------------------------------------------------------------------------------ TITLE: OBSTRUCTIVE SLEEP APNEA SOURCE: Dept. of Otolaryngology, UTMB, Grand Rounds DATE: SEPTEMBER 13, 1989 RESIDENT PHYSICIAN: Todd E. Samuelson M.D. FACULTY: Francis B. Quinn, Jr., M.D. DATABASE ADMINISTRATOR: Melinda McCracken, M.S. ------------------------------------------------------------------------------ "This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion." I. HISTORY A. WILLIAM OSLER (1918): Described obesity-hypoventilation syndrome or Pickwickian Syndrome. B. 1970's: Terms "sleep apnea" and "sleep hypopnea" coined. C. Fujita (1981): Described the UPPP D. Sullivan et al (1981): Described the use of CPAP II. DEFINITIONS A. APNEA: Cessation of airflow for at least ten seconds B. HYPOPNEA: Fall in average tidal volume by more than 50% C. CENTRAL: No airflow or respiratory effort D. OBSTRUCTIVE: No airflow despite respiratory effort E. APNEA INDEX: Apneas per hour of sleep F. SLEEP APNEA SYNDROME: Apnea index equals or exceeds 5 episodes per hour or 30 per 7 hours. III. EPIDEMIOLOGY A. Occurs almost exclusively in men (96%). B. Most are obese (70%) C. Prevalence approximately 4% of the population. D. More frequent in elderly. E. Strongly associated with snoring. IV. CLINICAL SYMPTOMATOLOGY A. Nighttime symptoms 1. Snoring: a. 100% of patients report this. b. Often best history obtained from wife. c. 68% history of snoring in late teens or twenties. d. 25% of population greater than 50 yrs. old snore. 2. Restless sleep: a. Sleepwalking b. Thrashing or gasping for air c. Choking episodes 3. Esophageal Reflux: a. Occasionally presents as dysphagia or odynophagia b. Often the patient doesn't realize he is refluxing 4. Nocturia or Nocturnal Enuresis: a. Enuresis occurs in about 5% of adults with OSA b. Nocturia with 4-7 trips to BR occurs in 28% c. Cause is sleep fragmentation,increased abdominal pressure and edema from cardiac complications. 5. Night sweats: 6. Other symptoms: a. Seizures b. Dry throat B. Daytime Symptoms 1. Excessive daytime sleepiness(EDS) a. Watching TV b. Driving 2. Byproducts of EDS a. Decreased production (job loss) b. Impaired memory and judgement c. Associated with Alzheimer's disease (1) OSA occurred in 42% of Alzheimer's patients. (2) OSA occurred in 5% of normal controls d. Dementia: Significant correlation with OSA using "Blessed Dementia Rating Scale". e. Cognitive impairment: OSA pts. found to have significantly worse scores on cognitive tests such as the Weschler Adult Intelligence Scale-Revised (WAIS-R). 3. Hypnogogic hallucinations 4. Changes in personality a. Behavior problems b. Irritability c. Aggressiveness 5. Sexual Dysfunction 6. Headaches (especially in the AM) 7. Loss of Hearing a. May be secondary to cognitive impairment b. Attention deficit V. CLINICAL EVALUATION A. Evaluation of Obesity 1. Type of obesity (Are fat folds impairing airway movement?) 2. Hx. of dieting or eating habits (May provide a clue in how to treat the patient) B. Evaluation of Oronasomaxillary Region 1. Teeth - Bite, Palate height 2. Tongue - Size and Shape 3. Soft palate - Thickness, Length, Webbing, Movement 4. Pharynx - Color, Consistancy, Lymphoid tissue 5. Nares - Septum, Turbinates, Disease process 6. Xrays and Other Exams: a. Cephalometrics: (1) Widely reported as useful in determining site of lesion. (2) Landmarks studied are Facial angle, Soft palate length, Hyoid positioning, Posterior pharyngeal distance. (3) Our study shows that only Hyoid position is statistically significant when weight is controlled for. b. CT scan and 3-d CT scan: c. Fluoroscopy: d. Rhinomanometry: Even temporary nasal obstruction can lead to apneic events and disordered sleeping. e. Pulmonary function tests: f. Fiberoptic exam: Gives one a dynamic evaluation of the upper airway system. C. Evaluation of Polycythemia (Occurs only in approx. 7%) D. Aggravating Factors 1. Very important to control or remove aggravating factors to optimize treatment. 2. Alcohol: Increases obstructive events and prolongs duration. 3. Smoking: Reported by us to increase the amount of desaturation relative to a give apnea index. 4. Sedatives: Disrupts normal sleep patterns. 5. Partial sleep deprivation: Shift work 6. Causes of temporary nasal obstruction: a. Allergies b. Trauma c. Adenoid or Tonsillar disease d. Sinusitis e. Carbon monoxide exposure E. Associated Syndromes 1. May act as presenting symptomatology. 2. May also contribute to worsen apnea or other symptomatology. 