Jargon Buster of sleep, medical & dental terms

Sleep apnoea related medical and dental jargon explained!

We provide this to remove barriers to knowledge.

Acronym What it means
AdenoidectomySurgical removal of the adenoids (small lumps of tissue located at the back of the throat, above the tonsils). Sometimes referred to as a "T and A" (meaning tonsils and adenoids) if both are to be removed.
Advanced Sleep Phase SyndromeA circadian rhythm disorder that is common in older people. The sleep phase is well ahead of conventional bedtime. Affected individuals fall asleep or wake up too early.
AerophagiaCondition of excessive air swallowing, which goes to the stomach and may cause flatulence.
AHI - Apnea-Hypopnea IndexAn index of sleep apnoea severity that combines apnoeas and hypopneas. Apneas over 10 seconds that are associated with a decrease in blood oxygenation are counted. AHI values are typically categorised as 5–15/hr = mild; 15–30/hr = moderate; and > 30/h = severe.
Ambulatory MonitoringPortable system for recording body variables during sleep.
APAPA PAP machine that automatically adjusts the pressure of the air to deliver the minimum required to overcome the apnoea. The idea is to make therapy more comfortable. Useful for patients who’s weight may vary. Also used for PAP ‘titration’
Apnea/ApnoeaWithout breath. Apnea is the US English spelling and ApnOea is the British English spelling.
Apneic episodeA period of not breathing while asleep, usually lasting for more than 10 seconds.
ArousalAn abrupt change from sleep to wakefulness - or sleep stage
AtoniaParalysed like state - no muscle tension.
BiFlex - 'Breath by breath' pressure relief. A Respironics technology that reduces the pressure of the PAP as you breathe out
BiLevelTwo different set air pressures - one for breathing IN and one for breathing OUT. More commonly used for ventilators but sometimes helpful for patients that struggle with PAP.
Biological clockA term applied to the brain process that regulates 24-hour fluctuations of body activities. It alternates sleep and wakefulness.
BiPAP AVAPS - Average Volume Assured Pressure SupportA technology that automatically adapts the delivered pressure in response to changing patient need
BiPAP® Commonly confused term with BPAP...BiPAP® is the name of a portable ventilator manufactured by Respironics Corporation.
BMI - Body Mass IndexA number that may represent how fat you are based upon a calculation from your weight and height
BPAPVariable/bilevel positive airway pressure. Often mistakenly referred to as BiPAP (a tradename of Philips Respironics) which is actually a ventilator.
BradycardiaA heart rhythm with a rate below 60 beats per minute in a human adult.
Cardiac arrestSudden absence of heart beat
CardiovascularThe heart and blood vessels
CataplexySudden onset of paralysis triggered perhaps by strong emotions such as laughter or anger. May suggest narcolepsy.
CDLNow the acronym is explained I guess its obvious...
CSACentral sleep apnoea (CSA) is a sleep-related breathing disorder in which the effort to breathe is diminished or absent. This is different from obstructive sleep apnoea (OSA) where EFFORT to breathe is made.
ChronotherapyReset of biological clock (circadian rhythm sleep disorder) by changing sleep and wake times.
Circadian rhythm sleep disorderA biological sleep/wake rhythm that does not conform to the circadian clock (24 hour light-dark cycle)
CNSThe brain and spinal cord.
Comp SAA form of sleep apnoea where central apnoeas persist or appear during attempts to treat obstructive events with CPAP
CPAP/nCPAPAlso known as fixed PAP. There is one pressure set for breathing in and out. nCPAP refers to nasal CPAP.
CPDMany professions require 'members' to keep their industry knowledge up-to-date, setting guidelines for how much development time they should complete in a year.
CSRAn abnormal crescendo / decrescendo pattern of breathing
Delayed Sleep Phase SyndromeA circadian rhythm disorder, in which the sleep phase of the sleep/wake cycle occurs after the conventional bedtime. Commonly seen as difficulty getting up in the morning.
Delta/SWSSleep stages 3 and 4 when EEG delta waves are most often seen.
DiaphragmThe large muscle attached to the rib cage at bottom of the chest. Breathing in (inhalation) occurs when the diaphragm contracts.
DxA medical professional’s identification of the nature, cause and severity of your medical condition
ECG/EKG - ElectrocardiographyRecording the electrical activity of your heart
EEGRecording brain electrical activity through sensors on the scalp
EMG - ElectromyographyRecording the electrical activity of your muscles
ENTSurgery on the soft tissue at the back of your mouth (soft palate and/or pharyngeal walls). Sometimes known as Otolaryngology
Enuresis - nocturnalPersistent, involuntary, night time bed-wetting.
