.
 Exceeding pharyngeal critical pressure (Pcrit)
causes tissues collapsing inward.
 The airway is obstructed.

12. OSA-at risk
 Patients at High Risk for OSA Who Should Be Evaluated
for OSA Symptoms-
a. Obesity (BMI > 35)
b. Congestive heart failure
c. Atrial fibrillation
d. Treatment refractory hypertension
e. Type 2 diabetes
f. Nocturnal dysrhythmias
g. Stroke
h. Pulmonary hypertension
i. High-risk driving populations
j. Preoperative for bariatric surgery

13. OSA-associations
 Hypothyroidism (macroglossia ,increased soft tissue
mass ,myopathy)
 Neurologic syndromes ( postpolio syndrome,
muscular dystrophies, and autonomic failure
syndromes such as Shy-Drager syndrome)
 Stroke
 Acromegaly (macroglossia and increased soft tissue
mass)
 Environmental exposures (smoke, environmental
irritants or allergens, and alcohol and hypnotic-
sedative medications)

14. OSA-screen/routine evaluation
 Questions about OSA that Should Be Included in
Routine Health Maintenance Evaluations
a. Is the patient obese?
b. Is the patient retrognathic?
c. Does the patient complain of daytime sleepiness?
d. Does the patient snore?
e. Does the patient have hypertension?

15. OSA-detailed assessment
 OSA Symptoms that Should Be Evaluated during a
Comprehensive Sleep Evaluation
a. Witnessed apneas
b. Snoring
c. Gasping/choking at night
d. Excessive sleepiness not explained by other factors
e. Nonrefreshing sleep
f. Total sleep amount
g. Sleep fragmentation/maintenance insomnia
h. Nocturia
i. Morning headaches
j. Decreased concentration
k. Memory loss
l. Decreased libido/irritability

16. OSA-complications
 Hypertension,
 Stroke, myocardial infarction,
 Cor pulmonale,
 Decreased daytime alertness, and
 Motor vehicle accidents,

17. OSA-Clinical exam
 Increased neck circumference ( > 17 inches in men, > 16
inches in women),
 Body mass index (BMI) ≥ 30 kg/m2,
 A Modified Mallampati score of 3 or 4,
 The presence of retrognathia,
 Lateral peritonsillar narrowing,
 Macroglossia,
 Tonsillar hypertrophy,
 Elongated/enlarged uvula,
 High arched/narrow hard palate,
 Nasal abnormalities (polyps, deviation, valve
abnormalities, turbinate hypertrophy)

18.  Following the history and physical examination,
patients can be stratified according to their OSA
disease risk.
 High risk should have the diagnosis confirmed and
severity determined with objective testing
 As part of the initial sleep evaluation, and prior to
objective testing, patients should receive education
regarding possible diagnoses, diagnostic steps, and
the procedure involved in any testing

19. EDS- excessive day time sleepiness
 One of the most common and difficult symptoms
 Reduces quality of life, impairs daytime
performance, and causes neurocognitive deficits (eg,
memory deficits).
 Assessed using the Epworth Sleepiness Scale
(ESS).
 This questionnaire is used to help determine how
frequently the patient is likely to doze off in 8
frequently encountered situations

20. ESS-Epworth Sleepiness Scale

21.  ESS score of 12 is associated with a greater
propensity to fall asleep on the Multiple Sleep
Latency Test (MSLT)
 ESS is useful for evaluating responses to treatment;
the ESS score should decrease with effective
treatment.

22. OSA-CVD risk
 Vagal stimulation causes bradycardia
Bradycardia and hypoxia provoke serious cardiac
rhythm disturbances i.e.
a. premature beats
b. asystole,
c. ventricular tachycardia ,
d. cardiac arrest.

23. SDB-indicies
 Apnea-hypopnea index (AHI)
The AHI is defined as the average number of
episodes of apnea and hypopnea per hour.
Respiratory disturbance index (RDI)
Defined as the average number of respiratory
disturbances (obstructive apneas, hypopneas, and
respiratory event–related arousals [RERAs]) per
hour.

24. OSA-diagnostic criteria
 Individuals must fulfill criterion A or B, plus criterion C
to be diagnosed with OSAS:
 A. Excessive daytime sleepiness that is not
explained by other factors
 B. Two or more of the following that are not
explained
by other factors:
-Choking or gasping during sleep
-Recurrent awakenings from sleep
-Unrefreshing sleep
-Daytime fatigue
- Impaired concentration

25.  C. Overnight monitoring demonstrates 5 to 10 or
more obstructed breathing events per hour during
sleep
or
 greater than 30 events per 6 hours of sleep.
 These events may include any combination of
obstructive apnea, hypopnea, or respiratory effort–
related arousals.

26. OSA-evaluation-objective testing
 An overnight sleep study,or polysomnography(PSG):
In-laboratory measurement of sleep architecture
and electroencephalographic (EEG) arousals, eye
movements, chin movements, airflow, respiratory
effort, oximetry, electrocardiographic (ECG) tracings,
body position, snoring, and leg movements ect…

27.  Routine laboratory tests usually are not helpful in
obstructive sleep apnea (OSA) unless a specific
indication is present.
 Routine radiographic imaging of the UA is not
performed.