3. Again one must treat these disorders in order to optimize treatment results 4. COPD 5. Neuromuscular diseases 6. Central nervous system diseases ( May lead to central apnea) 7. Blood dyscrasias and disorders F. Risk Factors 1. Hypertension: a. 30% of essential hypertension patients have OSA. b. 55% of OSA patients have hypertension c. Treatment of OSA may cure Hypertension. d. Although male sex and obesity are common denominators chronic sympathetic hyperactivity secondary to sleep fragmentation may lead to HTN. 2. Pulmonary Hypertension: a. In both HTN and Pulmonary HTN the HTN is transient at first occurring only during the apneic events. b. HTN becomes permanent with time. c. The rapid normalization after the apneic event can lead to a relative hypotension, implicated as a cause of things such as seizure, TIA, or stroke. 3. Cardiac Arrhythmias: a. 76% of OSA patients have arrhythmias. b. 37% of these are PVCs c. Implicated as a cause of sudden death at night. d. 11% of arrhythmias are sinus arrest. 4. Heart Failure: a. Apneic events also decrease cardiac output b. This plus the above complications leads to heart failure. 5. Stroke and Anoxic Seizure 6. The above may either be contributing factors to or consequences of OSA. Sometimes breaking the cycle involves treating all components at the same time. G. Polysomnography 1. In general considered the gold standard for diagnosis of OSA. 2. With recent advances mor physiologic studies can be performed with less invasive monitoring. 3. Major Variables Studied: a. Apnea index* b. Hypopnea index* * Standard definition is number of apneic or hyponeic events per hour. We have found better correlation with desaturation values by calculating the total time per hour spent in apnea or hypopnea. This allows inclusion of average apneic or hyponeic duration in the evaluation of these patients. c. Percent of time spent in O2 desaturation. This can be expressed in bar graph form displaying the amount of time spent during sleep in each oxygen saturation value. d. The predictive value of each of these indices is not fully known. They merely provide objective measures by which the extent or presence of disease as well as response to treatment can be made. 4. Problems: a. Lack of standardization of machines b. Difficult to perform c. Interpretation may be difficult (Which variable is the most important in determining extent of disease) d. Difficult to perform and interpret in children (children with normal studies or near normal studies have died from OSA) e. Questionable correlation with symptom relief post-treatment) VI. TREATMENT: A. Medical Therapy 1. Weight control 2. Abstinence from alcohol 3. Hypertension control a. Avoid beta-blockers b. Avoid diuretics 4. Exercise - may improve pharyngeal tone 5. Discontinue of sedatives 6. Allergy therapy 7. Drug Therapy a. Thyroid hormone replacement b. Protrityline c. Medroxyprogesterone d. Almitrine e. Acetazolamide f. Nicotine B. Continuous Positive Airway Pressure: 1. Mode of Action: Splinting of the airway (Exact mode of action unknown) 2. Set Up: a. Need to acclimate pt. b. Higher settings needed to stop apnea in supine position and during REM sleep c. May need to increase pressures slowly d. Difficult to adjust alcoholic pts. 3. Rebound a. Increased REM and stage 4 NREM sleep for about a week. b. Depression of patient's arousability makes patient vulnerable to life threatening hypoxemia. 4. Decompensated Patients - should start CPAP in a hospital setting. 5. Problems a. Long term use b. Mask difficulties -> POOR COMPLIANCE c. Pressure sensation d. Nasal congestion may block effect e. Absent dentition leads to poor fit 6. Use in OSA a. Short term: Preoperatively it may be used to prove the patient's physical and cardiorespiratory status in preparation for surgery. Postoperatively it may be used to decrease risk of pulmonary edema and splint the airway until swelling resolves. b. Long term: In home use on compliant patients may stop OSA. Properly used the results are near 90 to 100%. However, there is a big problem with compliance. Beyond 6 months of therapy the compliance rate is less than 50%. This doesn't include patients who couldn't tolerate initial use. C. Surgical Therapy 1. Goals: a. Identify site of lesion b. Identify other contributing or associated factors c. Optimize the patients medical status d. Use caution in the perioperative period e. Encourage proper postoperative therapy including weight loss, alcohol rehabilitation, exercise. f. Reevaluate for other anatomical or physiological contributing factors. g. Again CPAP may play a role 2. Tracheostomy a. Mainstay of surgical therapy until 1981. b. Useful for control of airway in severe cases. 