EOG - Electro-oculogramRecording of eye movements during sleep. Rapid eye movements signify REM sleep. EOG may be recorded in sleep studies.
EPAPExpiratory (breathing-out) pressure setting for a PAP machine
EpochA short period of time (usually 20-60 seconds) of the sleep recording.
EPR - Expiratory Pressure ReliefReduction of air pressure when the patient breathes out
Esophageal Pressure(US spelling of oesophageal). A measurement that may be used to determine breathing effort and calculate airway resistance.
ESS -Epworth Sleepiness Scale/Epworth Score/EpworthA scale intended to measure daytime sleepiness by use of a very short questionnaire. This may be helpful in diagnosing sleep disorders. It asks the individual to rate their probability of falling asleep on a scale of increasing probability from 0 to 3 for eight different situations. The scores for the eight questions are added together to obtain a single number. A number in the 0–9 range is considered to be normal while a number in the 10–24 range indicates that expert medical advice should be sought.
Evidence based medicineWikipedia defines evidence based medicine as "the conscientious, explicit and judicious use of current best evidence in making decisions about the care of individual patients"
Excision/exciseTo cut off/cut out completely
GERD/GORDAcid reflux. When stomach acid comes up the throat. It may occur at night and disrupt sleep.
Habitual snorerSomeone who snores nearly every night.
Health related quality of lifeSimple assessments of physical abilities by an external rater ( see SF36 on this link) Wikipedia link to Quality of Life
HistogramA graphical representation of the distribution of data - usually referring to a sleep study output.
HypercapniaAn increased amount of carbon dioxide, the waste product of respiration, in the blood.
HypersomnolenceTechnical expression for excessive daytime sleepiness.
Hypnic jerkSensation of "jerking" awake just as you fall asleep. Quite normal and experienced by many people.
HypnogramThe final printout of the all-night sleep stages(REM and non-REM) after an overnight study.
HypopneaEpisodes of 'under breathing' . Not considered as severe as apnoea however, it may be associated with a blood oxygen level drop and/or fragment sleep.
HypothyroidismAlso known as myxedema (mix-si-dee-ma). When the thyroid gland fails to make enough thyroid hormone. Can present as obstructive sleep apnoea.
HypoventilationInadequate breathing. Too shallow or too slow, which doesnt meet the needs of your body. If you hypoventilate, your body's carbon dioxide level rises, which then results in too little oxygen in your blood.
Hypoxia/HypoxicA condition in which your body as a whole or a region of your body (tissue hypoxia) is deprived of an adequate oxygen supply
InsomniaDifficulty in either getting to sleep or maintaining sleep
InvasiveA medical procedure where the skin must be penetrated
IPAPPressure setting of air for inspiration (breathing in) on a PAP machine
Jet lagFatigue, sleep and impaired alertness due to a large and rapid change to a new time zone.
LAUPLaser assisted uvulopalatoplasty - laser scarring of the soft palate that causes scarring which in turn stiffens the soft palate
MacroglossiaLarge tongue
ManometerDevice to measure the pressure being deliv-ered by a CPAP machine (usually measured in centimeters of water [cm H2O]); a common CPAP pressure is about 10).
Maxillo-facialThe jaws and face
Microarousalsery brief “awakenings,” perhaps seen only when the brain waves are being monitored via encephalography
Mixed sleep apnoeaBoth central and obstructive apnoea.
MMOASurgical operation to move both jaws. Option of last resort for patients who have not responded to CPAP and uvulopalatopharyngoplasty (UPPP) surgery.
Movement arousalsShort awakenings with minor body movements, about which the sleeper is unaware.
MRDMandibular means lower jaw and repositioning means holding the jaw in a different place. Sometimes repositioning is changed to advancement and/or device is changed to splint or appliance (MAS, MAD or MAA) and they may also be known as an Oral Appliances….
MRD/MRA/MASA small, generally plastic device worn in your mouth at night to hold the lower jaw forwards. (See MRD)
NarcolepsyA cause of daytime sleepiness resulting from 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 CannulaA thin hollow tube that fits behind the ears with a set of two prongs which are placed up the nostrils. Used to measure the airflow as you breathe in (inspiration) and out (expiration)
Night TerrorsAn incomplete arousal from slow wave sleep that is usually confined to children. If woken up there is often no recall of why they were so scared.
Nocturia/NocturesisFrequent need to urinate during the night
Non-invasiveMedical procedure not penetrating the skin or a body cavity
NREM SleepNon REM sleep - stages 1 through 4.
