Welcome to The Sleep Apnoea Trust Association

Working to improve the lives of sleep apnoea patients,their partners and their families. Managed by volunteers, SATA is regarded as the leading UK charity working in the field of Sleep Apnoea

Complimentary Medical Alert card and purchase of a Medical Equipment Baggage Tag are now additional benefits if you join the Trust


Sleep Apnoea – Glossary of Terms

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

A

ACROMEGALY

A curious condition of increased growth hormone production in adults that can present as an obstructive sleep apnoea.

ALCOHOL

Alcohol relaxes the throat muscles and may provoke snoring and obstructive apnoea.

ANAESTHESIA

A potentially dangerous time for people with sleep apnoea. The anaesthetic drugs, pre-medication sedatives and post operative pain relief drugs can all worsen sleep apnoea.

APNOEA

A pause in breathing; conventionally more than 10 seconds. From the Greek a (without) pnoea (breath).

APNOEA HYPOPNOEA INDEX (AHI)

The ApneaHypopnoea Index or ApnoeaHypopnoea Index (AHI) is an index used to indicate the severity of sleep apnoea. It is represented by the number of apnoea and hypopnoea events per hour of sleep. The apnoeas (pauses in breathing) must last for at least 10 seconds and be associated with a decrease in blood oxygenation.

AUTO CPAP MACHINE (APAP)

A clever computerised CPAP machine that adjusts its pressure automatically to match the minimum pressure required to keep the airway open. It works very well for some people, though others find the small delay in reaching the right pressure troublesome

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B

BARIATRIC SURGERY

An important way for patients with a BMI 35 and above who have not responded to other measures, to lose weight rapidly by keyhole surgical intervention. There are four main types of operations, gastric banding, gastric bypass, sleeve gastrectomy and duodenal switch.

BECONASE

Nasal steroid spray. Extremely useful to reduce nasal inflammation and swelling. Can be used for long periods. Can be obtained over the counter without prescription or online. Flixonase is very similar but is prescription only.

BILEVEL POSITIVE AIRWAY PRESSURE (BiPAP)

BiPAP is a form of breathing assistance using a ventilator device that delivers extra air pressure into the airway via a mask placed on the face. The level of air pressure provided varies on breathing in or breathing out. BiPAP can also be set to deliver a breath if there has not been a breath within a certain number of seconds. It is used for patients who are under-breathing for a number of conditions, including COPD, kyphoscoliosos and respiratory muscle weakness.

BODY MASS INDEX (BMI)

Body Mass Index (BMI) is an indication of a healthy body in relation to weight. A healthy BMI is between 19 and 25, 25-30 is overweight, 30-35 is obese and over 35 morbidly obese. Being overweight is a common risk factor for OSA.

BUBBLE CPAP

With the combined effects of Optimal Humidity and natural pressure oscillations, bubble CPAP provides a protective, safe and effective method of respiratory support to spontaneously breathing neonates.

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C

CATAPLEXY

Sudden loss of muscle power, with collapse onto the ground, but no loss of consciousness. A feature of narcolepsy that occurs particularly during moments of excitement or anticipation.

CENTRAL SLEEP APNOEA (CSA)

Episodes of stopping breathing, not due to obstruction of the upper airway, but due to the brain simply failing to ask for a breath. Much less common than obstructive sleep apnoea. Treatment tends to focus on treating the underlying cause if this can be identified, for example, heart failure.

CHEYNE-STOKES-BREATHING

Breathing that cycles up and down, also know as periodic breathing. Found in people with heart failure and neurological problems.

CHIN SUPPORT / STRAP

A strap or loop of material passing under the chin, sometimes needed to hold the mouth closed to prevent air leaks during nasal CPAP or nasal ventilation.

CHRONIC BRONCHITIS

Airway narrowing usually caused by smoking. Other names are chronic obstructive pulmonary disease and emphysema.

CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)

Airway narrowing usually caused by smoking. Other names are chronic bronchitis and emphysema.

