Consensus Statement

Section I - Diagnosis and Medical Management

Glossary

Apnea: A respiratory pause which may be central (no respiratory effort), obstructive (effort without airflow), or mixed. Short (<15 seconds) central apnea can be normal at all ages. Short apnea is pathological if it is associated with cyanosis, marked pallor, hypotonia or bradycardia.

Apnea Program: A hospital based program under the direction of a designated apnea specialist which usually includes a Children's Special Health Care Services-designated multispecialty Apnea Clinic. This program, comprised of a variety of health care professionals, provides consultation and management of patients with apnea and apnea-related medical conditions. It is also responsible for coordinating patient care with community physicians, home medical equipment providers and public and community health resources.

Apnea of Infancy (AOI): An unexplained episode of cessation of breathing for 20 seconds or longer, or a shorter respiratory pause associated with bradycardia, cyanosis, pallor, and/or marked hypotonia. The terminology "apnea of infancy" generally refers to apnea in infants who are older than 37 weeks postconceptional age at onset. The diagnosis of AOI should be reserved for those infants for whom no specific cause of an Apparent Life-Threatening Event (ALTE) can be identified. In other words, these are infants whose ALTE was idiopathic and believed to be related to apnea.

Apnea of Prematurity (AOP): Pathologic apnea in a preterm infant, often accompanied by periodic breathing (q.v.). Apnea of prematurity usually ceases by 37 weeks postconceptional age but occasionally persists beyond 40 weeks. AOP is a developmental phenomenon. It is sometimes treated with methylxanthines.

Apparent Life-Threatening Event (ALTE): The term "ALTE" describes a clinical syndrome comprised of an episode that is frightening to the observer and that is characterized by some combination of apnea (central or obstructive), color change (usually cyanotic or pallid but occasionally erythematous or plethoric), marked change in muscle tone (usually marked hypotonia), choking, or gagging. In some cases, the observer fears that the infant has died. Previously used terminology such as "aborted crib death" or "near-miss SIDS" should be abandoned because it implies a possibly misleading close association between this type of spell and SIDS.

Asymptomatic Premature Infants: Preterm infants who either never had AOP or whose AOP has resolved.

Bradycardia: A drop in the heart rate below the age-specified rate for greater than 5 seconds. Monitor bradycardia alarms are usually set to these generally accepted limits:

Central Apnea: Cessation of respiration caused by failure of the brain's respiratory center.

Compliance: Adherence to a treatment plan. Compliance with any prescribed treatment is influenced by a number of factors, including availability of the resources to carry out the treatment, patients' beliefs about the importance of a treatment, and side effects of the treatment. It is important to identify and remove barriers to compliance. Compliance may be documented through a number of mechanisms including parents' self-report, the use of memory monitors, and observations made at home visits by the home medical equipment providers and community health nurses. Compliance with the home monitoring program includes attendance at scheduled appointments with the physician managing the patient's apnea, the home medical equipment providers, and the community health nurse. It is appropriate to discontinue home monitoring when there is noncompliance unless the infant is still symptomatic or otherwise at high risk for pathologic apnea. In this situation, efforts to bring about compliance should be continued and include, as needed, a referral to Protective Services.

Electromyogram (EMG): The recording of electrical activity in muscle, sometimes used to help determine sleep state when polysomnography is performed.

Electrooculogram (EOG): The recording of eye movement, used to determine sleep state (e.g. REM sleep) during poly-somnography.

Gastroesophageal Reflux (GER): Flow back of stomach content into the esophagus caused by inappropriate relaxation of the stomach's cardiac sphincter. Sometimes associated with apnea.

Heart Rate Trend: The printed or displayed tracing of heart rate changes over time.

Long QT Syndrome: A cardiac disorder characterized by a prolonged QT interval that can lead to sudden death from ventricular arrhythmia. A QT interval greater than 440 msec after correction for heart rate (the "QTc") is considered prolonged. There is evidence that the long-QT syndrome is the cause of some SIDS deaths.

Medium Chain Acetyl Co-A Transaminase Deficiency: An inborn error of metabolism that has been associated with apnea and sudden death, probably from sudden profound hypoglycemia.

Methylxanthines: A class of medications including theophylline and caffeine used as respiratory stimulants.

Mixed Apnea: Cessation of respiration caused by a combination of obstructed respiratory effort and central apnea.

Munchausen Syndrome by Proxy (MSBP): A disorder in which a person falsifies or creates illness in another person to gain access to needless medical evaluations, operations, and treatments for their own emotional gain. In most cases the victim is a child between the ages of infancy to nine years. Sometimes siblings in the same family are affected. The perpetrator is almost always the mother; rare cases describing the father or babysitter are documented. The perpetrator is usually overly attached to the medical staff and has some medical training or is close to someone with medical training. She or he may have a history of psychiatric illness or personality disorder; she or he often presents as a loving, caring parent. The most commonly fabricated conditions are: apnea, seizures, gastrointestinal disturbances, failure to thrive, infections and rashes.

Obstructive Apnea: Failed respiratory effort caused by airway obstruction.

Pathologic Apnea: A respiratory pause is pathological if it last 20 seconds or longer, or if it is associated with cyanosis, abrupt marked pallor, hypotonia, or bradycardia. Pathologic apnea may be of central, mixed or obstructive origin.

Periodic Breathing: A breathing pattern in which there are three or more respiratory pauses of greater than three seconds' duration with less than 20 seconds of respiration between pauses. Periodic breathing may be a normal event and may be associated with upper respiratory infections. It is rare after the age of 3 to 4 months. Methylxanthine administration usually abolishes periodic breathing.

Preterm Infant: An infant born prior to the 38th week post conception.

Pulse Oximetry: An indirect method of measuring arterial pO2. While the current state of pulse oximetry doesn't warrant the general use of these devices in the home, special circumstances may arise, including patients on assisted ventilation at home and children with severe bronchopulmonary dysplasia. In those cases pulse oximetry data can be merged into the data stream of some monitors as an additional channel.

Respiratory waveform: The printed or displayed tracing of chest wall movement over time.

Sudden Infant Death Syndrome (SIDS): The sudden death of an infant under one year of age which remains unexplained after the performance of a complete postmortem investigation, including autopsy, death scene examination, and review of the case history.

Symptomatic Premature Infant: Preterm infants who continue to have pathologic apnea at the time they otherwise would be ready for discharge.

Tachycardia: Rapid heart beat. Tachycardia alarms on home cardiorespiratory monitors are usually set 60 to 80 beats per minute above the patient's baseline heart rate.

Transthoracic Impedance (TTI): The change in electrical resistance detected over the chest wall by a cardiorespiratory monitor. This change in resistance reflects chest wall movement which is a measure of respiratory effort but not necessarily successful respiration.