3. Uvulopalatopharyngoplasty (UPPP) a. Goal to trim the posterior margins of the soft palate and the redundant mucosa of the lateral pharyngeal wall. b. Soft palate resection stops short of the muscular portion. c. Of course attention is paid to preserve velopharyngeal competency. d. Results 40-60% success rate. e. Success rate depends upon patient selection f. Preoperative evaluation crucial. g. Sher et al. emphasize the predictive value of the Muller maneuver observed fiberoptically while the patient is supine. h. Note snoring may be eliminated and apnea still be present, so a postoperative sleep study may be useful. i. Complications: (1) Nasal Regurgitation (2) Air escape in speech (3) Nasopharyngeal stenosis - rare (4) Loss of taste 4. Tonsillectomy an Adenoidectomy a. Common in OSA in prepubertal children b. Often used as an adjunct to the UPPP 5. Nasal Surgery a. Several studies recently have shown that even temporary nasal obstruction can lead to apneic events during sleep. b. More study is necessary to determine objective indications for surgery. c. Must be evaluated for the overall care and treatment of these patients. 6. Maxillomandibular Surgery a. Several different techniques have been described. b. Goal is to advance or suspend the Hyoid and further open the airway. c. Useful in patients with a long distance between the mandibular plane and the hyoid bone. d. Also useful in retrognathia. e. Contraindications: (1) Facial angle less than 76 (2) Morbid obesity (3) Significant daytime CO2 retention 7. Anesthesia and Protection of the Airway a. Pre- and postoperative respiratory care (1) CXR and PFTs (2) Physiotherapy (3) Judicious use of bronchodialators b. Pre- and postoperative cardiac care (1) EKG (2) Control of hypertension (3) Treatment of heart failure c. Judicious use of CPAP for control of above d. Postoperative monitoring (1) Pulse oximetry (2) Intensive care setting for first 24hrs to decrease the risk of arrest, arrhythmias, pulmonary edema, airway compromise. e. Caution in the use of respiratory depressing agents. f. Anesthetic approach (1) Avoid sedative and narcotic premedication. (2) Muscle relaxants at induction should be avoided when the airway is in doubt. (3) Tracheostomy may be temporarily necessary. VII. OSA IN CHILDREN A. Presentation 1. Symptoms a. Often overlooked or not noticed by parents unless prompted. b. Mean delay for referral is approximately two years. c. Most symptoms are similar to that seen in adults. d. More common serious sequelae: (1) Developmental delay (Over 50% are less than average size for age rather than obese) (a) Failure to thrive (b) Impaired sexual maturation (c) Maxillofacial growth problems (Typically a long midface, with or without a crossbite) (d) Achondroplasia (e) Psychosocial dwarfism (2) Behavioral Disturbance (a) Poor school performance (b) Aggressive behavior (3) Corpulmonale 2. Treatment a. Tonsillectomy and adenoidectomy b. Weight reduction where indicated c. Recall need for anesthetic care Weinberg et al. - All children presenting for anesthesia for a tonsillectomy and adenoidectomy should be considered undiagnosed OSA. 3. Evaluation a. Difficult in some cases to get a good sleep study b. Children more likely to have episodic OSA with superimposed infection or allergy etc. -------------------------------END------------------------------------------- TEST QUESTIONS - The following test questions are intended to provide proof to accrediting agencies that you have read and understood the entire Grand Rounds element. Your answers should be based on the text of the Grand Rounds element. Answers should be sent by e-mail addressed to fbquinn@utmb.edu. Answers can be sent by U.S Postal Service mail, using a plain sheet of paper on which the Grand Rounds element and the subscriber are fully identified. Correct answers will be transmitted to the subscriber via e-mail. Comments and alternative points of view should be expressed at the end of the list of the subscriber's answers. The University of Texas Medical Branch (UTMB) is accredited by the Accreditation Council For Continuing Medical Education (ACCME) to sponsor continuing medical education for physicians. UTME designates this continuing medical education activity for 1 credit hour in Category 1 of the Physicians's Recognition Award of the American Medical Association. 