SLEEP DISORDERED BREATHING/ OBSTRUCTIVE SLEEP APNEA

JHANSI NALAMATI MD

TYPES

Obstructive Sleep Apnea

Central Sleep Apnea

Mixed Apnea

Upper Airway Resistance Syndrome (UARS)

                                                                                                                                        

                                                                                                                                      

                                                                                                                                       

Historical background

Apnea- literally means “without breath”

Pickwickian papers fat boy “Joe”

Osler and later Burwell applied the name “Pickwickian Syndrome” to patients with Obesity, Hypersomnolence and signs of Chronic hypoventilation

Historical (contd.)

Sleep apnea -Rediscovered by Gestaut and co- workers in 1965 by simultaneously recording sleep and breathing in a “Pickwickian” patient and described all 3 types of apnea.

Postulated that sleepiness is due to repetitive arousals associated with resumption of breathing that terminated the apneic events.

Historical(contd.)

First description of successful Tx of OSA by tracheostomy followed in 1969.

First Tx with CPAP – in 1980’s soon after NIPPV was described by Charles Collins of Australia

Definition of Apnea

Apnea-Cessation of breathing(air flow) for 10 seconds

Hypopnea- decreased in the airflow by 30-50%, and associated with an arousal and a drop in oxygen desaturation by 3-4%

Prevalence

9% of men and 4% of women, in one study of state employees had AHI of 15 events/hr

12 million people in the US have OSA

Pathophysiology

Pharynx is abnormal in size or collapsibility.

As an organ for speech and deglutition it must be able to change shape and close

As a conduit for airflow it must resist collapse

Pathophysiology(contd.)

Exact mechanism is not knownDuring the day muscles in the region keep the airway openDuring sleep muscles relax to a point where the airway collapses to an extent that it gets obstructedOnce breathing stops, individual awakens to breathe and arousal can last few seconds to a minute

                                          

                                         

Risk factors for OSA

Obesity

Age- middle aged men and post- menopausal women

Older age- due to loss of muscle mass and tone

? Family Hx of OSA

Risk factors (contd.)

Anatomic abnormalities- receding chin, ?Nasal congestion, ? DNS

Enlarged Tonsils and adenoids esp.in children

Enlarged and inflammed uvula, worsened by chronic smoking, GERD

Acromegaly

Risk factors (contd.)

Amyloidosis, post- polio syndrome, neuromuscular disorders

Marfan’s syndrome, Down’s syndrome

Use of alcohol and sedatives that relax the upper airway

Increased neck circumference > 16 inches in women and 18 inches in men

                

              

                             

             

          

                              

Symptoms

Most of the symptoms are from disruption of normal sleep architecture

Excessive Daytime Sleepiness (EDS)- falling asleep even in stimulating environment, during a conversation, eating, business meeting

H/O Snoring

Symptoms (contd.)

Non- restorative sleep

Automobile Accidents

Personality changes

Decreased Memory

Erectile Dysfunction

Frequent Nocturnal Awakening

Symptoms(contd.)

Drowsy Driver Syndrome

Polyuria

Early morning headache

Dry mouth

Signs

Loud Snoring

Witnessed apneas

Obesity

HTN

Metabolic syndrome

Increased Neck circumference

Anatomic Abnormalities

SHHS

Sleep heart health study- initiated by NIH in 1996 and initial data shows that treatment of SBD improved outcomes in control of HTN, CHF atherogenesis, glycemic control

Screening for OSA

2 of the three symptoms- EDS, loud Snoring, Witnessed Apneas

High Score on ESS(Epworth Sleepiness Score)>12, or Stanford Sleepiness Score

Epworth Sleepiness Scale (ESS)

Maxiumum score of 24The scale is used to rate the 8 situations below that apply best to each individual0-no chance of dozing1- Slight chance of dozing2- moderate chance of dozing3- high chance of dozing

ESS (contd.)

