Severe disruptions produce significant airway blockage in the night during sleep, causing the symptoms and complications of obstructive sleep apnea. Our instinctive drive to breath decreases during sleep, and breathing patterns change during the different phases of sleep. There is marked relaxation of the muscles in the upper airway region. This relaxation and subsequent narrowing of the upper airway causes increased resistance to airflow as the tissues fall together into a more relaxed postion. When we dream, the the muscles of the upper airway relax even more.
Breathing becomes more erratic with regard to rate and depth.
There are frequent pauses. If this natural state of sort of borderline ventilation is disturbed by any additional obstruction, significant respiratory impairment can result. The child must constantly arouse to the point where muscle tone in the upper airway increases enough to allow breathing to resume. This can happen literally hundreds of times a night, making normal rest impossible. Over time, these disturbed levels of blood gases cause abnormal constriction of the vessels in the lungs and other direct toxic effects on the body.