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A Comprehensive Glossary of Sleep Apnea Terms

 

By Admin

 

If you’ve been a sleep apnea patient for some time, you may be familiar with the many terms used to describe the disorder’s symptoms, tests, and treatment parameters. But for those who are new to treatment or recently diagnosed, there is a lot to become familiarized with. In the interest of keeping our readers informed and providing easy-access information, we have organized a comprehensive list of relevant terms with thorough and clearly stated explanations. Links to additional resources are also included for further reading. If you have any questions about these terms or any others, feel free to contact us live on our website via chat, or by email at [email protected].  

 

Adaptive Servo-Ventilation (ASV):  Adaptive servo-ventilation is an advanced form of positive airway pressure (PAP) therapy that makes automatic pressure adjustments in real time to match patient breathing patterns. Adaptive servo-ventilation is ideal for central breathing disorders that involve apnea events or other complications not caused by obstruction. These breathing problems, such as Cheyne–Stokes Respiration (CSR), benefit from the breath-by-breath adjustments of ASV systems.   

Anti-Asphyxia Valve (AAV):  The anti-asphyxia valve (AAV) is a safety feature on some PAP therapy masks that allows the patient to breathe air from outside the mask in the case of a power failure or other complications. The AAV allows patients to avoid breathing recirculated air when a PAP therapy device is not working correctly. 

Auto CPAP (APAP):  Auto CPAP, AutoPAP, or APAP for short, means automatic positive airway pressure. This type of PAP therapy device is able to automatically switch between pressure settings throughout the night. While Adapto-Servo Ventilation (ASV) tends to have a higher range of adjustments, APAP uses two settings. One setting is for higher pressure needs, such as an apnea events, and lower setting is the minimum pressure setting for the patient. By contrast, a standard CPAP device uses one constant pressure setting throughout therapy. APAP is also referred to as auto-titrating positive-airway pressure, or AutoSet for the ResMed product line.  

Apnea:  An apnea event consists of partial or complete cessation of breathing, defined as a 90 percent or greater reduction in baseline breathing rate. When this occurs, the person suffering from the apnea event will not receive oxygen for periods of time, often causing desaturation and/or excess carbon dioxide buildup to occur. The word apnea means “without breath,” and refers to periodic episodes that can last up to several minutes at a time.

Apnea Event:  Apnea event is the term used to describe occurrences of apneas during the night. An Apnea event is defined in the same way that apneas are, by high-percentage reductions from baseline breathing rates. See: Apnea  

Apnea–Hypopnea Index (AHI):  The Apnea-hypopnea index, or AHI, is a record of the number of apneas or hypopneas a patient has during a sleep session. AHI information is displayed as a measurement of blockages (hypopneas) and apnea events during an average hour of sleep. Individual AHI ratings are determined using the AHI severity index.  

AHI Severity Index:  The AHI severity index determines the rating for individual sleep apnea conditions. Using the parameters below, the AHI system defines each level of intensity according to the average number of events per hour of sleep. Normal 0-5 events/hour Mild 5-15 events/hour Moderate 15-30 events/hour Severe 30+ events/hour These parameters represent the standards of the industry. While each PAP therapy device may have its own method of displaying AHI information, the terms, acronyms, and levels of intensity will be the same for all available models. .  

BiPAP/BiLevel Therapy:  BiLevel therapy, also called variable level therapy (VPAP) uses different pressure levels for inhalation and exhalation. Usually, a higher pressure level is used for inhalation and a lower level for exhalation. While standard CPAP therapy delivers air in one fixed pressure level, some patients find the pressure difficult to breathe into when exhaling. Therefore, a BiLevel Pressure Therapy is designed to create a more comfortable therapy experience by maximizing pressure needs during exhalation only.  

