Apnea, which means "without breath," includes three types: obstructive, central and mixed. Obstructive is the most common. In all three, people with untreated sleep apnea stop breathing repeatedly during their sleep. These repeated pauses in breathing last at least 10 seconds. In more severe cases, hundreds of episodes of apnea may occur every night. A bed partner familiar witht he person experiencing the apnea may report cessation of breathing, choking, gasping, and frequent awakenings. This causes excessive daytime sleepiness and decreased concentration.
Obstructive sleep apnea is caused by a blockage of the airway, usually when the soft tissue in the rear of the throat collapses and closes during sleep. Blockage of the airway can be partial or complete and results in ventilation that is decreased (hypopnea) or absent (apnea). These episodes cause a drop in the saturation of oxygen in the blood.
In central sleep apnea (CSA), the airway is not blocked but the brain fails to signal the muscles to breathe.
Obesity and Sleep Disorders: Implications for Bariatric Patients
Mahmood I. Siddique, DO, FACP, FCCP, FAASM, Iftekhar Mahmud, MD and Reshmi M. Siddique, PhD