Sitting and readingWatching televisionSitting inactive in a public place ( theater, meeting)As a passenger in a car for about an hr. without breakLying down to rest in the afternoon when circumstances permitSitting and talking to someoneSitting quietly after lunchIn a car, while stopped for a few minutes in traffic

ESS ( contd.)

1-6 : getting enough sleep

7-9 about average and probably not suffering from Excessive daytime Sleepiness (EDS)

10 or greater- need further evaluation to determine the cause of EDS or if you have underlying sleep disorder

Types of Sleep Study

Full night Polysomnography ( PSG)

PSG with CPAP titration

Split- Night Polysomnography

Multiple Sleep latency test ( MST)

Maintainance of wakefulness Test ( MWT)

Diagnosis

Nocturnal Polysomnography-in lab study, where EEG, EMG, HR, body position, leg movements, Oximetry, Snoring, abdominal and chest wall movements are recorded

Home studies are limited as EEG is not recorded, or in some limited studies only Nocturnal Pulse oximetry is done

Definition of OSA

Normal- AHI < 5

Mild OSA- AHI 5-20

Moderate OSA- AHI 20-40

Severe OSA- AHI 40-60

RDI( respiratory disturbance Index)- AHI+ RERA( Respiratory Effort Related Arousals)

UARS

Upper Airway Resistance Syndrome

Cannot be diagnosed with PSG

Repetitive arousals that probably result from increased Respiratory effort and high resistance in the airway

Can be diagnosed by measuring esophageal pressure (Pes)

Medical Complications

Uncontrolled HTN

Diminished quality of life from chronic sleep deprivation

Increase risk for CVA

Worsening of CAD and CHF

Treatment

Behavioral Tx- weight loss

Sleep hygeine

Avoiding alcohol too close to bedtime

Avoid sedatives and hypnotics, narcotics

Avoid caffeine

Treatment(contd.)

Positional Tx- helpful with Primary snoring

Positive Airway pressure (CPAP or BiPAP)

ENT Surgery

Oral appliances

Positive airway pressure

Effective, Non-invasive

Mask fit, air seal, comfort and humidification are important

Nasal mask, full face- masks, nasal pillows, Nasal aire prongs

Complications of CPAP

Local dermatitis

Air leak, nasal congestion,rhinorrhea

Dry eyes

Nose bleed

Aerophagia

Rare- tympanic rupture, pneumothorax

Compliance is the biggest issue

Surgery

Except tracheostomy,helps only mild to moderate cases or only primary snoring

Not curative for OSA

Somnoplasty- office procedure- radiofrequency ablation of the soft palate- only for snoring

Surgery( contd.)

LAUP- laser assisted uvuloplasty, only for snoring, office procedure

UPPP (UP3)- (Uvulo-palato-pharyngo-plasty)

Complicated surgery

Patients have to observed in the hospital overnight

UPPP(contd.)

Decreases AHI by only 50%

Complications include- nasal regurgitation of fluids, pharyngeal stensosis

In children- tonsillectomy and adenoidectomy alone is curative

Jaw surgery

Useful for retrognathia, involves partial excision of maxilla or mandible

Genioplasty

Complicated surgery

Bariatric surgery

Gastric bypass

Weight loss and decrease in adipose tissue of the parapharyngeal region leads to improvement or cure of OSA

Weight loss has to be at least 20-30lbs before any change in AHI can be seen

Oral appliances

Devices that are worn during sleep that retract the jaw and alleviate upper airway obstruction

Tongue retaining devices for people with macroglossia

Jaw Positioning Devices

21

Alternative Surgeries for Obstructive Sleep Apnea (Osteotomies)

1) Bi-maxillary advancement 2) Genio-tuberule advancement

CPAP Therapy

CPAP Therapy

Positive impact on subjective sleepiness and depression (in RCTs)

Fatigue, generic health related quality of life, vigilance, driving performance are all improved ( prospective trials)

These parameters are sensitive to Tx duration and compliance

Commercial driving and OSA

OSA has to be effectively treated before clearing the patient for work

Objective documentation of regular CPAP use and testing by Multiple sleep latency test and/or MWT( Maintainance of Wakefulness Test)