Blood Oxygen Saturation:  Blood oxygen saturation is the level of oxygen-saturated hemoglobin in the blood. The human body requires a strict balance of oxygen in the blood to function normally, between 95 and 100 percent. If the oxygen saturation level falls below 90 percent, hypoxemia can develop. If it falls below 80 percent, tissues and organs may not receive the oxygen needed to continue functioning, which can cause permanent damage to vital organs such as the brain and heart  

Body Mass Index (BMI):  Body mass index (BMI) is a measurement of body mass according to height. Determined by squaring body height and dividing the weight by the result, BMI is meant to represent average healthy weight ratios for size, allowing people to assess whether they are of healthy weight, overweight, or underweight for their height. It is expressed in units of kg/m2, resulting from mass in kilograms and height in metres (squared).  

Central Breathing Disorders:  Central breathing disorders is the blanket term for any breathing disorders caused by brain signals or other problems not related to physical obstructions. For example, central sleep apnea and Cheyne-Stokes respiration both occur when the body’s automatic act of breathing stops for other reasons even when the airway is open.  

Central Sleep Apnea:  Central Sleep Apnea (CSA) is a type of sleep apnea involving breathing stops when airways are not blocked. This type of sleep apnea is the result of problems associated with the autonomic function of breathing. Thus, the automatic signals sent from the brain to regulate breathing become interrupted during sleep. Central sleep apnea is sometimes combined with obstructive sleep apnea, which is known as mixed or complex apnea.  

Cheyne–Stokes Respiration (CSR):  Cheyne-Stokes respiration is a form of central breathing disorder that results in rough or rapid breathing, often at night during sleep. Cheyne-Stokes respiration is characterized by moments of deepening breaths that release and cause lapses in breathing before recovering. Also called Cheynes-Stokes breathing, this disorder is very specific in its patterns, known as cycles of apnea and hyperpnea.  

Climate Control:  Climate Control refers to humidification technology used by some PAP therapy devices, such as the ResMed product line. Climate Control gives users easy access to humidification settings to ensure the most comfortable temperatures and protect the mask from rainout. Settings can be manual as well as automated, and may require specific S9™ therapy device, an H5i™ heated humidifier and a ClimateLine heated tube.  

CO2 Wash-Out:  CO2 Wash-Out is when a mask is emptied of excess CO2 that has remained during exhalation. All masks must have a way to wash out CO2 in order to prevent the wearer from continually re-breathing exhalations.  

Comorbidity:  A comorbidity is another health condition that coexists with a primary condition under scrutiny. In other words, Comorbidities are any other health conditions simultaneously affecting the patient, either related or non-related. Comorbidities can also by mental or behavioral disorders.  

Complex (Mixed) Sleep Apnea:  Complex sleep apnea, or CompSA for short, is a type of mixed sleep apnea involving both obstructive and central sleep apnea events. In most cases of complex sleep apnea, the central apnea events occur when attempting to treat obstructive sleep apnea events. In some cases, patients with complex sleep apnea will switch from standard CPAP therapy to a BiLevel or BiPAP therapy device, which uses two pressure settings, to treat the persistent apneas. See also: Obstructive Sleep Apnea; Central Sleep Apnea; BiLevel Therapy  

Compliance:  Compliance is the term for proper adherence to a doctor's recommendations. It is often used to describe a patient’s therapy habits and whether or not they follow the recommended schedule for best results. Compliance for PAP therapy can be measured by the number of therapy hours per night. For example, some insurance companies define compliance as a minimum average of four hours per night for at least 70 percent of the nights measured. Health insurance reimbursements for PAP therapy equipment often have similar requirements.  

Conducted Noise:  Conducted noise is a term referring to the sound emitted by PAP therapy systems. Also called radiated noise, conducted noise is sometimes heard from the tubing or the device itself. Most conducted noise is minimal for modern PAP therapy masks and machines. See also: Radiated Noise. 

Chronic Obstructive Pulmonary Disease (COPD):  Chronic obstructive pulmonary disease (COPD) is a lung disease caused by pollutants and other irritants in the air. Often developing over time as a patient remains exposed to the cause, COPD can block airflow and make it difficult to breathe. COPD is often caused by cigarette smoking, air pollution, or dust.  