CONTINUOUS POSITIVE AIRWAY PRESSURE (CPAP)

The process of delivering a continuously raised airway pressure from a small electric pump, via a mask on or under the nose or over the nose and mouth.

CYANOSIS

The bluey colour one goes when low in oxygen.

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Common Medical Abbreviations

Common Medical Abbreviations Associated With Sleep Apnoea

Common Medical Abbreviations

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D

DENTAL DEVICE

see Mandibular Advancement Device.

DESATURATIONS (SEE ALSO HYPOXIC DIPS)

The falls in oxygen levels, seen on the oximeter, that usually accompany apnoeas. Also known as desaturations, because when it is not hypoxic the blood is described as fully saturated with oxygen.

DIAPHRAGM

Main muscle of breathing between the bottom of the chest and stomach; pulls the lungs out, thus drawing in air.

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E

EAR PLUGS

Foam earplugs, the most comfortable available, but not quite as good as cotton covered wax ones. They are little foam cylinders that are rolled up into a thin core which then slowly expands after insertion into the ear canal. Like all earplugs, they take two or three nights to get used to. Available from most chemists or online

ELECTRO-ENCEPHALOGRAM or EEG

EEG, most people only use the abbreviation. Recording of brain waves, required for sleep staging.

ELECTRO-MYOGRAM (EMG)

Recording of muscle activity. Used as part of sleep staging.

ELECTRO-OCULOGRAM (EOG)

Recording of eye movements, required for sleep staging to define rapid eye movement sleep (or dreaming sleep).

EMPHYSEMA

Airway narrowing usually caused by smoking. Other names are chronic bronchitis and chronic obstructive pulmonary disease (COPD).

EPWORTH SLEEPINESS SCALE (ESS)

Eight questions asking about tendency to drop off at inappropriate times, used to gauge how sleepy someone is. A score of 0-10 is normal, 11-15 possibility of mild to moderate OSA and 16 and over, severe OSA or narcolepsy.

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F

FLIXONASE

see Beconase

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H

HUMIDIFIER

A CPAP Heated Humidifier houses a water chamber, which it heats to moisturise the air provided by your machine. They are ideal for those who find the machine leaves them waking with a dry mouth, sore nasal passages or simply find the air cold and therefore uncomfortable. Also assists asthmatics during periods of high pollen count.

HYPERCAPNIA

A raised level of carbon dioxide in the blood. This is the gas normally breathed out which will rise if breathing is inadequate. It may be measured by taking an arterial or capillary blood sample.

HYPERSOMNOLENCE

Technical expression for excessive sleepiness.

HYPNOGRAM

The final print out of all the night sleep stages (REM and non-REM).

HYPOALLERGENIC

Materials that cause a lower allergy reaction, e.g CPAP filters and hay fever or asthma

HYPOPNOEA

A period of underbreathing, conventionally for more than 10 seconds.

HYPOTHRYOIDISM

Also known as myxoedema when extreme. When the thyroid gland fails to make enough thyroid hormone. Can present as obstructive sleep apnoea and snoring.

HYPOXIA

When the body is short of oxygen and therefore the level in the blood falls.

HYPOXIC DIPS

The falls in oxygen levels, seen on the oximeter, that usually accompany apnoeas. Also know as desaturations, because when it is not hypoxic the blood is described as fully saturated with oxygen.

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I

INSOMNIA

Being awake when you want to be asleep. Often thought of as a problem,but may not be. Common if people try to spend too long in bed.

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L

LASER

Used by surgeons as an alternative to a scalpel. Cuts and coagulates vessels (lessens bleeding) at the same time.

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M

MANDIBULAR ADVANCEMENT DEVICE (MAD)

Intra-oral device worn at night to hold the mouth closed and the lower jaw forward. Increases the space behind the tongue, which lessens snoring and may help obstructive sleep apnoea. Obtained from dentists.

MANOMETER

Device to measure the pressure being delivered by a CPAP machine (usually measured in centimetres of water {cmH20} – where a common CPAP pressure is about 10).

