OBSTRUCTIVE SLEEP APNOEA

SYNDROME

Prof. Mohan Kameswaran

MS, FRCS, FICS, FAMS, DSc, DLO

Madras ENT Research Foundation

Chennai

OBSTRUCTIVE SLEEP APNOEA SYNDROME

• OSA is a common disorder resulting from collapse of

the pharyngeal airway during sleep

• Significant advances have been made in the

evaluation and treatment of OSAS over the past

several years

• Primary snoring

• Upper Airway Resistance Syndrome (UARS)

• Obstructive sleep apnoea syndrome (OSAS)

SLEEP DISORDERED BREATHING

RDI O2

desaturationDay time

sleepiness

Primary snoring

< 5 / hr SaO2 > 90% No

UARS < 5 / hr SaO2 > or = 90%

Yes

OSAS > 5 / hr SaO2 < 90% Yes

SLEEP-RELATED UPPER AIRWAY OBSTRUCTION

• Apnoea - cessation of airflow at the nostrils and mouth

for atleast 10 seconds

• SAS - 30 or more apnoeic episodes during a

7-hour period of sleep or an apnoea index (number of

apnoeas per hour of sleep) equal to or greater than 5

SLEEP APNOEA SYNDROME - Semantics

• Hypopnoea (reduction in tidal volume) - 50% reduction

in airflow, lasting for 10 seconds in the presence of

continued respiratory effort

• Respiratory Disturbance Index (RDI) or Apnoea

Hypopnoea index (AHI) - number of apnoeas and

hypopnoeas per hour of sleep

• In OSAS, RDI is greater than 10

SLEEP APNOEA - TYPES

• Obstructive sleep apnoea - cessation of airflow in the

presence of continued respiratory effort

• Central sleep apnoea - no airflow at the nose or mouth

associated with a cessation of all respiratory effort

• Mixed apnoea - begins initially as central apnoea, then

becomes obstructive

• Intrinsic dyssomnia characterized by recurrent episodes

of upper airway collapse and obstruction during sleep

• Associated with recurrent oxyhemoglobin desaturation

and arousal from sleep

• Both anatomic and neuromuscular factors are important

OBSTRUCTIVE SLEEP APNOEA

Abnormal neuromuscular control of pharyngeal dilators (genioglossus, geniohyoid, palatoglossus, medial pterygoids)

during sleep

Airway narrowing (space occupying lesion from the nasal vestibule to glottis)

OSA - PATHOPHYSIOLOGY

Venturi effect Increased intraluminal negative pressure

UPPER AIRWAY OBSTRUCTION

How many people have sleep apnea?

Older guidelines (AHI > 10) - 2 - 4% of the population Older guidelines (AHI > 10) - 2 - 4% of the population

Newer guidelines (AHI > 5 with symptoms) - 9 - 24% Newer guidelines (AHI > 5 with symptoms) - 9 - 24%

Children: 1- 3%

OSAS

3 major levels of obstruction (Fujita)

• Retropalatal (Type1)

• Retropalatal and retrolingual (Type 2)

• Exclusively retrolingual (Type 3)

SLEEP MRI - Type 1 obstruction

SLEEP MRI - Type 2 obstruction

OSAS - EFFECTS

• Oxygen desaturation causing increased

sympathetic output & peripheral vasoconstriction

• High negative intrathoracic pressures with arousal

& termination of obstructive episode

• Nose - nasal polyps, DNS,

rhinitis, nasal packing

• Pharynx - nasopharyngeal

tumor, enlarged adenoids,

palatal & lingual tonsils,

retropharyngeal mass,

enlarged tongue,

micro/retrognathia

• Larynx – tumors, oedema

Shy- Drager syndrome laryngotracheomalacia vascular ring

OBSTRUCTIVE SLEEP APNOEA CAUSES

Male sex Obesity

Increasing age

Commonest etiology

• Adenotonsillar hypertrophy

• Neuromuscular hypotonia

• Craniofacial and neurologic syndromes

PEDIATRIC OSAS

OBSTRUCTIVE TONSILS

Common

• Snoring

• Excessive daytime sleepiness

• Obstructive episodes

Less common

• Morning headaches

• Personality change

• Intellectual deterioration

• Depression

• Abnormal body movements

• Frequent waking

• Nocturnal choking

• Impotence

OBSTRUCTIVE SLEEP APNOEA Clinical features

• Loud snoring

• Noisy breathing during sleep

• Mouth breathing

• Growth retardation

• Repetitive upper airway

infection

• Abnormal shyness

• Nocturnal enuresis

• Poor growth problems

• Rebellious and aggressive

behavior

• Attention deficit disorder

PEDIATRIC OSAS

Sleep MRI - Craniosynostosis

OSAS - common associations

• LPR

• Systemic hypertension

(50 - 70%)

• Coronary artery disease

• Pulmonary hypertension

• Right heart failure

• Cardiac arrhythmias

• Left ventricular hypertrophy

• MI

• Depression

• Sudden death?

