Clinical Considerations for
Obstructive Sleep Apnea Syndrome
by Charles J. Curatalo, MD
Neurologist, neurophysiologist, and sleep medicine specialist at Santa Barbara Neuroscience Institute at Cottage Health System
Usually associated with a drop in blood oxygen saturation, obstructive sleep apnea syndrome (OSAS) reduces the quality of sleep, causes daytime tiredness and has other potential medical consequences.
Most people with obstructive sleep apnea syndrome (OSAS) are not aware of the disorder and primary care physicians cannot detect it
during a routine office visit. If OSAS is suspected, a primary care physician should ask the patient— and family member or bed partner, if available— the following questions:
If affirmative answers are given to any of these questions, consider further evaluation for a possible underlying sleep disorder.
An estimated 12 million Americans suffer from OSAS, a sleep disorder caused by the repetitive partial or complete collapse of the upper airway during sleep, resulting in a physical block to airflow despite respiratory effort. OSAS is most common in middle-aged, overweight males; women are more likely to develop OSAS after menopause. Risk factors include excess weight, large neck circumference (more than 17 inches in men or 16 inches in women), advancing age, nasopharyngeal abnormalities that reduce the caliber of the upper airway, use of alcohol or sedatives, cigarette smoking, and certain underlying medical conditions such as hypothyroidism or acromegaly.
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Signs and Symptoms of OSAS
Indications of OSAS can include loud snoring, excessive daytime sleepiness, witnessed breathing pauses during sleep, nocturia or enuresis, morning headaches, dry mouth or sore throat upon waking, sleep fragmentation, sudden arousals from sleep with a feeling of choking or gasping, sexual dysfunction and poor concentration. Reduced work performance, depression, anxiety or irritability may also be reported.
Untreated OSAS has been associated with hypertension, heart failure, myocardial infarction, atrial fibrillation, sudden cardiac death, stroke, work-related or driving accidents, diabetes, glaucoma, headaches and difficulty controlling
Sleep is divided into two types: rapid eye movement (REM) and non-rapid eye movement (NREM).
The American Academy of Sleep Medicine further divides NREM into three distinct stages: N1, N2 and N3. Deep sleep occurs in stage N3.
A sleep study conducted by a sleep lab is typically required for accurate diagnosis of OSAS . Modern, fully-equipped sleep labs are available at Santa Barbara Sleep Clinic in Goleta and SleepMed of Santa Barbara, located adjacent to Santa Barbara Cottage Hospital. Board-certified physician sleep specialists supervise and interpret the studies, while certified respiratory technicians perform the studies, set up treatment, monitor patients and coordinate follow-up care.
Weight loss for overweight patients can potentially be curative and is strongly recommended. For some, not sleeping in the supine position, using a positional sleeping device, and avoiding alcohol and sedatives in the evening can be beneficial. Use of dental appliances—which pull the tongue or mandible forward to open the upper airway during sleep—can be helpful for some.
The most effective treatment for moderate to severe OSAS is continuous positive airway pressure (CPAP ) treatment using a nasal mask that applies a positive pressure “splint” to the upper airway to allow normal breathing during sleep. Modern CPAP machines are small, quiet and convenient for travel. Various mask arrangements are available for improved patient comfort. Follow-up contact with a respiratory therapist and sleep specialist to ensure proper mask fit and equipment operation significantly improves long-term compliance and treatment effectiveness.
Surgical treatment for OSAS is sometimes an option and can be curative. Various procedures are used, depending on the specific clinical circumstances. In children or adolescents with OSAS and adenotonsillar hypertrophy, surgery is the treatment of choice.
Patients with significant sleep apnea report feeling dramatically better very quickly after utilizing CPAP or another effective treatment. Outcomes include much-improved sleep quality, better daytime functioning and reduced risk of medical consequences.
Case Study: Obstructive Sleep Apnea Syndrome
A 60-year-old male with a history of hypertension, gastroesophageal reflux disease (GERD) and paroxysmal atrial fibrillation was referred by his cardiologist for a sleep study. The patient was overweight and had gained 20 pounds in the preceding three years. Symptoms included witnessed apneic events, nocturia, dry mouth and not feeling rested in the morning, even after eight or nine hours of sleep. Physical examination revealed a low-hanging palate, long uvula and narrow oropharyngeal aperture.
All-Night Sleep Study Results
An in-lab, technician-attended polysomnogram showed reduced sleep efficiency of 70 percent at baseline. Loud snoring, no REM sleep and reduced non-REM deep sleep (stage N3) were achieved. Severe obstructive sleep apnea syndrome (OSAS) was documented with a respiratory disturbance index (RDI) of 80 apneas/hour supine and 33/hour on his side. The longest apneic event was 44 seconds in duration, the lowest oxygen saturation was 77 percent, and occasional bradytachyarrhythmia was noted in association with apneic events.
After three hours of sleep, a continuous positive airway pressure (CPAP) titration was performed with a nasal mask and heated humidifier. With CPAP at an optimum pressure of 8cm H2O, sleep efficiency improved to 89 percent, snoring and all apneic events were eliminated, and sleep architecture showed a rebound in REM and stage N3 sleep. The patient reported feeling more rested and alert in the morning after 4.25 hours of CPAP use.
CPAP Treatment Results
The patient reports continued excellent clinical benefit after using CPAP treatment at home for 18 months. In addition to more restful, less fragmented sleep, nocturia episodes were reduced to one or none per night, daytime sleepiness and snoring were eliminated, and he has experienced no further episodes of atrial fibrillation.
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The patient’s sleep study hypnogram demonstrates the elimination of apneic events and oxygen desaturations with some REM sleep rebound following initiation of CPAP at 1:30 a.m.
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