8 Obstructive Sleep Apnea Syndrome 1
Pickwickian Syndrome Obstructive sleep apnea was called the Pickwickian syndrome in the past because Joe the Fat Boy who was described by Charles Dickens in the Pickwick papers had typical features with snoring, obesity, sleepiness.
DEFINITION • Obstructive Sleep Apnea Syndrome (OSAS) is one of the most important conditions identified in the last 50 years. • OSAS is characterized by recurrent episodes of complete or partial upper airway obstruction during sleep, usually associated with a reduction in blood oxygen saturation and daytime sleepiness (due to sleep fragmentation).
CONSEQUENCES OF SLEEP APNEA This recurrent breathing difficulty is associated with increased respiratory efforts which prevent the brain from entering the deep stages of sleep and causes: • excessive daytime sleepiness, • cognitive dysfunction, • impaired quality of life, • increased cardiovascular morbidity and mortality.
OSAS & Cardiovascular Diseases • Uncontrolled hypertension (HT) - 83% have OSAS due to activation of sympathetic drive. • Acute coronary syndrome- 40-50% has OSAS • Cardiac arrhythmias - mostly Atrial fibrillation • Heart Failure • Sudden cardiac death • Stroke
OSAS and diabetes Patients with sleep apnea and AHI>10 are much more likely to have impaired glucose tolerance and diabetes (Meslier et al Eur Respir J 2003)
Prevalence of OSAS In USA, prevalence of OSAS among middle-aged men and women were 4% and 2% (Young et al)
Predisposing Factors of OSA • male gender • age • obesity (defined by a high body mass index) • Increased waist/hip ratio • smoking • Shortening of the mandible and/or maxilla (the change can be subtle and familial) • Hypothyroidism & acromegaly by narrowing the upper airway with tissue infiltration • Myotonic dystrophy, Ehlers-Danlos
Mechanism of OSAS • The upper airway dilating muscles,like all striated muscles, normally relax during sleep. • In OSAS, the dilating muscles can no longer successfully oppose negative pressure in the airway during inspiration. • Apneas and hypopneas are caused by the airway being closed on inspiration during sleep.
Symptoms of OSA Night time • Snoring • Witnessed apnoea • Frequent nocturnal awakenings • Waking up choking or gasping for air • Unrefreshed sleep • Restless sleep • nocturia • Dry mouth • decreased libido
Symptoms of OSA Daytime • Early morning headaches • Fatigue • Daytime sleepiness • Poor memory, concentration or motivation • Unproductive at work • Falling asleep during driving • Depression
Diagnosis • A good sleep history • Assessment of obesity, • ENT • Assessment of possible predisposing causes: hypothyroidism, acromegaly and • Polysomnography: gold standard tool • Polygraphy
The Epworth Sleepiness Score How often are you likely to doze off or fall asleep in the following situations, in contrast to feeling just tired? • 0 = would never doze • 1 = slight chance of dozing • 2 = moderate chance of dozing • 3 = high chance of dozing
DIAGNOSIS OFSLEEP APNEA • To diagnose OSAS, the breathing pattern during sleep is analyzed for the presence of episodes of breathing cessation (apneas). • The total number of apneas divided by the total sleep time represents apnea index (AHI). • The cut off level for OSAS diagnosis is: AHI > 5/hour
Apnea-Hypopnea severity • AHI<5 Normal • AHI 5-15 Mild OSA • AHI 15-30 Moderate OSA • AHI >30 Severe OSA
DIAGNOSIS OFSLEEP APNEA The gold standard for diagnosis of OSAS is nocturnal polysomnography, a simultaneous recording of several physiologic parameters: • brain waves, • eye movements, • muscle activity, • chest movements, • air flow, and • blood oxygen saturation - that must be performed by trained technologists using expensive equipment
POLYGRAPHY • Airflow • Tracheal mycrophone • ECG • Thoracicbelt • Abdominal belt • Pulse-oxymeter • Tibial EMG Spitalul Clinic de Pneumologie Iasi – D.Boisteanu
