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Upper Gastrointestinal Endoscopy

Test Overview

An upper gastrointestinal (or GI) endoscopy is a test that allows your doctor to look at the inside of your esophagus, stomach, and the first part of your small intestine, called the duodenum. The esophagus is the tube that carries food to your stomach. The doctor uses a thin, lighted tube that bends. It is called an endoscope, or scope.

The doctor puts the tip of the scope in your mouth and gently moves it down your throat. The scope is a flexible video camera. The doctor looks at a monitor (like a TV set or a computer screen) as he or she moves the scope. A doctor may do this procedure to look for ulcers, tumours, infection, or bleeding. It also can be used to look for signs of acid backing up into your esophagus. This is called gastroesophageal reflux disease, or GERD. The doctor can use the scope to take a sample of tissue for study (a biopsy). The doctor also can use the scope to take out growths or stop bleeding.

Why It Is Done

An upper GI endoscopy may be done to:

  • Find what's causing you to vomit blood.
  • Find the cause of symptoms, such as upper belly pain or bloating, trouble swallowing (dysphagia), vomiting, or unexplained weight loss.
  • Find the cause of an infection, such as helicobacter pylori (H. pylori).
  • Find problems in the upper gastrointestinal (GI) tract. These problems can include:
  • Check the healing of stomach ulcers.
  • Look at the inside of the stomach and upper small intestine (duodenum) after surgery.
  • Look for a blockage in the opening between the stomach and duodenum.

Endoscopy may also be done to:

  • Check for an injury to the esophagus in an emergency. (For example, this may be done if the person has swallowed poison.)
  • Collect tissue samples (biopsy) to be looked at in the lab.
  • Remove growths (polyps) from inside the esophagus, stomach, or small intestine.
  • Treat upper GI bleeding that may be causing anemia.
  • Remove foreign objects that have been swallowed or food that is stuck.
  • Treat a narrow area of the esophagus.
  • Treat Barrett's esophagus.

How To Prepare

Procedures can be stressful. This information will help you understand what you can expect. And it will help you safely prepare for your procedure.

Preparing for the procedure

  • Do not eat or drink anything for 6 to 8 hours before the test. An empty stomach helps your doctor see your stomach clearly during the test. It also reduces your chances of vomiting. If you vomit, there is a small risk that the vomit could enter your lungs. (This is called aspiration.) If the test is done in an emergency, a tube may be inserted through your nose or mouth to empty your stomach.
  • Do not take sucralfate or antacids on the day of the test. These medicines can make it hard for your doctor to see your upper GI tract.
  • If your doctor tells you to, stop taking iron supplements 7 to 14 days before the test.
  • Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.
  • Understand exactly what procedure is planned, along with the risks, benefits, and other options.
  • Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your procedure. Your doctor will tell you if you should stop taking any of them before the procedure and how soon to do it.
  • If you take a medicine that prevents blood clots, your doctor may tell you to stop taking it before your procedure. Or your doctor may tell you to keep taking it. (These medicines include aspirin and other blood thinners.) Make sure that you understand exactly what your doctor wants you to do.
  • Make sure your doctor and the hospital have a copy of your advance care plan. If you don't have one, you may want to prepare one. It lets others know your health care wishes. It's a good thing to have before any type of surgery or procedure.

How It Is Done

How is an upper GI endoscopy done?

Before the test

Before the test, you will put on a hospital gown. If you are wearing dentures, jewellery, contact lenses, or glasses, remove them. For your own comfort, empty your bladder before the test.

Blood tests may be done to check for a low blood count or clotting problems. Your throat may be numbed with an anesthetic spray, gargle, or lozenge. This is to relax your gag reflex and make it easier to insert the endoscope into your throat.

During the test

You may get a pain medicine and a sedative through an intravenous (I.V.) line in your arm or hand. These medicines reduce pain and will make you feel relaxed and drowsy during the test. You may not remember much about the actual test.

You will be asked to lie on your left side with your head bent slightly forward. A mouth guard may be placed in your mouth to protect your teeth from the endoscope (scope). Then the lubricated tip of the scope will be guided into your mouth. Your doctor may gently press your tongue out of the way. You may be asked to swallow to help move the tube along. The scope is no thicker than many foods you swallow. It will not cause problems with breathing.

