These day-procedures are commonly performed under procedural sedation.
Most sedated patients will not remember the entire endoscopy procedure. However, during procedural sedation, some patients may recall fragments of the process. It is important to alert the anaesthetist if one is uncomfortable during the procedure. Oral pain relief and medications to treat nausea will be prescribed if needed.
The Australia and New Zealand College of Anaesthetist (ANZCA) produced an information handout “Anaesthesia for endoscopy” which is the closest information form downloadable here.
Please see risks or anaesthesia for more information here.