Author and surgeon explains apnea medical terminology
Posted by Dr. Mark Cruz
Steven Y. Park, MD gave an enlightening presentation about apnea and related breathing disorders during the Airway Focused Dentistry Mini-Residency. The course was co-developed by Dr. Mark A Cruz of Dana Point.
What is obstructive sleep apnea
The discussion of sleep disordered breathing, usually revolves around OSA (obstructive sleep apnea). However, as Dr. Park explained, the criteria used to define OSA is very limited, specifically, and it was largely chosen arbitrarily by early researchers.
Dr. Park went on to explain the specific definition of apnea related terms:
Apnea – An event obstructing at least 90 percent of the airway and lasting at least 10 seconds
Hypopnea – An event obstructing at least 30 percent of the airway, combined with four percent blood oxygen desaturation or arousal from sleep and lasting at least 10 seconds
RERA (Respiratory Event Related Arousal) – An event similar to apnea or hypopnea, but milder; it does not meet the rigid criteria
RDI (Respiratory Disturbance Index) – A number calculated by determining the total of apneas, hypopneas, and RERAs each hour
AHI (Apnea Hypopnea Index) – A number calculated by determining the total of apneas and hypopneas each hour; RERAs are not considered in this number
OSA (obstructive sleep apnea) – The majority of insurance companies and testing laboratories define OSA as having an AHI of five or greater, which excludes patients with a high number of RERAs
UARS (Upper Airway Resistance Syndrome) – A condition defined by events of abnormal breathing and decreased esophageal pressure, which do not meet the criteria of apneas and hypopneas
Although URAS contributes to fatigue, depression, headaches, chronic pain, neurological problems, and a host of other medical concerns, it is often undiagnosed in sleep tests, because they are looking for signs of OAS.
Dr. Cruz, Dr. Park and their colleagues are committed to improving diagnosis and treatment of airway disorders.