condition in which a person experiences theabsence of breathing (apnea) or diminished breathing efforts(hypopnea) during sleep between snoring intervals. Breathingmay cease for 10 to 20 seconds, possibly as long as 2 minutes.During long periods of apnea, the oxygen level in the blooddrops, the pulse usually becomes irregular, and the blood pressureoften increases. Many people experience sleep apneawithout symptoms, but excessive daytime sleepiness is commonlyreported. Although it occurs most commonly in middleagedmen who are obese and have short thick necks, womenand people of other ages may also experience it. Obstructive sleep apnea (OSA) can result when the airwayis occluded because of the collapse of the hypopharynx(Fig. 34-4) or from other structural abnormalities such asenlarged tonsils and adenoids, a deviated nasal septum, andthyroid enlargement. Narrowing of nasal passagewayscaused by allergic rhinitis or nasal polyps is another factorcontributing to OSA.Some investigators have theorized that sleep apnea mayexplain certain cases of death that occur during sleep.According to recent research, individuals with OSA had“more than twice the number of cardiac deaths during sleepinghours compared to the general population” (O’Brien,2007). In healthy people, OSA may impair cardiac functionover time and lead to the development of heart failure. Ifheart failure has already been diagnosed, OSA may result inprogression of this condition. Sleep apnea and heart failureare a dangerous combination, making it even more importantto recognize and treat OSA.Clinical information and polysomnography can confirmthe diagnosis of sleep apnea. This overnight sleep study consistsof an EEG recording of the stages of sleep and anyepisodes of apnea, an electrooculogram that detects eyemovements, and an electromyographic recording of musclemovement (Shields, 2008). Cardiopulmonary monitoring ofthe arterial oxygen saturation and an electrocardiogram(ECG) to detect any cardiac arrhythmias can also assist inthe diagnosis of obstructive sleep apnea.People with obstructive sleep apnea may become irritableduring the day, fall asleep during monotonous activities,have difficulty concentrating, and exhibit slower reactiontimes. They are also more likely to be involved in motor vehicleaccidents. Alcohol, tobacco, and sleeping pills increase thebreathing disruption that occurs in sleep apnea and should beavoided.