Information to support you

A glossary of terms

Terms that you’ll come across on your sleep apnea* journey

Glossary

Apnea (obstructive)

When the soft tissue in your airway collapses for ten seconds or more while you sleep. During an apnea, air is not able to reach your lungs and the carbon dioxide levels in your blood rise.

Apnea (central)

When your brain does not tell you to breathe for ten seconds or more while you sleep. During this time, air is not able to reach your lungs and the carbon dioxide levels in your blood rise.

Apnea-Hypopnea Index (AHI)

Number of apneas you have in one hour of sleep. Normal: 0-4, Mild sleep apnea: 5-14, Moderate sleep apnea: 15-29, Severe sleep apnea: 30 or more.

ASV device

Used to treat a more complicated, central sleep apneas, the ASV provides variable pressures througout the night in order to deliver an effective treatment.

Auto device

Auto therapy devices sense your needs and provide variable pressures throughout the night.

Compliant

If you are using PAP therapy for four hours or more a night, for 70% of nights then you are considered to be benefiting from treatment. Great work!

Continuous Positive Airway Pressure (CPAP)

The same level of gentle pressurised air is delivered to your airway whether you are breathing in or breathing out.

Cheyne–Stokes respiration (CSR)

When breathing becomes increasingly deeper then shallower with possible periods of apnea. This cycle can range from 30 seconds to two minutes. Also known as periodic respiration.

Device

This is the machine that is delivering your prescribed pressure therapy.

Filter (grey)

Stops dust from entering your PAP device and should be washed in warm water once every two weeks.

Filter (white)

Prevents pollen from entering your PAP device and is useful if you are particularly sensitive to pollen or dust particles. Do not wash this filter. Order a new one every 12 months.

GP

Your local doctor or General Practitioner can refer you to a sleep specialist, or answer any questions that you have about your condition.

Humidifier

A box containing water that connects to your PAP device and adds moisture to the air being delivered. The humidifier can improve comfort by helping to reduce some of the common side effects of PAP therapy, such as nasal irritation and upper airway dryness.

Hypopnoea

Similar to an apnea but your airway only partially narrows. This still causes shallow breathing and reduces the amount of air that can reach your lungs.

International Standard of Compliance

Sleep clinicians around the world believe that people need to use PAP therapy for four hours or more a night to receive the full health benefits of treatment.

Leak

Although it’s important for carbon dioxide to escape through your mask’s exhalation port, unintentional air leak around the edge of the mask can make PAP therapy unpleasant. Unintentional leak can be avoided by spending time fitting and adjusting your mask well. The mask and headgear should not be over tightened.

Modem

A small black box that plugs into the back of your device, which collects data and sends it to your sleep specialist. They are then able to monitor your sleep patterns and effectiveness of treatment.

Non-compliant

Unfortunately, according to the International Standard of Compliance, you are not using your PAP device for long enough to fully benefit from therapy. Please don’t worry, we’re here to help you succeed – make sure that you contact your sleep specialist to discuss any difficulties you may be experiencing.

Ramp button

Button on the top of your PAP device which allows you to fall asleep more comfortably. When pressed, it reduces the air pressure, gradually increasing it over time until your prescribed setting is reached. The ramp button can be pressed if you wake up in the night and find it difficult to fall back to sleep. In the early days of therapy, you may need to use the ramp button several times a night.

Sleep specialist

Also known as your consultant, sleep specialists manage your therapy and ensure that you are benefitting from treatment. They can answer any of your questions, give professional advice and are happy to help you when needed.

*Also known in the UK as ‘Apnoea’