Obesity-Hypoventilation SyndromeA term for obese people who have unusally slow and shallow breathing (hypoventilation) while awake that results in an increased level of carbon dioxide in their blood.
Oesophageal(British spelling of esophageal). A measurement that may be used to determine breathing effort and calculate airway resistance.
Oral appliancesA device worn in your mouth to hold the lower jaw forward and away from the back of the throat. This mechanical 'protrusion' may open the airway behind the tongue.
OSA/OSASRepeated breathing interruptions during sleep, which despite the effort to breathe, are usually associated with a reduction in blood oxygen saturation. Obstructive = a blockage or restricted airway. The pauses in breathing are called “apnoeas” and typically last 20 to 60 seconds. OSAS is when these sleep disturbances result in daytime sleepiness.
OsteotomyA surgical operation where a bone is cut.
OximetryContinuous monitoring of oxygen saturation of arterial blood from a pulse oximeter; the sensor is usually attached to the finger
Oxygen DesaturationLess than the normal amount of oxygen in the blood. A value below 90% is thought abnormal.
Oxygen SaturationHow much oxygen is in your blood. Normally this ranges from 90% to 100%. This is an important indicator of sleep disordered breathing.
PAPPneumatic splinting of the airway through delivery of a stream pressured air. It is the main stay therapy for obstructive sleep apnoea. Air is pushed from a flow generator through tubing and a mask which is worn over your nose/face. The air then passes through up your nose and into your throat, where the pressure keeps the upper airway open. A humidifier may also sometimes be added to moisten the air to relieve nasal irritation or dryness.
PAPSTAir pressure delivered spontaneously i.e. when the patient demands it. Timed - delivers air pressure at set time intervals regardless of the patient demand.
ParasomniaA movement event occurring while asleep or made worse by sleep. Eg: sleepwalking
Patient Reported Outcomes Measurement Information SystemA measure of health status (physical, mental, and social well–being) from the patients perspective.
PCP - Primary Care PhysicianGeneral Medical Practitioner or commonly known as your family Doctor
PharyngealPharynx or back of the throat
PharynxThe area behind the nose and mouth.
Polysomnographic TechnologistHealth care professional trained in performing diagnostic sleep studies - see PSG.
Prescribed CPAP PressureThe pressure/settings that are determined by a CPAP titration sleep study, that are prescribed for your CPAP therapy machine
PSGOvernight sleep study. Multiple recordings are made including EEG, EOG, EMG (the three basic stage scoring parameters), EKG, respiratory air flow, respiratory excursion, lower limb movement
Pulse-OximeterNon-invasive measurement of oxygen saturation in the blood. Normal ranges are between 95-100%.
Quality of life - QoLThis is the general well-being of the individual or society (see HRQoL)
Radiofrequency AblationRadiofrequency (RF) Procedure (also known as Somnoplasty) - procedure for treating nasal obstruction, snoring and in some cases, sleep apnoea. The procedure uses radiowave energy to reduce snoring and the size of the soft palate.
RDIA number that includes all sleep related respiratory events per hour
REM motor atoniaParalysis of muscles during REM sleep - so you don't 'act out' your dreams.
REM sleepRapid eye movement sleep - sleep characterized by the active brain waves, flitting motions of the eyes, and weakness of the muscles; most dreaming occurs in this stage, which accounts for about 20% of sleep in adults.
REM Sleep Behaviour DisorderWhen REM sleep motor atonia (paralysed like state) is partially or completely missing.
Restless Legs SyndromeA sleep disorder characterised by 'tingling' type sensation in the legs that happens when you are not moving. Tremendous need to move the legs which relieves the sensations - but limits sleep.
ScreeningPreliminary assessment of your snoring to determine the presence, absence and severity of sleep apnoea. Typically carried out using a pulse-oximeter with a nasal canula to determine the air flow from your nose
Sedentary occupationA job that does not require much movement. For example a truck driver, pilot, office worker.....
SeptoplastySurgery on the nasal septum (the partition that divides the nasal passage)
SerotoninA chemical in your brain that regulates sleep and other functions.
SDBIs the term for patterns of abnormal breathing while asleep.
Sleep apnoeaRepeated breathing interruptions during sleep, which despite the effort to breathe, are usually associated with a reduction in blood oxygen saturation. Obstructive = a blockage or restricted airway. The pauses in breathing are called “apnoeas” and typically last 20 to 60 seconds.