NON - SURGICAL Weight loss CPAP Body position Oral appliances Drugs SURGICAL Tracheostomy UPPP Glossectomy Hyoid advancement Mandibular advancement Current Treatment for OSAS
Weight Loss • 10% weight loss predicted a 26% reduction in AHI Peppard PE et al. JAMA 2000; 284: 3015-21
Body Position • Raise head of bed • Avoid supine position Strategies • Tennis ball in pajamas • Backpacks
CPAP Therapy • Works as a pneumatic splint • 1st choice of treatment in moderate to severe OSAS • Success rate 95-100% • Long term compliance 60-70% • Retitrate pressure if needed
CPAP Therapy- Side Effects • Nasal congestion • Rhinorrhoea • Oronasal dryness Skin abrasions/ rash • Conjunctivitis from air leak • Chest discomfort • Claustrophobia
Oral Appliances □ Appropriate first-line treatment for Mild OSA, primary snoring, upper airway resistance syndrome (UARS) □ Not as effective as CPAP, 52% OSA have AHI<10% □ Young, non-obese □ Second line therapy for moderate-severe OSA □ Patient’s choice - Not tolerating / refuse to use CPAP, or are not surgical candidates MAD TRD
Oral Appliances Heinzer Esmarch Spitalul Clinic de Pneumologie Iasi – D.Boisteanu
Side Effects • Excessive Salivation • Temporo-mandibular joint discomfort • Proprioceptive malocclusion • Xerostomia • Myofacial pain Pantin et al. Sleep, 1999
Surgery • Nose: nasal surgery • UPPP (uvulo-palato-pharingo-plasty) • Retrolingual pharynx: - mandibular advancement, - lingual plasty and resection, - mandibular osteotomy, - genioglossus advancement with hyoid myotomy & suspension (GAHM), - maxillary & mandibular advancement osteotomy(MMO) • High perioperative risk
TREATMENT OF SLEEP APNEA • Nasal continuous positive airway pressure (CPAP), is the treatment of choice for obstructive sleep apnoea (OSAS) syndrome. • Treatment of OSAS by fixed positive airway pressure (CPAP) requires an in-laboratory titration procedure to determine the effective pressure level (Peff).
INSUFLATION OF AIR WITH POSITIVE PRESSURE ON A NASAL MASK MENTAINS THE PERMEABILITY OF THE NOSE AND THROAT DURING SLEEP
EFFECTIVE PRESSURE LEVEL • The effective pressure level is the one that abolishes obstructive breathing disorders, including apneas, in every sleep stage and body position. • It is usually determined during a sleep study with continuous acquisition of electrophysiologic parameters, respiratory flow, respiratory efforts and pulse oximetry.
INTELLIGENT AIRFLOW GENERATORS (1) In 1993 Berthon-Jones explored the possibility of using computer power to drive a turbine according to the analysis of physiologic signals to construct an intelligent, very fast-reacting airflow generator named auto-titrating positive pressure device (APAP).
INTELLIGENT AIRFLOW GENERATORS (2) These devices will deliver pressures only when necessary: changes of pressure will take place gradually to minimize potential sleep disruption, the unit will effectively compensate mask leaks, will detect all known variations of sleep related airway obstruction and will detect the transition from abnormal to normal breathing and reduce pressure accordingly.
INTELLIGENT AIRFLOW GENERATORS (3) The ability to respond to a variety of breathing conditions is an advantage for the patientat home becausehis respiration can change during one night (in relation to sleep position, alcohol intake, sleep stage, etc) and from night to night due to changes in weight and lifestyle.
Many patients get APAP devices for long-term treatment and can be monitored for compliance and efficacy using the memory capability in the APAP units.
CONCLUSION Both automatic (APAP) and fixed pressure (CPAP) devices are comparable in terms of patients benefit, use hours and mean pressure. Intelligent CPAPs are modern, reliable tools which allow remote monitoring of the patient in terms of treatment compliance and effectiveness, with fewer visits to the doctor andlower costs and labor.