Continuous Positive Airway Pressure (CPAP):  Continuous Positive Airway Pressure (CPAP) is the term used to describe standard PAP therapy systems that emit constant pressure at a single setting. CPAP uses pressurized air through a hose and mask system to prevent the airway from collapsing during sleep. The pressure setting is determined by the patient (or the patient’s apnea-hypopnea index (AHI)), and is normally adjusted during initial setup. This is known as titration, and it is recommended that a doctor or CPAP specialist chooses the setting to match the patient’s breathing. Most CPAP machines have pressure settings from 4 cm H2O to 20 cm H2O.  

CPAP Mask:  CPAP masks are used with CPAP machines and CPAP tubing to deliver air pressure to a patient’s airway. There are many different CPAP mask types that include full-face masks, nasal masks, and nasal pillow masks. The type of mask preferred often depends on the breathing and sleeping style of the patient. For example, a person who often breathes through the mouth may want a full-face mask, while a person who feels uncomfortable or claustrophobic with large mask on may prefer a nasal option. Some patients try a few different styles before making a permanent selection.  

Durable Medical Equipment Provider:  A durable medical equipment (DME) provider is a company or retailer that specializes in medical equipment that is meant to last. This includes medical devices such as CPAP machines and accessories.  

Easy-Breathe Technology:  Easy-Breathe technology is the name of ResMed’s air delivery system, which includes an Easy-Breathe motor to reduce sound.  

Electroencephalograph (EEG):  An EEG is a machine that records electrical activity in the brain. Using electrodes placed on the head, the EEG reads the different types of waves that characterize each sleep stage. As each type of brain wave has a specific frequency, and each sleep stage includes a specific pattern of wave forms. Note: EEG can also refer to an electroencephalogram, which is a reading by an electroencephalograph.  

Exhalation Relief:  Exhalation relief is the term used to describe the lowering of air pressure during exhalation. While this feature is associated with BiLevel machines, some CPAP devices also include it as an option. Exhalation relief is a comfort feature that allows patients to breathe out without having to breathe against a high pressure level. See also: Expiratory Pressure Relief (EPR)  

Expiratory Pressure Relief (EPR):  Expiratory Pressure Relief (EPR) is ResMed’s version of exhalation relief. EPR on ResMed devices can decrease air pressure at three different levels when the patient exhales. Level 1 is the lowest amount of exhalation relief and level 3 is the highest.  

Flow:  Flow is a short term for airflow on a PAP therapy system. Specifically, it refers to the air entering the mask and flowing into the lungs when a patient breathes. On some devices the flow can shift between different pressure levels during therapy.  

Flow Limitation:  Flow limitation refers to restrictions in the airway. Limitations to flow occur when the airway is obstructed, or when some other event reduces the airflow.  

Full-Face Mask:  Full-face masks are a type of PAP therapy mask that covers the mouth as well as the nostrils. Full-face masks are good for mouth breathers or for those who prefer a sturdy system to stay in place when they move during sleep. See also: Nasal Pillow Masks; Nasal Masks  

Home Sleep Test (HST):  A home sleep test is a sleep assessment that monitors a patient’s patterns from their own bed at home. A number of different assessment tools are used to determine sleep conditions and patterns, most using sensors that can read vital signs and other physiological data.  

Humidification/Humidifier:  For PAP therapy systems, humidification is used to provide more comfortable therapy experiences and reduce irritation that may occur from the airflow. Humidifiers keep the airflow warm and moist as it enters the tubing and mask, helping many sleep apnea patients sleep more comfortably and soundly. Humidification can greatly improve the therapy experience. See also: Climate Control  

Hypopnea:  A hypopnea is a moment of extremely shallow breathing caused by obstruction or other problems. Often accompanied by low respiratory rates, a hypopnea event is normally characterized by gradual changes that worsen over time, such as during sleep. By definition, a hypopnea involves a breathing reduction by 50% for 10 seconds or longer.  

Hyperpnea:  Hyperpneas are increases in the depth and rate of breathing, often during sleep. The cause of hyperpneas may be physiologic—such as when the body needs to compensate to meet the metabolic demand of body tissues in repair, or it may be pathologic. Whereas hypopneas involve shallow breathing, hyperpneas involve faster rates and deeper breaths.  

