Obstructive sleep apnea (OSA) describes a medical condition that is characterized by intermittent
episodes of absence of breathing (apnea) caused by complete obstruction of the upper airway passages during sleep. Narrowing of the air passages at the back of the throat occur in certain group of individuals.
Complete closure of these passages can occur during sleep as a result of further relaxation of the tissue at
the back of the throat.
During these episodes of apnea, which last from 10-90 seconds, reduction of oxygen level in the body develops until the apnea is terminated by an arousal, which restores the airway patency. This cycle of events is repeated multiple times during sleep in individuals with OSA, resulting in fragmented sleep.
- How common is this condition?
- What are the consequences of OSA?
- When do we suspect OSA?
- How is OSA diagnosed?
- What is a sleep study?
- Can OSA be treated?
OSA is an under-recognized and under-diagnosed condition worldwide. It is estimated that OSA affects up to 25% of the adult population. A study showed that 93% of women and 82% of men with moderate to severe OSA are not diagnosed.
What are the consequences of OSA?
Excessive daytime sleepiness is a major consequence of OSA. It can result in:
- Poor concentration and memory
- Affect job and school performance
- Affect relationships
- Poor quality of life
- Increased risk of motor vehicle accidents
- Hypertension
- Heart failure and heart attacks
- Heart rhythm, abnormalities
- Strokes
- Increased lung pressures (pulmonary hypertension)
- Death
When do we suspect OSA?
We suspect OSA in individuals with the following symptoms:
- Excessive daytime sleepiness
- Gasping and choking during sleep
- Poor concentration at work or school
- Loud habitual snoring
- Hypertension
How is OSA diagnosed?
OSA is suspected based on symptoms and physical examination. The diagnosis of OSA is confirmed further by a sleep study (polysomnography) that is interpreted by a sleep physician.
What is a sleep study?
It is a multiple-component test that electronically transmits and records specific physical activities while an individual sleeps. The recordings become data that are analyzed by a qualified physician to determine whether or not a sleep disorder is present, including OSA. OSA is diagnosed when there are more than 5 episodes of apnea lasting at least 10 seconds in one minute during the entire sleep period.
The equipments used in a sleep test include:
- Surface electrodes on the face and scalp that will send recorded electrical signals from the brain, eyes and muscles to the measuring equipment
- Belts placed around the chest and abdomen to measure breathing frequency
- ECG (electrocardiogram) to record heart rate and rhythm
- Sensor at the nostrils to record airflow
- Bandage-like probe on the finger to measure the amount of oxygen in the body
- Microphone to record snoring activity
The sleep study is done overnight and it can be done in hospital or home setting. Qualified sleep technicians will be involved in setting up the equipments.
The sleep physician upon completion of the sleep study will prepare a detailed report. It provides useful diagnostic information about sleep related breathing disorders, movement disorders in sleep and other less common conditions like seizures in sleep and other abnormal behaviours during sleep.
Can OSA be treated?
Treatment of OSA is based on severity of OSA and individualized approach. Mild OSA can be treated with weight loss, better sleep hygiene, sleep posture, reducing alcohol consumption and dental devices.
The most effective treatment will be the use of continuous positive airway pressure (CPAP) machine where air pressure is used to keep the upper airway passages continuously open during sleep. Removing the obstruction will improve the sleep and reverse the hypertension, cardiac problems and metabolic abnormalities associated with OSA.
Occasionally, surgery involving the upper airway and jaw may be indicated in certain individuals.
For Appointments, pls call: +65 6311 4710
No comments:
Post a Comment