Obstructive Sleep Apnea Syndrome

1. Obstructive Sleep Apnea Syndrome Robert H. Stroud, M.D. Francis B. Quinn, M.D. February 4, 1998

2. History • Charles Dickens - The Pickwick Papers • William Osler - Pickwickian Syndrome 1918 • Guilleminault - OSAS - 1973 • Fujita - UPPP - 1981 • Sullivan - CPAP - 1981

3. Epidemiology • 85% men • Prevalence - 2% in women, 4% in men • two thirds are obese • elderly • African-American

4. Pathophysiology • Bernoulli principle and Venturi effect • snoring • tissue laxity and redundant mucosa • anatomic abnormalities • decreased muscle tone with REM sleep • airway collapse

5. Pathophysiology • desaturation • arousal with restoration of airway • sleep fragmentation leading to hypersomnolence

6. Pathophysiology - complications • desaturation with compensatory polycythemia • hypercapnia with pulmonary hypertension • systemic hypertension • arrythmias

7. Evaluation • complete H&P • snoring - characteristics • daytime sleepiness

8. restless sleep personality change impaired cognitive skills weight gain morning headache nocturia/enuresis sexual dysfunction sedative use Evaluation - history

9. adenotonsillar hypertrophy nasal obstruction hypothyroidism acromegaly Down syndrome micrognathia retrognathia obesity vocal cord paralysis H&N masses Evaluation - history

10. Evaluation - physical exam • retrognathia • mouth-breathing • “tired” appearance

11. Evaluation - physical exam • Nasal obstruction - turbinate hypertrophy, polyposis, septal deviation • oral cavity and oropharynx • redundant mucosa • beefy red • elongated uvula • macroglossia • AT hypertrophy

12. Evaluation - physical exam • fiberoptic examination • Mueller’s maneuver • examine in supine position • usually difficult to localize one site of obstruction

13. Polysomnography EEG EOG submental EMG nasal and oral airflow respiratory muscle effort oxygen saturation ECG anterior tibialis EMG sleep position Evaluation

14. Evaluation - polysomnography • central, obstructive, mixed apneas • apnea - cessation of flow for 10 secs • hyponea - 50% decrease in flow or EEG arousal

15. Evaluation - polysomnography • respiratory disturbance index (RDI) - apneas + hyponeas per hour • apnea duration • degree of desaturation • sleep disturbance index - arousals per hour

16. Evaluation - radiography • lateral neck film in children • CT and MRI of limited benefit • somnofluoroscopy • cephalometrics

17. Evaluation - other studies • thyroid function tests • arterial blood gas • complete blood count • audio tape • rhinomanometry • multi sleep latency test (MSLT)

18. Treatment • raise intra-pharyngeal pressure • decrease pharyngeal closing pressure • increase muscular activity

19. Treatment • weight loss • avoid sedatives • pharmacotherapy • orthodontic devices • continuous positive airway pressure

20. Treatment - CPAP • 100% effective • titrate pressure • poor compliance - 50-80%

21. Treatment - surgical • adenotonsillectomy - preferred treatment in children • tracheostomy - cure for OSAS • used for failure of more conservative treatment • life threatening cardiopulmonary complications • alternative techniques to lessen complications

22. Treatment - surgical • Uvulopalatopharyngoplasty (UPPP) • excise excess tissue from free margin of soft palate • +/- tracheostomy • variable response - approximately 50% • +/- nasal surgery

23. Treatment - surgical • laser midline glossectomy • mandibular advancement • maxillary advancement - LeFort I osteotomy • hyoid suspension and inferior sagittal mandibular osteotomy • hyoid expansion

24. Treatment - complications • failure to achieve relief • difficult airway, anesthetic risk • decreased respiratory drive • bleeding, infection, pain • velopharyngeal incompetence • nasopharyngeal stenosis • post-obstructive pulmonary edema

25. Conclusion • life threatening complications • suboptimal treatment either due to poor response or limited compliance • good patient selection and long-term follow- up