Hypoxemia:  Hypoxemia is low blood oxygen saturation. It is caused by all forms of sleep apnea, as the reduction normal breathing patterns reduces the amount of oxygen entering the body. The body depends on oxygen from the blood to fuel the organs and tissues. This is also called tissue hypoxemia, and can result in serious complications. Symptoms of Hypoxemia include shortness of breath, rapid heart rate, and respiratory difficulties.  

Insomnia:  Insomnia is the inability to sleep normally. Those with insomnia have difficulty falling asleep, staying asleep, or feel tired when they awake as if they had not slept through the night. Insomnia is the most prevalent sleep disorder and the only sleep disorder more common than sleep apnea. It is commonly associated with other disorders as well, and in some cases can result in serious health issues as the body’s need for sleep is continually denied.  

Inspiration:  Inspiration is the term for breathing inward or inhaling. Expiration, or exhalation, is the term for breathing outward. Breathing is both an automatic and non-automatic process which can be altered with conscious effort, but still continues when the conscious efforts end. Breathing with the help of a device is known as mechanical breathing. See also: Exhalation 

Inspiration Pressure:  Inspiration pressure is the pressure delivered by a PAP therapy device during inward breaths. In some PAP therapy devices, this pressure level differs from the Expiration pressure, which can lower to make outward breaths more comfortable. See also: Inspiration; Exhalation Relief  

Inspiration Time (Ti):  Inspiration time is the length of time, measured in seconds, that a patient spends on a single inhalation during PAP therapy. This can be an average inhalation time, or a single inhalation time. See also: TiControl  

Invasive Ventilation/Invasive Therapy:  Invasive Ventilation/Invasive Therapy is a method of ventilation therapy that requires a component inside the body to provide the ventilation. The opposite is Non-Invasive Ventilation (NIV), which does not require the insertion of a component such as tube into the throat (intubation), or via an incision in the throat called a tracheotomy. PAP therapy is considered non-invasive ventilation because it does not require anything to enter the patient’s body to provide air. See also: Tracheotomy; Non-Invasive Ventilation (NIV)  

Intelligent Volume-Assured Pressure Support (iVAPS):  Intelligent Volume-Assured Pressure Support (iVAPS) is a volume assurance mode found in some of ResMed’s ventilators. iVAPS monitors airflow to determine how much is needed at any given time. See also: Volume; Pressure  

Leak:  Leaking occurs when PAP therapy masks lose air not intentionally emitted. For example, air may be lost at the seal if it is not properly set against the patient’s face or nasals. While exhalation ports are meant to diffuse exhaled carbon dioxide, too much air lost at the mask seal can disrupt the system. While some leakage is to be expected, it should be minimal. At times, heavy mouth breathing can cause leakage problems as well. Leak is measured on PAP systems, and Total Leak is the term used to describe the combined air loss including exhalations.  

Lower Airway:  The lower airway includes the organs in the body that aid in respiration. This includes the windpipe and lungs, as well as the lower larynx below the vocal folds. . See also: Upper Airway 

Minute Ventilation:  Respiratory minute ventilation is the volume of air breathed in or out within a 60-second period. This includes the total of both the inspiration and expiration during the 60-seconds. It is part of the ventilatory rate, and an important measure of respiration. See also: Tidal Volume    

Mixed Sleep Apnea:  A mixed sleep apnea, also called a complex sleep apnea, is a combination of obstructive and central sleep apnea events. Often this occurs when there is both a blockage and a central breathing issue disrupting respiration messages from the brain. See also: Complex Sleep Apnea  

Mouth Leak:  Mouth leak refers to the air that escapes through the mouth when using nasal positive airway pressure. Mouth leak is always a possibility when using a mask other than a full-face model, but it many cases it does not disrupt therapy.

Multiple Sleep Latency Test (MSLT):  A Multiple Sleep Latency Test (MSLT) is a study that measures rates of sleep latency during day hours. These tests are often used to detect narcolepsy. See also: Narcolepsy  

Narcolepsy:  Narcolepsy is a disorder that involves excessive sleepiness during the day. Severe cases can lead to loss of consciousness at any time, even during dangerous activities such as driving a car or operating heavy equipment. Narcolepsy usually begins in adolescence and continues into late adulthood.  

