A gastroscopy is a test that allows your doctor to look inside your food-pipe (oesophagus), stomach and the first part of the small intestine (duodenum). The test is done using a narrow, flexible, tube-like telescope called an endoscope. The endoscope is passed through the mouth and into the oesophagus and down towards the stomach. The test may also be simply referred to as an endoscopy, or OGD (oesophago-gastro-duodenoscopy).
A gastroscopy can help find out what is causing symptoms such as indigestion, upper abdominal pain, vomiting or bleeding. It is also used to check for certain gastrointestinal conditions such as inflammation, ulcers and early signs of cancer. Sometimes, a gastroscopy is used to confirm the results of other tests – a barium meal, for example.
During the procedure, your doctor may take one or more biopsies (small samples of tissue) for examination in a laboratory.
Depending on your symptoms and circumstances, it may be possible to diagnose your condition using a different test.
Gastroscopy is routinely done as an out-patient or day case.
You may be given a sedative to help ensure that you are relaxed and comfortable during the procedure. Afterwards, most people have very little memory of the test.
For your doctor to see the lining of the stomach and duodenum clearly, your stomach needs to be completely empty. To help clear it out you must follow the fasting instructions in your admission letter. In general, you must not eat or drink for six to eight hours before the test. You may be allowed to sip clear fluids for up to two hours before the procedure. Your hospital will give you detailed advice beforehand.
If you normally take medication (eg tablets for blood pressure), continue to take this as usual, unless your doctor specifically tells you not to. If you are unsure about taking your medication, please contact the hospital.
When you arrive at the hospital, you may be asked to answer some questions about your health and any medicines you are taking. You should tell your doctor or nurse if you are allergic to any medication and whether you suffer from asthma, hayfever or eczema.
It’s important to tell your doctor or nurse if you have any dental crowns, bridges or loose teeth. These can be vulnerable to damage by the endoscope, though special care will be taken to prevent this. You may also have a blood test before the procedure.
You may be asked to take off your shirt or top and put on a hospital gown. If you have them, you will be asked to take out any removable dentures or dental plates and contact lenses. You will be asked to take off your glasses and jewellery. These will be kept safe for you.
Your doctor may spray a local anaesthetic into the back of your throat or give you a lozenge to suck to numb the throat area.
If you are having sedation, a small plastic tube (cannula) will be placed in a vein on the back of your hand. The sedative will be injected through the cannula, and you should start to feel relaxed and drowsy almost immediately. Sedatives can sometimes affect your breathing. While you are sedated, the amount of oxygen in your blood will be monitored constantly through a small clamp on your finger and you may be given extra oxygen through a mask.
With you resting on your side, your doctor will place a mouth guard over your teeth before carefully putting the endoscope into your mouth. You will be asked to swallow to help the endoscope pass into the oesophagus and down towards the stomach. You should be able to breathe normally during this test. A nurse will help the doctor by using a suction tube to remove excess saliva from your mouth during the procedure.
Air is then usually pumped through the tube and into the stomach to make it expand and the stomach lining easier to see. When this happens, you may briefly feel a sensation of fullness or nausea.
A camera lens at the end of the endoscope sends pictures from the inside of your body to a video screen. Your doctor will look at these images to examine the lining of your oesophagus, stomach and duodenum.
If necessary, your doctor will take a biopsy and/or remove polyps. This is done using special instruments passed inside the endoscope, and is quick and painless but you may feel a slight pinch.
When the examination is finished, the endoscope is taken out quickly and easily. You will be in the treatment room for about 20 to 30 minutes. The procedure will not hurt but it may be a bit uncomfortable.
If you have a biopsy, the results will be ready several days later and will usually be sent in a report to the doctor who recommended the test. Other findings may be discussed before you leave the hospital. If you have sedation, it’s a good idea to have someone with you if the results are being discussed immediately after the procedure, as you may not remember the details clearly.
The effects of any sedative may last longer than you expect. Do not drive, drink alcohol, operate machinery or sign legal documents until your doctor tells you that it’s safe to do so. This will be at least 24 hours after your procedure. This means that you will have to arrange for someone to drive you home. If you are in any doubt about driving, please contact your motor insurer so that you are aware of their recommendations, and always follow your doctor’s advice.
You must be aware that your car insurance is not valid for 24hrs after a gastroscopy so that if you drive and have an accident within 24hrs of a gastroscopy you will not be covered by your car insurance and you will be liable to pay all costs related to that accident whether you were at fault or not.
Once home, you should take it easy for the rest of the day and arrange for someone to stay with you for the first 24 hours. Most people experience no problems after the procedure. However, please contact your doctor if you develop any of the following symptoms:
Gastroscopy is a commonly performed and generally safe procedure. For most people, the benefits in terms of having a clear diagnosis are much greater than any disadvantages. However, as with all medical procedures, a gastroscopy carries an element of risk. In order to make an informed decision and give your consent, you need to be aware of the possible side-effects and the risk of complications.
Side-effects are the unwanted but mostly temporary effects of a successful procedure. After having a gastroscopy you may:
Complications are unexpected problems that can occur during or after the procedure. Most people are not affected. Complications of gastroscopy are uncommon but some people find that it takes a little while for their heart rate and breathing to settle after a gastroscopy. You may need to have oxygen through a mask temporarily.Sedatives can affect your breathing. If you are having a gastroscopy under sedation, there is a slight risk that your heart may stop during the procedure. Resuscitation medication, equipment, and trained personnel are available to help with this.
A more common complication of gastroscopy is a chipped tooth or damaged crown which can occur when biting down on the mouthguard that will be placed in your mouth to stop you chewing on the gastroscope. This may require dental repair to correct. Please inform the gastroenterologist of any plates, caps, crowns or dentures prior to gastroscopy.
A cut lip can also occur as a result of the mouthguard trapping part of the lip between it and your teeth. This may require ice and or stitches.
If you have not fasted properly prior to gastroscopy or if you have a large amount of gastric mucous in your stomach it is possible that you may vomit under anaesthetic and aspirate stomach fluids into your lungs. This can cause pneumonia and require hospital admission, intravenous antibiotics and oxygen to correct.
If biopsies of the lining of your stomach, esophagus or duodenum are taken you may have some bleeding after the gastroscopy which may cause your stools to turn black or you to vomit blood. Very rarely, this may be severe enough to require a blood transfusion or a repeat gastroscopy or even open surgery to stop the bleeding. This is more likely of you are currently taking blood thinning medication such as warfarin, aspirin or clopidogrel. Please discuss this with your endoscopist prior to your gastroscopy if you are taking any of these medications.
It’s possible to damage or, in very rare cases, perforate the oesophagus, stomach or duodenum during the procedure – this can lead to bleeding and infection, which may require further surgery or treatment with medicines.
Your doctor will be experienced at performing gastroscopies, but even so a few are not successfully completed and may need to be repeated.
Ask your doctor to explain how these risks apply to you. The exact risks will differ for every person. This is one of the reasons why we have not included statistics here.
I have read and understood clearly all the reasons for gastroscopy, the alternatives to gastroscopy, risks of gastroscopy and the possible complications of gastroscopy contained in this document supplied to me by Dr Froomes. Having read and understood this document and all the information contained in it, I find nothing that would prevent me from consenting to undergo gastroscopy. Therefore, I give my written consent to undergo gastroscopy.
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