What is an endoscope? Simply put, an endoscope is an instrument that allows access to the inside of the body for exploration. It transmits a view of the inside of the body to the outside of the body through special equipment and through a screen for the doctor to observe. In addition to direct observation with the naked eye through the endoscope, the doctor can also remove small pieces of tissue from the digestive organs through the endoscope to observe the lesions under the microscope. Depending on the site of examination, endoscopes for the gastrointestinal tract include esophagoscopy, gastroscopy, duodenoscopy, small boweloscopy, colonoscopy, sigmoidoscopy (Figure 3-3), and proctoscopy. Gastroscopy can be performed whenever a patient is suspected of having a disease of the esophagus, stomach, or duodenum. During the examination, the gastroscope enters the body through the mouth of the person being examined. If the patient is suspected of having a disease of the colon, colonoscopy can be performed, and the colonoscope enters the body through the anus of the patient. Endoscopy is not only a diagnostic tool, but doctors can also use endoscopy to perform gastrointestinal treatments such as hemostasis of the gastrointestinal tract, removal of polyps and early cancers, and removal of stones in the bile ducts. What should I do before and after a gastroscopy? Because people who have had certain diseases are not suitable for endoscopy, it is important to tell your doctor in detail about the diseases you have had before undergoing endoscopy. The day before the gastroscopy, you should not smoke, drink alcohol, or eat irritating foods such as chili or garlic, and you should not eat too much food for dinner. On the day of the examination, you need to have an empty stomach, i.e. you should not eat any food or drink any water after waking up early. Before the examination, you should empty your bowels and urine. Loosen your clothes and belt and take out your dentures during the examination. Do not be nervous during the examination and keep the whole body in a relaxed state. While the doctor inserts the gastroscope, the patient should keep taking deep breaths so that the larynx is more relaxed and the gastroscope can easily pass. You must rest for 1 hour after the examination, and you cannot drive or work at height that day. 2 hours after the end of the examination, you can start to eat a little slightly hot liquid food, such as thin rice, noodle soup. There may be slight pain in the throat 1 to 2 days after the examination, and no special treatment is usually necessary. Important Note Patients who have just undergone barium gastrointestinal angiography should not undergo gastroscopy within 3 days because the residual barium in the stomach will affect the endoscopic observation. Patients whose stomach biopsies have been clamped should eat liquid food only 4 hours after the end of the examination to avoid food irritation or damage to the clamped parts of the stomach tissue. After the examination, you need to pay attention to the color of the stool. If symptoms such as blood in the stool, black stool or abdominal pain appear, you should go to the hospital immediately and ask for doctor’s help. Who is not suitable for gastroscopy? Not everyone is suitable for gastroscopy. The following people are not suitable for gastroscopy People who are unwilling or unable to cooperate, such as psychiatric patients and people with mental retardation. Patients with physical factors that interfere with gastroscopy access, such as patients with severe spinal deformities. People with acute inflammation of the pharynx, such as those who have acute pharyngitis or purulent tonsillitis. Patients who are in the midst of a bronchial asthma attack. Patients with severe cardiovascular, pulmonary, and cerebral diseases, such as those suffering from angina pectoris and heart failure. Patients who are suspected of having gastric perforation. What should I do before and after the colonoscopy? Because people with certain diseases are not suitable for endoscopy, it is important to tell your doctor in detail about the diseases you have had before undergoing the examination. 3 days before the colonoscopy, you should eat a small amount of food; 1 day before the colonoscopy, you should eat only liquid food; and on the morning of the examination, you should not eat. Take the laxative prescribed by the doctor 4 hours before the examination so that the stool can be emptied to avoid fecal interference with the examination. However, be careful not to take laxatives on your own. During the examination, you can relax your abdomen by breathing slowly and deeply. Patients who have had their intestinal mucosa removed by colonoscopy should watch for blood in the stool and abdominal pain after the examination. Who is not suitable for colonoscopy? Patients with anal or rectal strictures. Patients with very severe ulcerative colitis. Pregnant women. Is it painful to undergo a gastrointestinal endoscopy? The endoscope tube is less than 1 cm in diameter and is flexible enough to enter the stomach and intestines without causing pain to the patient. The patient will be more or less uncomfortable during the endoscopy, such as a small burst of nausea due to irritation when the mouth of the gastroscope passes through the pharynx, but the nausea will be significantly reduced as soon as the body of the mirror enters the esophagus. And before doing gastroscopy, the doctor will give the patient some anesthetic spray to the pharynx; before doing colonoscopy, the doctor will give the patient intestinal relaxation drugs, all of which can reduce the patient’s pain.