During the first 71 minutes of sleep Mr . B _ _ _ _ manifested 83 obstructive apneas, 3 central apneas, 1 mixed apnea and 28 hypopneas, for an elevated apnea + hypopnea index ( AHI ) of 97 events / hr ( * " severe " OSA ).
42.
In 1998, modafinil was approved by the U . S . Food and Drug Administration for the treatment of narcolepsy and in 2003 for shift work sleep disorder and obstructive sleep apnea / hypopnea even though caffeine and amphetamine were shown to be more wakefulness promoting on the Stanford Sleepiness Test Score than modafinil.
43.
Because of their simplicity of use and the ability to provide continuous and immediate oxygen saturation values, pulse oximeters are of critical importance in emergency medicine and are also very useful for patients with respiratory or cardiac problems, especially COPD, or for diagnosis of some sleep disorders such as apnea and hypopnea.
44.
An " event " can be either an apnea, characterised by complete cessation of airflow for at least 10 seconds, or a hypopnea in which airflow decreases by 50 percent for 10 seconds or decreases by 30 percent if there is an associated decrease in the oxygen saturation or an arousal from sleep.
45.
In OSA it appears to be effective to reduce but not eliminate apnea for people with mild to moderate OSA ( Apnea hypopnea index < 30 ) and for people who cannot tolerate CPAP, but within those groups it is not clear why some respond and others do not, and the evidence consists of small clinical trials with follow-up no longer than one year.
