What is obstructive sleep apnea?Obstructive sleep apnea (OSA) is a disorder caused by the repetitive collapse of the upper airway during sleep. It is the
- loud snoring
- interruptions in breathing while sleeping
- morning headaches
- feeling disgruntled or grumpy
- repetitive awakenings throughout the night
What causes obstructive sleep apnea?The following are some conditions associated with OSA:
- obesity hypoventilation syndrome, a breathing disorder in people with obesity
- endocrine conditions, such as hypothyroidism, acromegaly, and polycystic ovary syndrome, which may affect your breathing when you’re asleep
- chronic lung disease, such as asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis
- neuromuscular conditions, such as a stroke, which can interfere with brain signals to your chest muscles and airway
- heart or kidney failure, which may cause fluid to build up in your neck and obstruct the upper airway
Risk factorsThe risk for OSA increases if you have physical features that narrow your upper airway. Risk factors of OSA include:
- large tonsils
- men with a collar size of 17 inches or more
- women with a collar size of 16 inches or more
- a large tongue, which can block the airway
- retrognathia, which is when your lower jaw is shorter than your upper jaw
- a narrow palate or airway that collapses more easily
- family history of OSA
How is obstructive sleep apnea diagnosed?A diagnosis of sleep apnea begins with a complete history and physical examination. A history of daytime sleepiness and snoring are important clues. Your doctor will examine your head and neck to identify any physical factors that are associated with sleep apnea. Your doctor may ask you to fill out a questionnaire about daytime drowsiness, sleep habits, and quality of sleep. In some cases, the evaluation for OSA may be performed at home without a technician in attendance. However, home sleep apnea testing is only useful for the diagnosis of OSA in certain people. It is not a substitute for other diagnostic tests if other sleep disorders are suspected. The following tests may be performed to diagnose OSA.
During a polysomnography, you sleep overnight in a hospital or sleep center while connected to a variety of monitoring devices that record physiologic variables.
Patterns of physiologic abnormalities during sleep may indicate sleep-disordered breathing as well as many other sleep disorders.
While you sleep, the PSG will measure the activity of different organ systems associated with sleep. It may include:
- electroencephalogram (EEG), which measures brain waves
- electrooculogram (EOM), which measures eye movement
- electromyography (EMG), which measures muscle activity
- electrocardiogram (ECG), which measures heart rate and rhythm
- pulse oximetry test, which measures changes in your oxygen levels in your blood
EEG and EOMDuring an EEG, electrodes are attached to your scalp that will monitor brain waves before, during, and after sleep. The EOM records eye movement. A small electrode is placed 1 centimeter above the outer upper corner of your right eye, and another is placed 1 centimeter below the outer lower corner of your left eye. When your eyes move away from the center, this movement is recorded. Brain waves and eye movements tell doctors about the timing of the different phases of sleep. The two broad phases of sleep are non-REM (non-rapid eye movement) and REM (rapid eye movement). Decreased muscle tone and paralysis occur during REM sleep.
EMGDuring an EMG, two electrodes are placed on your chin: one above your jawline and the other below it. Other electrodes are placed on each shin. The EMG electrodes pick up the electrical activity generated during muscle movements. Muscle relaxation should occur during sleep. The EMG picks up when your muscles relax and move while you’re sleeping.
ECGA single lead ECG records the electrical signals from your heart during the sleep study to monitor your heart rate and rhythm.
Pulse oximetryIn this test, a device called a pulse oximeter is clipped onto a thin area of your body that has good blood flow, such as a fingertip or earlobe. The pulse oximeter uses a tiny emitter with red and infrared LEDs to measure the oxygen saturation level of your blood. This level may decrease during episodes of apnea.
Treatment optionsThe goal for the treatment of OSA is to make sure airflow isn’t obstructed during sleep. Treatment methods include the following:
Weight lossWeight management and exercise are usually recommended for people with OSA who also have obesity. Although it may not lead to complete remission, weight loss
Continuous positive airway pressure (CPAP)Continuous positive airway pressure (CPAP) therapy is the first line of treatment for OSA. It is administered through a face mask worn at night. The face mask gently delivers positive airflow to keep the airways open at night. The positive airflow props the airways open. CPAP is a highly effective treatment for OSA. For people with mild or moderate OSA who don’t benefit from CPAP therapy, an oral appliance is a reasonable alternative to positive airway pressure.
Bilevel positive airway pressure (BPAP)Bilevel positive airway pressure (BPAP) machines are sometimes used for the treatment of OSA if CPAP therapy is not effective. BPAP machines, sometimes called BiPAP machines, have settings that deliver two pressures in response to your breathing: inhaled pressure and exhaled pressure. This means the pressure changes during inhaling versus exhaling.
Sleeping on your sideSince sleeping on your back (supine position) can make OSA worse for some people, positional therapy is used to help you learn to sleep on your side.
SurgeryThere is no consensus regarding the role of surgery in adult patients with OSA. In general, you may consider surgical therapy when CPAP or BPAP machines or an oral appliance aren’t effective. Surgical treatment may be the most effective for people who have OSA due to a severe, surgically correctable, obstructing lesion of the upper airway. Being a surgical candidate depends on factors such as:
- your desire to have surgery
- if you have a surgically correctable problem
- your overall health to undergo surgery