Sleep architectureThe sequence, length and stage during a sleep period. Often displayed in the form of a histogram.
Sleep cycleThe regular change between NREM and REM sleep - one cycle consists of a NREM period and one REM period.
Sleep debtThe result of long term sleep deprivation - when you do not sleep sufficiently. Similar to a financial debt in that it has to be repaid.
Sleep efficiencyThe number of minutes of sleep divided by the number of minutes you spent in bed. Normally this is approximately 85 to 90% or higher. Same as sleep quality.
Sleep fragmentationBrief awakenings throughout the night, that reduce the total amount of restorative/deeper sleep. Sleep fragmentation may lead to sleep deprivation.
Sleep Fragmentation Brief arousals occurring throughout the night, reducing the total amount of time spent in the deeper levels of sleep
Sleep hygieneWays to behave that promote continuous and good quality sleep
Sleep inertiaFeeling 'rough'/sleepy on waking that persists for up to 20 minutes.
Sleep latencyHow long it takes you to go to sleep - from when you decide to go to sleep.
Sleep Log A daily, written diary of your sleep-wake times. Should also include use of medicines and consumption of caffeine drinks - and how you feel on waking.
Sleep qualityA measure of how well you slept calculated by dividingin the number of minutes of sleep by the number of minutes you spent in bed. Normally this is approximately 85 to 90% or higher. Same as sleep efficiency.
Sleep talkingTalking while asleep may occur during REM sleep. The sleeper is not fully awake and has no memory of talking. Almost certainly nonsense!
Sleep walkingSleep walking - somnambulists may do very complex acts, such as dusting or going to the toilet and even arguably driving.
SnoringNoisy breathing while asleep. Perhaps a warning sign of sleep apnoea.
SnoreplastyAn injection of a chemical into the soft palate to stiffen it through the creation of scar tissue.
SomnoplastyTrade name for radio-frequency ablation
SpO2The amount of oxygen in the blood. Normally about 95-100%
SRBDThe collective term for an abnormal respiratory [breathing] pattern.
Stop-BangA paper assessment that may help you to determine if you are at High or Low risk of Sleep Apnea. You should then consider sleep apnoea screening
SymptomaticMeans showing symptoms. Symptoms are signs of disease or injury.
Type 2 Diabetes MellitusType 2 diabestes is a metabolic disorder that is characterised by hyperglycemia (high blood sugar) in the context of insulin resistance and a relative lack of insulin.
Tachycardia A fast or irregular heart rate
TiControlA technology from ResMed used to synchronise the delivered the pressure from the PAP machine with the patient's breath.
TitrationAdjustment of the therapy performed by a medical/dental professional to suit the patient’s needs. Alternatively, in the context of PAP automatic adjustment of the pressure to establish the minimum effective treatment pressure
TMDJaw joint ache/pain.
TMJThe jaw joint
TonsillectomySurgical removal of the tonsils (a mass of lymphatic tissue at the throat).
Tonsillectomy Surgical removal of the tonsils
ToothgrindingGrinding your teeth while asleep. May occur in approximately 70% of people.
TracheostomySurgery to open in the throat (trachea). Absolutely the last option for severe obstructive sleep apnoea as it bypasses an obstruction in the airway
Transient ArousalsBriefly waking up from sleep - probably with no awareness of having done so.
TRDA type of sleep oral appliance that holds the tongue forwards.
TSTThe actual sleep time in a sleep episode. Total sleep time is the total of all REM and NREM sleep.
TSTTotal Sleep Time
TTTThe duration of the sleep study (measured by how long the machine was turned on)
TurbinateBone shelf (shaped like an elongated sea-shell) that protrudes into the breathing passage of your nose
UARS In between snoring and sleep apnoea. Repeated increases in resistance to airflow that lead to brief arousals and daytime sleepiness. Apneas and hypopneas may be totally absent. Blood oxygen levels can be in the normal range.
UvPPP, UPPP, U V 'triple' PSurgery on the soft palate and pharyngeal walls
UvulaDangly bit at the back of the throat
VentilatorAny machine designed to mechanically move breatheable air into and out of the lungs
VPAPA specialised PAP machine designed specifically for central sleep apnoea (CSA) in all its forms, including complex, mixed sleep apnoea and Cheyne-Stokes respiration
Vsync™A ResMed technology that compensates for detected air leaks from the PAP mask.
VTThe amount of air that passes in and out of your lungs in an ordinary breath in litres.
ZeitgeberGerman word for "time giver" that has become more widely used in sleep medicine. A cue from your environment to your biological clock, such as light, food, temperature.