Nasal Mask:  A nasal mask is a type of PAP therapy mask that uses nasal attachments rather than a full-face mask to deliver airflow. Nasal masks cover only the nose, and leave room for speech or other activities. Nasal masks are often preferred by those who feel overburdened or claustrophobic using full-face models. . See also: Nasal Pillow Mask; Full-Face Mask  

Nasal Pillow Mask:  Nasal pillow masks are a type of PAP therapy mask that are similar to standard nasal masks, but use nasal cushions (pillows) as nasal seals. used during positive airway pressure (PAP) therapy. The nasal pillows rest at the entrance to the nose, gently sealing in the nostrils. These masks are minimalistic and less obtrusive than nasal or full face masks. See also: Nasal Mask; Full-Face Mask  

Noninvasive Ventilation (NIV):  Noninvasive ventilation (NIV) is a way to deliver airflow to a patient without inserting anything into the body, including devices, drugs, or surgery. NIV uses pressurized air through tubes and masks to deliver airflow. See also: Invasive Ventilation  

Non-REM Sleep:  Non-REM sleep refers to the stages of sleep when rapid eye movement (REM) does not occur. REM normally occurs during the fourth stage of sleep, often called the REM sleep stage, while stages one through three rarely exhibit any REM behavior. See also: REM sleep  

Obstructive Sleep Apnea (OSA):  Obstructive sleep apnea (OSA) is the most common of the sleep apnea types, accounting for up to a billion individuals worldwide. Obstructive sleep apnea results from blockages in the airway, usually caused by partial or total collapse of the tissues during sleep. OSA is extremely prevalent in the U.S., though increased awareness and better treatments are helping people to sleep better and reverse the damage caused by low oxygen levels in the blood (See Hypoxemia). OSA is linked to many other health risks. See also: Apnea; Central Sleep Apnea; Complex Sleep Apnea; Comorbidity  

Oximeter:  An oximeter is a small device that clips onto a patient’s fingertip to read pulse rates and oxygen saturation. Oximeters use tiny sensors, often accompanied with a home sleep test (HST) device, for an assessment of sleeping patterns and behaviors that provide a complete sleep-health profile. See also: Pulse Rate; Home Sleep Test (HST)  

Oxygen Therapy:  Oxygen therapy is a term for any device that delivers oxygen to a patient, usually through a tube to the patient’s airway to aid in breathing, or to breathe for the patient entirely.  

Positive Airway Pressure (PAP) Therapy:  PAP therapy is the general blanket term for all forms of positive airway pressure therapy, including CPAP, APAP, BiPAP, and ASV. PAP therapy uses airflow to keep the airway open during sleep, giving patients a chance to sleep without disruptions from apnea events. It is by far the most popular form of sleep apnea treatment, and is advancing rapidly as a technology.  

Periodic Breathing:  Periodic breathing is a type of unstable breathing when patients shift between varying breathing patterns during sleep. Usually, a person with periodic breathing will go through cycles in which the breath rate becomes slow and deep before quickening and becoming shallow. This process often results in central sleep apnea events as well. See also: Apnea; Apnea Event  

Pressure Setting:  A PAP therapy pressure setting, also called therapy pressure, is the amount of airflow delivered.. A PAP therapy machine will measure the airflow pressure in centimeters of water (cm H2O), as it is the easiest method for distinguishing pressure levels in tubes. For example, most patients require pressure settings between 6 and 14 cmH2O, with the average pressure being about 10. When the pressure is too low, a patient may suffer further sleep apnea events or hypopneas, while a high pressure setting may make the device less bearable. See also: Therapy Pressure  

Pressure Port:  Pressure ports are parts of PAP therapy masks where tubing and/or pressure lines can be directly connected, such that oxygen and/or pressure can be monitored easily from the port. 

