After you check in for your endoscopic ultrasound (EUS) -- a medical procedure to examine the lining and the walls of the upper and lower gastrointestinal tracts -- a nurse will meet with you to review your medical conditions and medications. An intravenous (IV) line will be placed in a vein in your arm. You will proceed to the procedure room, where your blood pressure, pulse, and oxygen level will be carefully monitored. A sedative also will be administered through your IV. You will soon feel drowsy, and while some people fall asleep, others remain awake during the procedure.