28. PSG- procedure

29. PSG-AASM guide lines
 Sleep stages are recorded via an EEG,
electrooculogram, and chin electromyogram (EMG).
 Heart rhythm is monitored with a single-lead ECG.
 Leg movements are recorded via an anterior tibialis
EMG.
 Breathing is monitored, including airflow at the nose
and mouth (using both a thermal sensors and a
nasal pressure transducer), effort (using inductance
plethysmography), and oxygen saturation.
 The breathing pattern is analyzed for the presence of
apneas and hypopneas

30. PSG-OSA- cessation of airflow for at least 10
seconds with persistent respiratory effort

31. CSA-cessation of airflow for at least 10
seconds with no respiratory effort

32. AHI-Apnoea Hypopnoea Index
 Derived from the total number of apneas and
hypopneas divided by the total sleep time.
 Most sleep centres use a cut-off of 5-10 episodes
per hour as normal.
 5-15 episodes per hour for mild
 15-30 episodes per hour for moderate
 >30 episodes per hour for severe.

33. PM-Home testing for OSA
 3 levels of portable monitors(PM) are
 (a) level 2, a portable monitor with the same
parameters as a full attended PSG (includes EEG)
 (b) level 3, with at least 4 channels, including flow,
effort, oximetry and heart rate
 (c) level 4, with fewer than 4 channels, often
oximetry with flow or oximetry alone.
 level 3 monitors are best used to confirm the
diagnosis of OSA

34. MLST-Multiple Sleep Latency Test
 Objective measurement of excessive daytime
sleepiness (EDS)
 consists of 4-5 naps of 20-minute duration every 2
hours during the day.
 The latency to sleep onset for each nap is averaged
to determine the daytime sleep latency.
 Normal daytime sleep latency is greater than 10-15
minutes.
 OSAHS is generally associated with latencies of less
than 10 minutes.

35. OSA-Treatment options
 Mild apnoea have a wider variety of options,
 Moderate-to-severe apnoea should be treated with
nasal continuous positive airway pressure
(CPAP) or BiPAP
 Alternative theraphies- Behavioral
 Oral appliances(OA)
 Surgical therapy for UA
 Adjunctive

36. Behavioral/conservative management
 Weight loss- 10% reduction in weight leads to a
26% reduction in the respiratory disturbance index
(RDI)
 Avoidance of alcohol for 4-6 hours prior to bedtime
 Sleeping on one’s side rather than on the stomach or
back!

37. Components of Patient Education Programs
 Findings of study, severity of disease
 Pathophysiology of OSA
 Explanation of natural course of disease and associated
disorders
 Risk factor identification, explanation of exacerbating
factors, and risk factor modification,
 Genetic counseling when indicated
 Treatment options
 What to expect from treatment
 Outline the patient's role in treatment, address their
concerns, and set goals
 Consequences of untreated disease
 Drowsy driving/sleepiness counseling
 Patient quality assessment and other feedback regarding
evaluation

38. CPAP therapy
 The most effective treatment for OSA
 Increases the calibre of the airway in the retropalatal
and retroglossal regions
 It increases the lateral dimensions of the UA and
thins the lateral pharyngeal walls
 Maintain UA patency during sleep & preventing the
soft tissues from collapsing.

39. CPAP for OSA

40. CPAP-criteria in OSA
 All patients with an apnea-hypopnea index (AHI)
greater than 15 regardless of symptomatology.
For patients with an AHI of 5-14.9, CPAP is
indicated if the patient has one of the following:
 Excessive daytime sleepiness (EDS)
 Hypertension
 Cardiovascular disease.

41. CPAP-complications
 Sensation of suffocation or claustrophobia
 Difficulty exhaling
 Inability to sleep
 Musculoskeletal chest discomfort
 Aerophagia
 Sinus discomfort.
 Pneumothorax and/or pneumomediastinum (extremely
rare)
 Pneumoencephalos (isolated case report)
 Tympanic membrane rupture (rare).
 Mask-related problems include skin abrasions, rash, and
conjunctivitis
 Nasal problems can include rhinorrhea, nasal congestion,
epistaxis, and nasal and/or oral dryness.

42. OSA-surgery
 Nasal surgery (septoplasty, sinus surgery, and
others)
 Tonsillectomy ± adenoidectomy
 Uvulopalatopharyngoplasty (UPPP)
 Laser assisted uvulopalatoplasty (LAUP)
 Radiofrequency volumetric tissue reduction
 Linguaplasty
 Genioglossus and hyoid advancement (GAHM)
 Sliding genioplasty
 Maxillo-mandibular advancement osteotomy
 Tracheostomy

43. OSA-medical therapy
 Modafinil is approved by the US Food and Drug
Administration (FDA) for use in patients who have
residual daytime sleepiness despite optimal use of
CPAP.
 SSRI’s such as paroxetine and fluoxetine have been
shown to increase genioglossal muscle activity and
decrease REM sleep (apneas are more common in
REM), although this has not translated to a
reduction in AHI in apnea patients

44. General OSA Outcomes Assessment
 Resolution of sleepiness
 OSA specific quality of life measures
 Patient and spousal satisfaction
 Adherence to therapy
 Avoidance of factors worsening disease
 Obtaining an adequate amount of sleep
 Practicing proper sleep hygiene
 Weight loss for overweight/obese patients

45. OSA & associated syndromes
 Syndrome Z :
syndrome X(metabolic syndrome) + OSA.
 Overlap syndrome :
chronic obstructive pulmonary disease +OSA

46. Summary
 Obstructive sleep apnea (OSA) is a common chronic
disorder that often requires lifelong care.
 Available practice parameters provide evidence-
based recommendations for addressing aspects of
care.
 There are various options in managing OSA with
suitable patient criteria.

47. References
 Clinical guide lines for the evaluation, management
& long-term care In OSA in adults-Adult OSA task
force of the American Academy of Sleep Medicine
(AASM)

48. THANK YOU…..