Glossary

apnea – A cessation of breathing attributed to complete airway obstruction during sleep. Specifically, ≥ 90% reduction in airflow for ≥ 10 seconds.

apnea-hypopnea index (AHI) – the combined number of apneic or hypopneic events recorded per hour of sleep during a sleep study.

continuous positive airway pressure (CPAP) – a bedside device that delivers room air to treat a patient with obstructive sleep apnea via a hose-mask assembly to the patient’s nose, mouth or both. The stream of air is continuous. This term is often used interchangeably and loosely with PAP (see below).

hypopnea – Involves episodes of labored breathing or a low respiratory rate that does not meet metabolic needs and is attributed to partial obstruction of the airway. Defined as ≥ 30% decrease in airflow for < 10 seconds. Must include a decrease in respiratory effort and at least one of the following: a reduction in oxygen saturation by 3-4% or an arousal.

mandibular advancement device (MAD) – also known as a mandibular advancement splint (MAS), mandibular repositioning device (MRD), oral appliance (OA).

obstructive sleep apnea (OSA) – A result of recurrent episodes of complete or partial blockage of the upper airway despite respiratory effort.

polysomnograph (PSG) – an overnight sleep study.

positive airway pressure (PAP) – a bedside device that delivers room air to treat a patient with obstructive sleep apnea via a hose-mask assembly to the patient’s nose, mouth or both. PAP devices can deliver air in a continuous manner or in an adjustable manner dependent on patient’s inhalation/exhalation pattern, e.g. bilevel and adaptive-servo ventilation (ASV).