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Having a gastroscopy

Read our guide below to find out about having a gastroscopy.

You can also download a PDF version of this patient information by following the link on the right.

You’ve been advised by your GP or hospital doctor to have an investigation known as a gastroscopy.

What is a gastroscopy?

It’s examination of your oesophagus (gullet), stomach and duodenum (small bowel). We use an instrument used called a gastroscope. It’s flexible and has a diameter less than that of a little finger.

Each gastroscope has an illumination channel. This allows light to be directed onto the lining of your upper digestive tract and another which relays pictures back to the endoscopist onto a screen. During the procedure, the endoscopist may take a small tissue sample for microscope analysis. This is called a biopsy.

Why do I need to have a gastroscopy?

You’ve been advised to have this investigation to try and find the cause for your symptoms. It will also help with treatment and if necessary, further investigation.

There are many reasons for this investigation including:

  • indigestion
  • anaemia
  • weight loss
  • vomiting
  • passing black motions
  • vomiting blood
  • difficulty swallowing.

Your appointment

If the time or date isn’t convenient, call the Endoscopy department as soon as possible on 01296 831210. We can reschedule your appointment.

Admission to hospital and consent

During the admission stage, one of the endoscopy specialist nurses will explain your procedure and go through the benefits and risks associated. You’ll have the opportunity to ask questions. Once you’re completely happy, we’ll ask you to sign a consent form. Please note you have the right to withdraw your consent at any
time.

All procedures done in hospital need your consent. This is a legal requirement.

Read this information carefully. It will help you to make an informed choice, and help you understand the risks associated with your procedure.

Arranging a translator

If you don’t speak English, an independent translator should be available to make sure you understand the test. We prefer this to a member of your family or friend translating for you.

If we can’t get proper consent, we’ll cancel the procedure.

What happens to my written consent?

Your signed consent is held in our hospital notes. If you want a copy, we can organise one for your personal records.

Tissue samples

For some procedures, we take tissue samples for microscopic examination. Instead of destroying the samples after this examination, we ask your permission to use these tissue samples for teaching and research purposes. We treat all specimens anonymously.

What does the procedure involve?

You won’t need to undress for the gastroscopy. In the endoscopy room you’ll be made comfortable on a trolley and asked to lie on your left side. A nurse will stay with you throughout the test. The procedure is done by a trained doctor or nurse called an endoscopist.

A plastic mouthpiece will be placed gently between your teeth or gums, to keep your mouth open. The endoscopist will pass the endoscope through the mouthpiece and gently down. It shouldn’t cause any pain or interfere with your breathing at any time.

During the test some air will pass down the endoscope to distend the stomach. This is done to give the endoscopist a clear view and may cause some temporary discomfort.

When the examination is complete, we’ll remove the endoscope quickly and easily and suck the air out.

Will I have an anaesthetic?

We’ll give you a choice of a throat spray and sedation or just a throat spray.

Sedation is through an intravenous cannula (a small plastic tube put into your vein). It’s a sedative not an anaesthetic and will make most people feel drowsy and relaxed.

Throat spray will numb the back of your throat and help to make it less sensitive.

What are the benefits of gastroscopy?

Viewing the lining of the gullet, stomach and duodenum directly is an excellent way to get a diagnosis of your symptoms, or to reassure you that all is well.

Are there any risks involved?

A gastroscopy is a skilled procedure performed by a trained endoscopist who takes every care to reduce any risks. However, as it’s an invasive procedure it carries the risk of complications. Although these complications happen very rarely, we must make you aware of them.

Perforation or tear of the lining in the bowel of the gastrointestinal tract (a tear in the lining)

It’s extremely rare but serious complication that will mean staying in hospital. This happens to approximately 1 in 2,000 people. The risk is greater if you have a dilatation (stretch) procedure.

Bleeding which is significant in volume (equal to more than a cupful)

This is a rare complication that usually requires admission to hospital. However, a small amount of bleeding isn’t unusual and shouldn’t cause alarm, especially following biopsy. It may happen up to several days after the procedure.

Mechanical damage to teeth or bridgework

We’ll ask you to remove any dentures and insert a mouth guard before the procedure. This will protect your teeth and reduce the risk of you biting the scope.

Risk of a missed lesion

Although this has been chosen as the best test to diagnose your symptoms, no test is perfect. There is a risk of 1 in a 100 that we might miss a large polyp or other important finding during your test.

Risks associated with having sedation

Sedation in a small number of patients may cause problems with slower breathing, low blood pressure and a slow heart rate. Careful monitoring of these vital signs during the procedure by your nurse will detect any changes early. These can be treated rapidly.

Is there an alternative procedure?

A transnasal endoscopy may be appropriate. This involves a thinner endoscope passing through your nose.

Alternatively, a barium meal x-ray examination may show the cause of your symptoms. However, in many cases it’s not as informative as an endoscopy and biopsies can’t be taken.

