An upper endoscopy involves inserting an endoscope, which is a thin tube with a camera and light at the edge, into the mouth, throat and esophagus, letting the physician examine the esophagus, stomach and small intestine, explains WebMD. During an endoscopic retrogade cholangiopancreaticography, a physician views images of the pancreas, gallbladder and nearby organs.
Another form of endoscopy is endoscopic ultrasound, which merges upper endoscopy with an ultrasound test to view pictures of the digestive tract, states WebMD. During an endoscopy, a physician sees images of the inside of the body on a colored television monitor.
When performing an upper endoscopy, a doctor typically monitors a person's heart rate, blood pressure and breathing by attaching monitors to the person's body, notes Mayo Clinic. The procedure sometimes requires administering a sedative drug through a vein in the forearm, allowing a person to relax during the upper endoscopy. The doctor may also request the individual undergoing the procedure to wear a mouth guard to keep his mouth open and spray an anesthetic into the person's mouth to make his throat numb.
An endoscopy helps doctors diagnose abdominal pain, gastritis, ulcers, trouble swallowing or digestive tract bleeding, according to WebMD. The test also enables them to determine the cause of bowel habit changes or colon growths. Doctors sometimes use the procedure to obtain a tissue sample to identify the presence of a disease.