Obstructive Sleep Apnea (OSA) is blockage of the airway that occurs during sleep. The blockage happens due to excess tissue in the airway (tongue, palate, uvula, tonsils) that relaxes during sleep and then crowds into the airway. This lack of breathing leads to a drop in oxygen, which then causes you to wake up to breathe. The process occurs repeatedly during the night, resulting in a lack of sleep and stress on your heart and body organs. Many people with untreated OSA experience the following symptoms: daytime sleepiness, fatigue, depression, irritability, mood disorders, elevated blood pressure, obesity and difficulty losing weight, morning headaches, snoring and insomnia. If left untreated, OSA can increase your risk for heart attack, stroke, type 2 diabetes, atrial fibrillation, coronary artery disease and congestive heart failure.