• Vehicular and work-related

accidents

LARYNGOPHARYNGEAL REFLUX

OSAS - HISTORY & EXAMINATION

• General appearance, weight, height, blood pressure

• H/O alcohol, drugs e.g. sedatives

• Thyroid evaluation

• ENT & Head and Neck examination - nasal airway, tongue

size, soft palate, uvula, tonsils, naso / hypopharynx, larynx

• Craniofacial morphology

Snoring / OSAS

If OSAS, the site of obstruction

Associated problems

ENT & Head and Neck examination

• Short thick neck (Collar size > 17.5)

• Enlarged floppy uvula

• Elongated soft palate

• Tonsillar hypertrophy

• Enlarged tongue

• Micrognathia / retrognathia

• FBC, ECG, chest X-ray, Lung function tests

• Polysomnography (Holland, Dement, Raynall, 1974)

- Level 1 PSG - gold standard investigation

- Overnight monitoring of pulse oximetry, End tidal CO2, ECG, EEG, anterior

tibialis EMG, EOG, nasal & oral airflow, chest & abdominal movements &

sleeping position

- Differentiates obstructive from central sleep apnoea

- Evaluates the severity

INVESTIGATIONS

Polysomnography

Polysomnography

Sleep MRI & Fiberoptic endoscopy - assessment of

the site of obstruction - retropalatal / retrolingual /

combined

Sleep MRI

Sleep endoscopy

OSAS - TREATMENT• Medical

• Appliances - nasal splint, mandibular positioning device, tongue retaining device

• Surgical

• If anatomic obstruction is present, corrective surgery should be done

NONSURGICAL TREATMENT

• Weight loss

• Treatment of systemic disorders

• Alcohol advice

• Drugs review

NONSURGICAL TREATMENT

Drug treatment

• Protryptiline (increases the neuromuscular activity of upper

airway & decreases REM sleep)

• Theophylline

• Progesterone

• Modafinil (improves wakefulness by decreasing GABA

mediated neurotransmission)

NONSURGICAL TREATMENT• Mandibular positioning device – in non obese patients with

micrognathia / retrognathia, advances the mandible and increases

posterior airway space, has success rate of 50 % & compliance rate

of 25%

• Tongue retaining device

• Positional devices

• Nasal splints

• Nasal CPAP, Nasal BiPAP & Demand PAP

MANDIBULAR POSITIONING DEVICE

NOZOVENT NASAL SPLINT

TONGUE RETAINING DEVICE

Nasal Continuous Positive Airway Pressure (Colin Sullivan, 1981)

• Noninvasive and highly effective primary treatment

modality

• Delivers a continuous flow of air & provides a pneumatic

splint to the upper airway during inspiration preventing

collapse during sleep by increasing airway volume, area and

lateral dimensions in retropalatal and retroglossal regions

Continuous Positive Airway Pressure

Nasal CPAP

• Problems: dermal irritation, dryness, sneezing,

rhinorrhoea, claustrophobia, panic attacks leading to

noncompliance

• Auto-CPAP is as effective as constant CPAP

• The auto-CPAP is characterized by its ability to

modify the positive-pressure level applied

Nasal CPAP

• Restores normal respiration during sleep, normalizes

sleep organization

• Improves day time alertness, neuropsychiatric function,

right heart function, and systemic blood pressure

• Success rate - 90%

• Compliance - 50%

SURGICAL TREATMENT

Indications

• Primary snoring

• AHI > 15

• O2 desaturation < 90%

• AHI > 5 or < 14, with excessive daytime sleepiness

• UARS

• Unsuccessful medical treatment

• Type 1 collapse (mainly retropalatal)

• Failure of compliance for CPAP

POOR SURGICAL CASES

• Extreme obesity

• Lack of physical activity

• Alcoholism

• Type 2 collapse

• Cardiac arrhythmias

SURGICAL TREATMENT

• Nasal surgery, Adenotonsillectomy

• Uvulopalatopharyngoplasty, LAUP, RAUP, CAUP

• Hyoid advancement

• Midline Laser glossectomy

• Mandibular / Maxillary osteotomy & advancement

• Tracheostomy - gold standard

Enlargement of retropalatal airway

• Uvulopalatopharyngoplasty (UPPP)

• Laser - LAUP

• Radiofrequency - RAUP

• Coblation - CAUP

UVULOPALATOPHARYNGOPLASTY Dr. Ikematsu (1964), Dr. Fujita (1981)

• Removal of excessive redundant tissue in the oropharynx

with increased cross-sectional area

• Success rates in curing snoring: 85 - 90%

• Success rates in reducing apnoeic index: 23 - 77%

• Complications: bleeding, velopharyngeal insufficiency, dry

throat, nasopharyngeal stenosis, airway compromise,

hypernasal speech & taste disturbances

UvulopalatopharyngoplastyUvulopalatopharyngoplasty (UPPP) (UPPP)

