The reason is to prevent desaturation during theendoscopic procedure.
For endoscopic procedures, moderate sedation is used. Hypoxia is a common complication seen during endoscopy, especially in the elderly. Artificial ventilation must be used during endoscopic procedures so that minute ventilation is not reduced.
Airway, respiration and oxygenation are monitored closely during endoscopy to prevent hypoxia. Hypoxia is a condition characterised by decreased levels of oxygen in the body. But rapid adsorption of oxygen causes lung collapse. This condition is known as atelectasis. It may cause pneumonia and infection. The best way to prevent this complication is pre-oxygenation with 80% oxygen.
