Sleep Apnea

Do you think you might have sleep apnea? Take our online quiz "Am I At Risk" and find out.

Normal breathing results from nerve signals being sent to the diaphragm, chest wall and throat, telling them when to contract and when to relax. When the muscles contract, the diaphragm pulls down expanding the lung space to draw in air and the throat muscles hold the airway open for air to enter. When the muscles relax, the lungs return to normal size and push out the excess air. We can control our breathing a little when we are awake, but most people can't hold their breath for much longer than about a minute before they are gasping for air. When we are asleep, breathing is automatic, regulated by the midbrain in response to carbon dioxide and oxygen levels in the blood.

Apnea means absence of breath. There can be various reasons why a person may stop breathing in their sleep.

Obstructive Sleep Apnea (often just called sleep apnea, or sometimes OSA) occurs when the airway collapses during sleep and, although the person is making an effort to breath, the airway is blocked and breathing is prevented. see SDA fact sheet - Sleep Apnea

Central Sleep Apnea (or CSA) is due to disruption of the brain signals, and there is no effort to breathe. see SDA fact sheet - Central Sleep Apnea

Continuous Positive Airway Pressure (or CPAP) is used to treat OSA, and may sometimes be effective in CSA. This is a machine that produces air at a high enough pressure to hold the airways open. There are fixed pressure CPAP machines, and automatic machines that adjust the pressure upwards only when you stop breathing. Some models allow completely different pressures for inhaling and exhaling (BiPAP). see SDA fact sheet - CPAP

Oral Appliances (also known as Mandibular Advancement Devices) may be helpful for people who have problems using CPAP. If OSA is caused primarily by a narrowed airway, these devices can be worn like a mouthguard, and position the lower jaw slightly forward, to increase space in the throat. see SDA fact Sheet - Oral Appliances

Things to Avoid. There are things that can make sleep apnea worse, and even if you are on CPAP treatment, they should be avoided. Alcohol relaxes muscles and may worsen apnea, as may sleeping tablets which depress the drive to breathe. A person’s normal CPAP pressure may be insufficient if the person is under the effects of alcohol or sleeping tablets. Other things that disrupt sleep such as caffeine or late night eating should also be avoided.