Obstructive sleep apnea (OSA).,,,,,,,,,,,,,pptx

Obstructive sleep apnea (OSA).,,,,,,,,,,,,,

1. Obstructive sleep apnea (OSA)

2. Introduction Obstructive sleep apnea (OSA) is characterized by episodes of a complete ( apnea ) or partial collapse (hypopnea) of the upper airway with an associated decrease in oxygen saturation or arousal from sleep.

3. This disturbance results in fragmented, nonrestorative sleep. Other symptoms include loud, disruptive snoring, witnessed apneas during sleep, and excessive daytime sleepiness OSA has significant implications for cardiovascular health, mental illness, quality of life, and driving safety.

4. Etiology Pharyngeal narrowing and closure during sleep is a complex phenomenon, and likely multiple factors play a role in the pathogenesis Sleep-related reduced ventilatory drive and neuromuscular combined with anatomic risk factors are likely to play a significant role in upper airway obstruction during sleep

5. The anatomic factors that promote pharyngeal narrowing include large neck circumference, soft tissue, bone, or vessels.  Many of these structures can lead to increased surrounding pressure of the upper airway resulting in pharyngeal collapsibility and/or insufficient space to accommodate the airflow in a portion of the upper airway during sleep. 

6. In addition, the upper airway muscle tone plays a role as when it decreases, a repetitive total or partial airway collapse results. The most common cause of OSA in adults is obesity, male sex, and advancing age.  The severity of OSA decreases with age when adjusting for BMI

7. Anatomic Factors Micrognathia, retrognathia Facial elongation Mandibular hypoplasia Adenoid and tonsillar hypertrophy Inferior displacement of the hyoid Nonanatomic Risk Factors Central fat distribution Obesity Advanced age Male gender Supine sleeping position Pregnancy

8. Additional Factors Alcohol use Smoking Use of sedatives and hypnotics Associated Medical Disorders Endocrine disorders (e.g., diabetes mellitus, metabolic syndrome, acromegaly, and hypothyroidism) Neurological disorders (e.g., stroke, spinal cord injury, and myasthenia gravis)  Prader Willi syndrome Down Syndrome Congestive heart failure Atrial fibrillation  Obesity hypoventilation syndrome (OHS)