Pulse Rate:  A pulse rate is the number of heart beats in a 60-second interval. A patient’s pulse rate is measured by oximeters and other devices using sensors to read each beat upon the skin. See also: Oximeter  

Polysomnography (PSG):  A polysomnography (PSG) is a sleep test often taken in sleep centers or sleep research institutes. PSG tests monitor sleep patterns to assess the patient’s overall quality of sleep and sleep health. Most often, a person will undergo a PSG when it is suspected that they have a sleep disorder. See also: Home Sleep Test (HST)  

Polysomnogram:  A polysomnogram (also a PSG) is a record taken at a polysomnography exam, often including pulse, eye movements, body movements, awakenings, brain activity, and other events such as apneas or hypopneas.  

Radiated Noise:  See Conducted Noise

Rainout:  Rainout is the condensation that can occur in masks or mask tubing during PAP therapy. If a PAP therapy environment becomes too cold, the amount of water vapor held by the air is lowered, causing standard condensation, which is referred to as “rainout” in PAP therapy. PAP therapy humidifiers can be adjusted to reverse the condensation effect, or may do this automatically, depending on the model and settings. See also: Humidification; Climate Control  

Ramp:  Ramp refers to the slow start of PAP therapy devices, allowing for the patient to have a gradual rising of pressure, rather than an immediate maximum pressure setting. This is a comfort feature that helps sleep apnea patients fall asleep taking easier breaths at the onset of therapy. The pressure setting gradually rises to the set maximum, but ramp timing can be adjusted to suit the needs of the patient, making it last longer or shorter as needed. See also: Pressure Setting  

REM sleep:  Rapid Eye Movement (REM) sleep, also referred to as stage 4 sleep, is the stage of sleep when much of dreaming occurs, and the eyes dart back and forth periodically. The first three stages of sleep are known as Non-REM (or NREM) sleep. See also: Non-REM  

Respiratory Effort:  Respiratory effort is the effort made when breathing in and out. This can be measured by the movements of the chest and stomach, but more accuracy, a test called a respiratory inductance plethysmography is used.  

Respiratory System:  The respiratory system is made up of all the organs in your body that help you breathe. It is made up of the upper and lower airways or respiratory tracts. This includes the lungs and trachea in the lower region, and the mouth, nose, and larynx toward the surface. See also: Upper Airway; Lower Airway  

Respiratory Rate:  A respiratory rate is the rate at which breathing occurs, measured as the number of inhalations and exhalations in each minute.  

ResScan:  ResScan is the name of ResMed’s data management program used in the cloud. Like many online sleep data applications, it is used as a real-time interface for the assessment of therapy data and determining patient progress.  

Restless Leg Syndrome (RLS):  Restless leg syndrome (RLS) is a sleep disorder that involves leg movements such as kicking in the night. This can occur unconsciously, but also due to intense urges that cause the patient to become restless and irritable, often only relieved by getting up or moving the legs. RLS is a common sleep disorder.  

Sleep Apnea:  Sleep apnea is the general term for events in the night that involve a cessation of breathing. Sleep apnea is the most common type of sleep-disordered breathing (SDB). See also: Sleep-Disordered Breathing  

Sleep Architecture:  Sleep architecture refers to how a person passes through cycles of sleep stages on a typical night. This also includes awakenings, sleep latency, and other factors that affect the cycles. See also: Sleep Cycle: Sleep Stages; Sleep Latency  

Sleep Cycle:  A sleep cycle is a single transition through each of the four sleep stages. a cycle typically lasts about 90 to 110 minutes, but every person has unique sleep architecture, and sleep disorders will have a serious effect on cycle progress. Generally, most healthy adults will go through four to six cycles in a full night of sleep, but children have much shorter cycles and may pass through many on their way to waking.  

Sleep-Disordered Breathing (SDB):  Sleep Disordered Breathing (SDB) is the term used to describe respiratory disorders which are characterized by abnormal breathing patterns at night. The SDB category includes all forms of sleep apneas, hypopneas, flow limitations, upper airway resistance and types of snoring. See also: Sleep Apnea  

Sleep Lab:  A sleep laboratory is a special lab for sleep-related breathing disorders. Sleep labs help patients to assess and properly diagnose a sleep disorder, but also perform ongoing sleep studies and research meant to improve the science of sleep and sleep health in general. See also: Sleep Specialist  

Sleep Latency:  Sleep latency, also called sleep onset latency (SOL), is the period between laying down at night and falling asleep. A longer sleep latency is associated with sleep problems, while a shorter sleep latency is related to good sleep health (sleep efficiency).  