For successful UPPP, Mandibular - hyoid angle must be less than

25 - 30

LASER ASSISTED UVULOPALATOPHARYNGOPLASTY

(Dr. Kamami, 1993)

• Effective and has the advantage of a bloodless field

• Success rates: short term - 77 - 89%

long term - 75%

no snoring - 52%

Sleep MRI – post UPPPshowing retrolingual obstruction

UPPP / LAUP - Anesthetic considerations• Pre-op evaluation

• Avoid sedatives, narcotics

• Difficult intubation (FO intubation may be required)

• After extubation - nasopharyngeal airway, pulse oximetry and

avoidance of narcotic analgesia, monitoring for post obstructive

pulmonary edema

NASOPHARYNGEAL AIRWAY

RADIOFREQUENCY IN OSAS

• Radiofrequency thermal ablation uses low levels of RF

energy to create targeted tissue ablation resulting in

tissue volume reduction

• The procedure is quick, painless and is associated with

minimal edema

Radiofrequency in OSASRadiofrequency in OSAS

COBLATION

• Voltages applied to convert conductive fluid between

electrodes and tissue into ionized vapor layer (plasma)

• Ionized layer contains excited particles which, when in

contact with tissue, break tissues molecular bonds with

minimal thermal penetration

• Energy used - up to 8 eV

Enlargement of retrolingual space

• Tongue base reduction procedures

• Mandibular osteotomy with genioglossal advancement

• Repose tongue suspension intraoral approach

• Hyoid Myotomy and suspension

• Genioglossal advancement and hyoid suspension (GAHM)

• Maxillofacial techniques

• Uvulopalatopharyngoglossoplasty (UPPGP)

(UPPP with limited resection of the tongue base)

Tongue base reduction proceduresType 3 (Riley)

• Tracheostomy required

• Midline Laser glossectomy - laser is used to extirpate a rectangular strip

(2.5 into 5 cms) of the posterior portion of tongue, useful in Down’s

syndrome, Mucopolysaccharidosis

• Lingualplasty - modification of LMG, involves additional excision of

lateral tongue tissue

• Radiofrequency tissue ablation of tongue base - RF probe with 465 KHZ

GENIOGLOSSUS ADVANCEMENT PROCEDURE

Osteotomies in the mandible at the geniotubercle advancing the insertion of genioglossus or geniohyoid by 10-14 mm & rotating it by 90%. This increases the tension placed on the tongue

CANDIDATE FOR GENIOGLOSSUS ADVANCEMENT

Tongue suspension

Tongue base is pulled forward and secured anteriorly

by a titanium screw placed at the lingual cortex of genial tubercle of mandible

MODIFIED HYOID MYOTOMY & SUSPENSION

Genioglossal advancement and hyoid suspension (GAHM)

• Combined procedure of inferior mandibular osteotomy with

genioglossal advancement with hyoid myotomy & suspension

• Success rates - 70%

• Complications: infection, need for root canal therapy,

permanent anesthesia, seroma, mandibular fracture, aspiration

Hyoid distraction procedure(Tucker Woodson)

The hyoid bone is split and two separate loops of suture

are used to pull the bone not only anteriorly and

superiorly, but also laterally

MAXILLOFACIAL TECHNIQUES

• Used in severe OSAS where the tongue base is the cause

of obstruction

• Advances the skeletal support of soft tissues (tongue and

pharynx) that collapse during sleep

Candidate for maxillomandibular

advancement

MAXILLOMANDIBULAR OSTEOTOMY & ADVANCEMENT (Riley & Powell)

• Phase 2 surgery

• Improves retropalatal and retrolingual space and increases airway

caliber in an anteroposterior direction

• Success rates: 95%

• Complications: malocclusion, inferior alveolar, lingual or

infraorbital paresthesia, nonunion/malunion, relapse of

advancement, TMJ complications, need for restorative dental work

MAXILLOMANDIBULAR ADVANCEMENT PROCEDURE (Riley & Powell)(Riley & Powell)

Presurgical evaluation

Phase I (site of obstruction)

UPPPType I oropharynx

UPPP + MOHMType 2 oro - hypopharynx

MOHMType 3 hypopharynx

Postop polysomnogram (6 months)Failure

Phase II - MMO

Riley-Powell-Stanford surgical protocol

TracheostomyTracheostomy

Bypasses airway obstruction Bypasses airway obstruction

Indications - severe OSAS with Indications - severe OSAS with • RDI above 50RDI above 50

• Lowest OLowest O22 saturation below 60% saturation below 60%

• Cardiac arrhythmiasCardiac arrhythmias

CONCLUSION

• OSA is a common disease of adult & pediatric age groups

with a myriad of presentations

• Often the patient is unaware of his condition

• A detailed history, clinical examination & simple

overnight observation will help to clinch the diagnosis

• Sleep MRI ( dynamic MRI ) with F.O.nasendoscopy

has obviated the need for cumbersome cephalometric

measures to establish the site of obstruction

• A comprehensive presurgical evaluation to identify the

site of airway obstruction improves surgical success

rates