1. Which of the following is NOT a typical complaint of a patient with obstructive sleep apnea (OSA)? a. excessive somnolence b. poor job performance c. increased appetite d. memory difficulties 2. Which of the following are significant risk factors for sleep apnea? a. young, male, obese b. older, female, thin c. older, female, obese d. older, male, obese 3. A sixty year old man complains of constant fatigue. His career is suffering from diminished job peformance. He has gained 50 lb. in weight in the past two years, which he attributes to smoking cessation. You suspect OSA. Which test would you order first ? a. CT scan of the paranasal sinuses b. MRI of the head c. polysomnogram d. chest xray 4. Which of the following define the severity of OSA? a. the lowest arterial oxygen saturation during the sleep study b. ventricular tachycardia associated with an apneic episode c. less than five respiratory events per hour d. a and b above 5. Which of the following is a treatment inappropriate for OSA? a. weight reduction b. correction of a deviation of the nasal septum c. prescriptions sedatives at bedtime d. CPAP 6. Treatment of the nasal airway intended to relieve OSA includes all of the following except a. reduction of hypertrophic nasal turbinates b. correction of an obstructing nasal septal deviation c. nocturnal sedating antihistamines d. correction of symptomatic nasal allergic disorders 7. Your first choice in treatment of OSA in a pediatric patient would be a. uvulopalatopharyngoplasty b. tonsillectomy and adenoidectomy c. laser-assisted uvulopalatoplasty d. partial resection of the base of the tongue 8. Which of the following statements about CPAP is correct? a. The principal goal is to reduce the length of the palate b. The course of treatment includes three to five sessions at four to six-week intervals c. The endpoint is reduction or elimination of snoring d. It is difficult to obtain adequate patient compliance 9. Which of the following statements concerning the postoperative period following laser-assisted uvulopalatoplasty is correct? a. Patients can experience considerable throat pain especially with eating and speaking b. A regular diet with citrus fruits and condiments is to be recommended c. Prophylactic antibiotics are mandatory for every patient. d. Steroid administration is mandatory for every patient. In order for the sponsors of this CME activity to monitor its usefulness and appropriateness to subscribers, we ask that your supply answers to the following questions concerning the accompanying Grand Rounds Online CME segment: 1. Was the presentation organized in an acceptable manner? yes no opinion no 2. Was the material adequate to your continuing education needs with respect to content? yes no opinion no 3. Was the material appropriate to your clinical practice needs? yes no opinion no 4. Did you feel that the discussants' remarks were responsive to the issues presented in the body of the Grand Rounds segment? yes no opinion no 5. Do you consider the presentation to be timely with regard to current information available in both the lay press and the professional literature? yes no opinion no 6. Are the questions submitted with the Grand Rounds element meaningful in that they stimulate thought and perhaps further inquiry? yes no opinion no 7. Is the method of submitting the subscriber's answers to these questions expeditious and convenient? yes no opinion no 8. Would you recommend this method of completing the general requirment for Continuing Education Activity to your colleagues? yes no opinion no 10. How much money (U.S. dollars) would you be willing to pay for each award of 10 or more CME Category I credits earrned through this type of online CME activity? $100 $50 $25 $12.50 $6.25 $3.00 $1.50 $0.75 $0.35 $0.15 Please submit any comments, criticisms and suggestions which you may have in the space below. They will be given thoughtful consideration, especially if they are favorable comments, gentle criticisms, or constructive suggestions. 8-) /s/ The Editor. ================================================================== Francis B. Quinn, Jr., M.D. University of Texas Medical Branch Dept. of Otolaryngology Galveston, TX 77555-0521 Internet addresses: 409-772-2706, 772-2701 fbquinn@UTMB.edu 409-772-1715 FAX fbquinn@phil.utmb.edu ==================================================================