MICRO AROUSALS

Very brief “awakenings” or lightening of sleep, perhaps only seen when the brain waves (EEG) are being monitored.

MOVEMENT AROUSAL

These are short awakenings with minor body movements of which the sleeper is unaware.

MUFFLES

Wax ear plugs. Less comfortable than the foam ones but more effective. From most chemists.

MULTIPLE SLEEP LATENCY TEST (MSLT)

MSLT is a sleep disorder diagnostic tool. It is used to measure the time elapsed from the start of a daytime nap period to the first signs of sleep, called sleep latency. The test is based on the idea that the sleepier people are, the faster they will fall asleep.

MULTIPLE WAKEFULNESS TEST (MWT)

MWT is used to measure how alert you are during the day. It shows whether or not you are able to stay awake for a defined period of time. This is an indicator of how well you are able to function and remain alert in quiet times of inactivity.

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N

NARCOLEPSY

A cause of daytime sleepiness due to an inherited disorder of the control of dreaming sleep. Has to be differentiated from sleep apnoea, periodic leg movements and other rarer causes of daytime sleepiness.

NASAL CPAP

The process of delivering a continuously raised airway pressure via a mask on the nose. 

NASAL CPAP SYSTEM

Mask – Consisting of three main types, nasal pillows, nasal mask and full face mask

Nasal Pillows – sits under the nose with short pillow protrusions into the nasal passages, that inflate slightly due to the slight increase in air pressure once the pump starts

Nasal Mask – fits over the nose on a cushion, that is sealed by the slight increase in air pressure once the pump starts

Full Face Mask – Covers the nose and mouth on a cushion that is sealed by the slight increase in air pressure once the pump starts.

Pump or blower – main unit developing the pressure. Ramp – the slow rise to full pressure after first turning on the machine, available from some manufacturers.

NASAL INTERMITTENT POSITIVE PRESSURE VENTILATION (NIPPV)

The same as BiPAP (this is a brand name like Hoover).

NECK CIRCUMFERENCE

One of the best predictors of whether there are upper airway problems during sleep. More than 16″ – could be a snorer, more than 17″ could have sleep apnoea. One can still have sleep apnoea with smaller necks but it is less common.

NEONATES

Baby less than a month old.

NICE

The National Institute for Health and Care Excellence (NICE) provides national guidance and advice to improve health and social care. For OSA there are two references of importance on their website

CPAP on the NHS-TA139

Management of OSAS – CKS

NOCTURIA

Excessive urine production at night. Seen in sleep apnoea quite often.

NOCTURNAL HYPOVENTILATION

Underbreathing at night.

NON REM SLEEP

See sleep stages.

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O

OBSTRUCTIVE SLEEP APNOEA (OSA)

A relatively common condition where the walls of the throat relax and narrow during sleep, interrupting normal breathing. This may lead to regularly interrupted sleep, which can have a big impact on quality of life and increases the risk of developing certain conditions.

OBSTRUCTIVE SLEEP APNOEA SYNDROME (OSAS)

Obstructive sleep apnoea syndrome defines patients with repetitive apnoeas and symptoms of sleep fragmentation with excessive sleepiness (BTS definition)

ORLISTAT

Weight loss tablets that can be obtained over the counter without prescription or online, but care is needed.

OSA 50

A self assessment questionnaire that helps to identify how likely you are to have OSA.

OTRIVINE

Nasal spray to reduce congestion. Can only be used for up to five nights consecutively: therefore of most use during a cold. Can be obtained over the counter without prescription or online..

OXIMETER

Monitoring device that continuously measures the level of oxygen (oxygen saturation) in the blood by measuring its colour: usually done with a clothes peg like clip on the finger or ear. A common way to analyse the overnight tracing is to count the number of dips in oxygen.

OXYGEN DESATURATION INDEX (ODI)

The oxygen desaturation index (ODI) is the number of times per hour of sleep that the blood’s oxygen level dropS by a certain degree from baseline. The ODI is typically measured as part of standard sleep studies, such as a diagnostic polysomnogram, home sleep apnea testing, or with overnight oximetry.

