Obstructive Sleep Apnea
Definition of Obstructive Sleep Apnea (OSA)
As taken from the National Sleep Foundation, obstructive sleep apnea is a sleep disorder in which breathing is briefly and repeatedly interrupted during sleep. The "apnea" in sleep apnea refers to a breathing pause that lasts at least ten seconds. Obstructive sleep apnea occurs when the muscles in the back of the throat fail to keep the airway open, despite efforts to breathe. Another form of sleep apnea is central sleep apnea, in which the brain fails to properly control breathing during sleep. Obstructive sleep apnea is far more common than central sleep apnea.
Obstructive sleep apnea, or simply sleep apnea, can cause fragmented sleep and low blood oxygen levels. For people with sleep apnea, the combination of disturbed sleep and oxygen starvation may lead to hypertension, heart disease and mood and memory problems. Sleep apnea also increases the risk of drowsy driving.
Anesthesia Concerns
Obstructive sleep apnea is a concern for patients undergoing anesthesia. People with OSA have increased risk of morbidity and mortality during surgery. At Stony Brook Medicine we take special care to identify patients with obstructive sleep apnea. We also take action to ensure that all necessary supports are in place for our OSA patients. This allows us to create the safest possible surgical experience for them.
During your pre-operative visit you will be asked to complete a questionnaire to aide us in assessing your sleep apnea status. Patients who are identified as having OSA, even if they have not been formally diagnosed, will have safety measures put in place and be advised to follow up for OSA evaluation and treatment.
Prevalence
Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder. As reviewed from Up To Date.com, in North America ~ 20-30% of males and ~ 10-15% of females meet criteria for obstructive sleep apnea. Those numbers can change based on the criteria utilized to define OSA. It is felt that the rates of OSA in America are rising due to rising rates of obesity. The presence of OSA also varies by race and ethnicity. African Americans younger than 35 have higher rates of OSA when compared to Caucasians of the same age group independent of body weight. The rates of OSA in Asia are similar to that in America despite lower rates of obesity. It is felt that these differences may be related to craniofacial anatomical differences.
Risk Factors
Anyone can develop obstructive sleep apnea. However, certain factors put you at increased risk, including:
- Being overweight. Around half of people with obstructive sleep apnea are overweight. Fat deposits around the upper airway may obstruct breathing. Also, people with obstructive sleep apnea tend to have a larger waist.
However, not everyone with obstructive sleep apnea is overweight and vice versa. Thin people can develop the disorder, too.
- Having a large neck. The size of your neck may indicate whether you have an increased risk. A thick neck may narrow the airway and may be an indication of excess weight. A neck circumference greater than 17 inches for men and 16 inches for women is associated with an increased risk of obstructive sleep apnea.
- Having high blood pressure (hypertension). Obstructive sleep apnea is relatively common in people with hypertension.
- Having a narrowed airway. You may inherit a naturally narrow throat. Or your tonsils or adenoids may become enlarged, which can block your airway.
- Having chronic nasal congestion. Obstructive sleep apnea occurs twice as often in those who have consistent nasal congestion at night, regardless of the cause. This may be due to narrowed airways.
- Having diabetes. Obstructive sleep apnea may be more common in people with diabetes.
- Being male. In general, men are twice as likely to have obstructive sleep apnea.
- Being African American. Among people under age 35, obstructive sleep apnea is more common in African Americans.
- Being a certain age. Obstructive sleep apnea usually occurs in adults who are ages 18 to 60, but it can occur at any age.
- Having a family history of sleep apnea. If you have family members with obstructive sleep apnea, you may be at increased risk.
- Smoking. People who smoke are more likely to have obstructive sleep apnea.
- Using alcohol. Alcohol may worsen obstructive sleep apnea.
Symptoms
Signs and symptoms of obstructive sleep apnea include:
- Excessive daytime sleepiness
- Loud snoring
- Observed episodes of breathing cessation during sleep
- Abrupt awakenings accompanied by shortness of breath
- Awakening with a dry mouth or sore throat
- Awakening with chest pain
- Morning headache
- Difficulty concentrating during the day
- Experiencing mood changes, such as depression or irritability
- Difficulty staying asleep (insomnia)
- Having high blood pressure
How do I find out if I have it?
Discussion with your primary care physician is the best place to start. During that visit, you can expect your doctor to perform a physical exam. During that exam evaluation of airway and measurements of your neck and abdomen may be taken. Your doctor may have you complete a questionnaire or ask you questions related to your sleep habits to determine if you are at risk. If concern for OSA exists after initial evaluation you may be referred to a sleep specialist who can perform specialized testing that will diagnose OSA. Your doctor also may refer you to an ear, nose and throat doctor to rule out any anatomic blockage in your nose or throat.
A sleep specialist may conduct additional evaluations to diagnose your condition, determine the severity of your condition and plan your treatment. The evaluation may involve overnight monitoring of your breathing and other body functions as you sleep. Tests to detect obstructive sleep apnea include:
- Polysomnography. During this sleep study, you're hooked up to equipment that monitors your heart, lung and brain activity, breathing patterns, arm and leg movements, and blood oxygen levels while you sleep. You may have a full-night study, in which you're monitored all night, or a split-night sleep study.
In a split-night sleep study, you'll be monitored during the first half of the night. If you're diagnosed with obstructive sleep apnea, staff may wake you and give you continuous positive airway pressure for the second half of the night.
This test can help your doctor diagnose obstructive sleep apnea and adjust positive airway pressure therapy, if appropriate. This sleep study can also help rule out other sleep disorders, such as periodic limb movements of sleep or narcolepsy, which also can cause excessive daytime sleepiness, but require different treatment.
- Oximetry. This test monitors and records your blood oxygen level while you're asleep and can be used a screening test for obstructive sleep apnea. If you have obstructive sleep apnea, the results of this test will often show drops in your blood oxygen level during apneas and subsequent rises with awakenings.
If the study reveals temporary drops in oxygen compatible with obstructive sleep apnea, a polysomnogram may follow to formally diagnose obstructive sleep apnea and determine appropriate therapy.
- Portable monitoring. Under certain circumstances, your doctor may provide you with an at-home version of polysomnography to diagnose obstructive sleep apnea. This test usually involves measurement of airflow, breathing patterns and blood oxygen levels.
What are the treatments for Obstructive Sleep Apnea?
Positive Airway Pressure Devices
Positive airway pressure machines, used with a variety of breathing masks, are the most widely used treatment for moderate and severe sleep apnea. They have been endorsed by the American Academy of Sleep Medicine.
The mask, worn snugly over the nose, or sometimes nose and mouth, during sleep, supplies pressurized air that flows continuously or intermittently into the sleeper's throat. The increased air pressure prevents the sleeper's airway from collapsing.
Although PAP devices are not used to treat snoring alone, they do eliminate snoring in addition to treating obstructive sleep apnea.
Oral Appliances
Oral appliances look like the mouth guards worn by football players. The oral appliances for treating sleep apnea and snoring are specially designed for that purpose.
The appliance is worn in the mouth during sleep. Most appliances work by positioning the lower jaw slightly forward of its usual rest position. This small change is, in many people, enough to keep the airway open during sleep.
Upper Airway Stimulation Devices
Inspire Upper Airway Stimulation (UAS) Therapy
http://stonybrookmedicine.edu/patientcare/sleepdisorders
http://www.nlm.nih.gov/medlineplus/ency/article/000811.htm
http://www.nhlbi.nih.gov/health/health-topics/topics/sleepapnea/treatment