How long will I need to stay in hospital?

You’ll need to stay in hospital for 2 to 4 hours and so you may need to take time off work.

The unit closes at 6pm. Appointment times are not exact and the unit has to respond to unexpected emergencies. Occasional delays are inevitable.

When will I get the results?

We’ll discuss the results with you before you leave.

What do I need to do before my appointment?

If you’re taking proton pump inhibitors (PPIs)

Stop taking PPIs 2 weeks before your gastroscopy unless this is a follow up procedure. For example, to make sure an ulcer has properly healed.

PPIs include:

  • lansoprazole (Zoton)
  • omeprazole (Losec)
  • esomeprazole (Nexium)
  • pantoprazole (Protium)
  • rabeprazole (Pariet).

If you’re asthmatic bring your inhalers with you and tell the nurse.

If you have diabetes tell the Endoscopy unit. Bring your diabetic tablets and/or insulin with you on the day. If you need advice, contact your diabetes specialist nurse.

If you have sleep apnoea bring your usual breathing apparatus with you for use during the procedure.

If you’re taking iron tablets stop taking them 7 days before the test.

If you’re taking Warfarin or any other blood thinning tablets, tell the Endoscopy team when making your appointment.

Other blood thinning tablets include:

  • Rivoroxaban
  • Dabigatran
  • Apixaban
  • Edoxaban
  • Clopidogrel
  • other ‘antiplatelet’ drugs.

You can continue taking Aspirin.

Is there anything else I need to bring?

Please bring a list of medication with you.

Do not bring valuable items or jewellery.

Preparation for your appointment

If your appointment’s in the morning:

  • do not have anything to eat or drink from midnight of the night before the examination. Food or liquids will obscure the view of the endoscope and the examination will not be possible.
  • you can have a small glass of water no later than 2 hours before your appointment time
  • bring your regular medication with you and you can take it after your procedure.

If your appointment’s in the afternoon:

  • have a light breakfast before 8am. We recommend toast and tea. Do not eat porridge or eggs
  • have your last drink at least 4 hours before your appointment. Avoid milky drinks
  • have a small glass of water no later than 2 hours before your appointment time
  • if you take regular medication in the morning, take it as usual.

What happens when I arrive?

The receptionist will book you in and a member of the Endoscopy nursing team will collect you from the reception area. If you haven’t already been seen for a pre-assessment discussion, we’ll take you to a private room to get a brief medical history.

The nurse will explain the risks involved in the procedure. You’ll have the opportunity to ask questions. You can also sign your consent form if you haven’t already done so.

Family friends and relatives

After the pre-assessment, we’ll ask anyone accompanying you to return to the reception area until after your procedure.

Refreshment facilities are available at:

  • Stoke Mandeville Hospital. There’s a restaurant in the main entrance (entrance 3)
  • Wycombe Hospital. There’s a café within reception at main entrance (ground floor of the main tower block)

After the examination

A doctor or one of the endoscopy nurses will discuss the results of your test with you before to your discharge from hospital.

What are the possible side effects of the procedure?

You’re likely to have a sore throat after the procedure. You may also feel bloated from the air blown in to help the examination.

What are the after-effects of the sedative injection?

Your mental ability to think clearly and make decisions may be affected for up to 24 hours after the procedure, even though you feel wide-awake.

For this reason, you must have someone who can take you home and look after you for the rest of the day. You may resume eating as normal.

For 8 hours after sedation, you must not:

  • use potentially dangerous appliances such as a cooker or kettle
  • have a bath unsupervised
  • look after dependants on your own
  • go to work
  • sign any legal documents
  • drink alcohol
  • take sleeping tablets or recreational drugs.

For 24 hours after sedation, you should not:

  • drive
  • operate potentially dangerous machinery.

Advice and support after your procedure

Call us if you’re worried about any symptoms you experience after this test.

If you have any severe chest or abdominal pain, particularly on swallowing, or if you vomit blood, get help immediately.

During normal office hours

Stoke Mandeville Hospital, 01296 315220

Wycombe Hospital, 01494 425073


Outside office hours

Call Ward 17 at Stoke Mandeville Hospital on 01296 418201.

This is for patients who had their procedure in Wycombe or Stoke Mandeville hospitals.

In an emergency, come directly to Stoke Mandeville Hospital Emergency Department.

Follow up information

You’ll need to:

  • see your GP for treatment. Take a copy of the report with you to your GP appointment
  • have your haemorrhoids banded (removed)
  • have an appointment in our outpatients clinic
  • have another investigation
  • talk to your GP and/or consultant about your biopsy results in approximately 8 weeks. We’ll contact you if further action is necessary.

Useful links

Buckinghamshire Healthcare NHS Trust

British Society of Gastroenterology 

Guts UK Digestive Disorders Information