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P

PALATE

The soft tissue flap that hangs down the back of the throat attached to the roof of the mouth. The tip is also called the uvula. The whole structure is often called the soft palate to differentiate it from the roof of the mouth (a bony structure), also called the hard palate.

PANIC AROUSALS

Episodes of awaking with sensation of panic. Sometimes due to bad dreams and stress, or as a consequence of waking and sensing the upper airway is blocked.

PERIODIC LIMB MOVEMENT SYNDROME (PMLS)

A condition where the legs move every 40 seconds or so, producing brief arousals. Another cause of daytime sleepiness. Sometimes associated with Restless Legs symptoms. Distinct from myoclonus (an involuntary muscle jerk experienced by many people as they drop off to sleep. by many

PHARYNX

Essentially the throat area between the voice box and the back of the nose behind the tongue. A floppy muscular tube.

PICKWICKIAN SYNDROME

An old term for large people with problems of underbreathing, beautifully described by Charles Dickens. Included a lot of diagnosis. No longer used by those that know!

POLYSOMNOGRAPHY

Simply means a recording of lots of things during sleep. Has come to mean recording at least EEG, EMG and EDG all night.

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R

RAINOUT

Rainout is where there is a collection of condensed water in the tube from a CPAP machine to the mask and it is pushed through to the mask by the airflow, splashing cold water on the nose or face of the patient. It generally only occurs with patients using humidifiers, where the damp air comes into contact with the cold surface of the tube in a cold bedroom and condenses. Patients can place the tube under the bed cover, fit a tube cover or get an electrically heated tube to mitigate rainout.

REM SLEEP

See sleep stages.

RESTLESS LEG SYNDROME

Also known as PLMS and nocturnal myoclonus. An uncomfortable creepy-crawly sensation of the legs and an irresistible urge to move them, experienced mostly in the evening and at night. Another cause of daytime sleepiness.

RINATEC

Nasal spray that reduces congestion and discharge. Can be used on a long term basis. Can be obtained over the counter without prescription or online.

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S

SCOLIOSIS

A twisting of the spine that can limit lung expansion and lead to problems of underbreathing, which can be alleviated by overnight breathing support.

SLEEP STAGES

Sleep is conventionally divided into five stages. Four of these are called non-REM sleep, the other is REM (or Rapid Eye Movement) sleep. REM sleep is when we dream, and the brain is virtually awake. Non_REM sleep is graded 1 to 4 and represents increasing depths of sleep. This is the sleep required to refresh, with the two deeper stages 3 and 4 called slow wave sleep.

SLOW WAVE SLEEP

See sleep stages

SNORING AROUSALS

Sleep can be disturbed not only by actual episodes of stopping breathing, but also by snoring alone (when a big increase in breathing effort is required to overcome the narrowing of the upper airway that led to the snoring).

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T

TONSILS

Collection of tissues involved in fighting infection on the side walls of the throat, which usually melt away by the age of 8 or so, but may persist and partly block the pharynx or throat.

TRACHEOSTOMY

Creating a hole into the windpipe from outside, just below the Adam’s apple. Sometimes needed when patients in intensive care are on a ventilator for a prolonged period, or following surgery for head or neck cancer. It used to be the main treatment for obstructive sleep apnoea (opened at night, closed during the day) to bypass the obstruction in the throat.

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U

UPPER AIRWAY RESISTANCE SYNDROME

A term for significant snoring with sleep arousals/very mild obstructive sleep apnoea. Used to describe the relationship between upper airway narrowing during sleep, sleep disruption, and the daytime consequences of excessive sleepiness.

UVULOPALATOPHARYNGOPLASTY

Don’t bother with the pronunciation – say UPPP or U-triple P instead! The operation that cuts away part of the soft palate and side wall of the pharynx (or throat) in an attempt to reduce snoring volumes. Not very effective and extremely painful.

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X

XENICAL

Weight loss tablets that can be obtained over the counter without prescription or online, but care needed.

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