Sleep Report:  It is important to know the significance of your CPAP readings. Medicare requires patients to use their CPAPs at least 4 hours a night an average of 5 nights a week. Keeping track of your usage will help you stay in compliance with Medicare or other insurance companies that may place usage requirements on the continued availability and insurance reimbursement of the machine. CPAP machines can display sleep reports covering one day to one year. Below are three readings on the same patient: one week, six months and one year. Notice that the patient was very compliant with using therapy, wearing it 361 days out of 365 and sleeping an average of 7.6 hours per night.  

Sleep Specialist:  A sleep specialist is a doctor who is board certified in the subspecialty of sleep medicine. He or she is specialized in the testing, assessment, and diagnosis of sleep disorders and other sleep-related problems.  

Sleep Stage:  Sleep stages are characterized by different brain wave patterns during sleep. Each of the four sleep stages makes up a single sleep cycle, and several sleep cycles are passed through each full night of sleep. during sleep, you go through distinct and important stages throughout the night. Each stage has a purpose. You must enter each to have  

Sleep Test:  A sleep test or sleep study is an exam by sleep professionals to determine the overall sleep health and patterns of a patient. During a sleep test, diagnostic equipment records a number of variables as data that is later assessed for patterns and conditions. This includes sleep timing, waking episodes, apneas or hypopneas, blood oxygen levels, and other factors.  

Snore Index:  A snore index is a measure of the pressure output of snoring during the night. This measurement is used as part of the overall sleep test assessment process, and is included as data into the results. See also: Sleep Study  

Therapy Pressure:  See Pressure Setting  

TiControl:  TiControl is ResMed’s version of Inspiration Time (Ti), which also includes user-friendly setting features for optimal Bilevel therapy experiences. TiControl allows for minimum and maximum inspiratory time limits to accommodate patient needs. See also: Inspiration Time (Ti)  

Tidal Volume:  Tidal volume Refers to the volume of air that you breathe in and out in one breath, when you are in a resting (not active) state.  

Titration:  Titration is the process by which a new patient or sleep physician sets the proper pressure for a PAP therapy device. This can be done by using the patient AHI (apnea-hypopnea index) or by raising and lowering the air pressure to find the best setting. See also: Automatic Positive Airway Pressure (APAP)  

Tracheotomy:  A tracheotomy is a surgical procedure in which an incision is made in a patient’s throat to insert an oxygen tube. This procedure is still used in some sleep apnea cases, and was once the standard treatment for sleep apnea complications that had no other options. See also: Invasive Ventilation  

Upper Airway:  The upper airway consists of the nose, throat, epiglottis, and pharynx. These are the airway features closest to the external environment as air flows in and out of the body. The lower airway includes the deeper organs such as the lungs and trachea. The larynx stretches through both regions. See also: Lower Airway  

Variable Positive Airway Pressure (VPAP):  Variable positive airway pressure (VPAP) is another name for bilevel or BiPAP technology, which delivers two pressure settings during exhalation and inhalation. See also: Bilevel; BiPAP  

XPAP:  XPAP is an all-purpose acronym used more recently to refer to the various forms of PAP therapy in a general manner. XPAP refers to CPAP, APAP, BiPAP, VPAP, ASV, and other forms of PAP therapy.    

 

Sources

American Academy of Sleep Medicine - https://aasm.org/

American Sleep Apnea Association - https://www.sleepapnea.org/

ATS Journals - https://www.atsjournals.org/doi/abs/10.1164/ajrccm-conference.2018.197.1_MeetingAbstracts.A3962

Philips Respironics - http://www.respironics.com/

ResMed - https://www.resmed.com/us/en/healthcare-professional.html

Sleep Education - http://sleepeducation.org/essentials-in-sleep/sleep-apnea/overview-facts

UCLAhealth.org - https://www.uclahealth.org/

WebMD - https://www.webmd.com/