After the scope is in your esophagus, your head will be tilted upright. This makes it easier for the scope to slide down your esophagus. During the procedure, try not to swallow unless you are asked to. Someone may remove the saliva from your mouth with a suction device. Or you can allow the saliva to drain from the side of your mouth.

Your doctor will look through an eyepiece or watch a screen while slowly moving the endoscope. The doctor will check the walls of your esophagus, stomach, and duodenum. Air or water may be injected through the scope to help clear a path for the scope or to clear its lens. Suction may be applied to remove air or secretions.

A camera attached to the scope takes pictures. The doctor may also insert tiny tools such as forceps, clips, and swabs through the scope to collect tissue samples (biopsy), remove growths, or stop bleeding.

To make it easier for your doctor to see different parts of your upper GI tract, someone may change your position or apply gentle pressure to your belly. After the exam is done, the scope is slowly pulled out.

How is an upper GI endoscopy done?

You will feel groggy after the test until the medicine wears off. This usually takes a few hours. Many people report that they remember very little of the test because of the sedative given before and during the test.

If your throat was numbed before the test, don't eat or drink until your throat is no longer numb and your gag reflex has returned to normal.

How long the test takes

The test usually takes 30 to 45 minutes. But it may take longer, depending on what is found and what is done during the test.

Watch

How It Feels

You may notice a brief, sharp pain when the intravenous (I.V.) needle is placed in a vein in your arm. The local anesthetic sprayed into your throat usually tastes slightly bitter. It will make your tongue and throat feel numb and swollen. Some people report that they feel as if they can't breathe at times because of the tube in their throat. But this is a false sensation caused by the anesthetic. There is always plenty of breathing space around the tube in your mouth and throat. Remember to relax and take slow, deep breaths.

During the test, you may feel very drowsy and relaxed from the sedative and pain medicines. You may have some gagging, nausea, bloating, or mild cramping in your belly as the tube is moved. If you have pain, alert your doctor with an agreed-upon signal or a tap on the arm. Even though you won't be able to talk during the procedure, you can still communicate.

The suction machine that's used to remove secretions may be noisy, but it doesn't cause pain. The removal of biopsy samples is also painless.

Risks

Problems, or complications, are rare. There is a slight risk that your esophagus, stomach, or upper small intestine will get a small tear in it. If this happens, you may need surgery to fix it. There is also a slight chance of infection after the test.

Bleeding may also happen from the test or if a tissue sample (biopsy) is taken. But the bleeding usually stops on its own without treatment. If you vomit during the test and some of the vomit enters your lungs, aspiration pneumonia is a possible risk.

An irregular heartbeat may happen during the test. But it almost always goes away on its own without treatment.

The risk of problems is higher in people who have serious heart disease. It's also higher in older adults and people who are frail or physically weakened. Talk to your doctor about your specific risks.

Results

Your doctor may be able to talk to you about some of the findings right after your endoscopy. But the medicines you get to help relax you may impair your memory, so your doctor may wait until they fully wear off. It may take 2 to 4 days for some results. Tests for certain infections may take several weeks.

Upper gastrointestinal endoscopy findings

Normal:

The esophagus, stomach, and upper small intestine (duodenum) look normal.

Abnormal:

Inflammation or irritation is found in the esophagus, stomach, or small intestine.

Bleeding, an ulcer, a tumour, a tear, or dilated veins are found.

A hiatal hernia is found.

A too-narrow section (stricture) is found in the esophagus.

A foreign object is found in the esophagus, stomach, or small intestine.

A biopsy sample may be taken to:

  • Find the cause of inflammation.
  • Find out if tumours or ulcers contain cancer cells.
  • Identify a type of bacteria called H. pylori that can cause ulcers or a fungus such as candida that sometimes causes infectious esophagitis.

Many conditions can affect the results of this test. Your doctor will discuss your results with you in relation to your symptoms and past health.

Credits

Current as of: October 19, 2023

Author: Healthwise Staff
Clinical Review Board
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