Advice after your nerve block for surgery
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What is an Endoscopic Mucosal Resection (EMR)?
What is a HALO radiofrequency ablation (RFA)?
Occasionally patients with Barrett’s Oesophagus can have small nodules that need to be removed, usually before HALO therapy can begin. This is when the nodule is removed or resected at the time of the gastroscopy.
RFA is the name given to a procedure when a device is passed down the oesophagus and energy is applied to the lining of the oesophagus that contains the abnormal cells (dysplasia). It is performed much like the endoscopy procedures you have already undergone.
What is dysplasia of the oesophagus?
Dysplasia is a term used to describe cells that line the oesophagus that look abnormal when examined under a microscope. It commonly occurs in patients with Barrett’s Oesophagus. Barrett’s Oesophagus is a condition that is associated with excess acid production and gastro-oesophageal reflux disease. Barrett’s oesophagus with dysplasia is considered a pre-cancerous condition and has two forms – low grade dysplasia and high-grade dysplasia.
What does the procedure involve?
A long, thin flexible tube called a gastroscope is used. This is slightly thinner than your little finger and has a camera on its tip which sends pictures of the inside of your stomach and intestine to a video screen.
A gastroscope is first passed down to the oesophagus to carefully examine the area that needs to be treated. This assessment allows the opportunity for the doctor to work out whether any additional procedures might be necessary before you can start your HALO treatment. Occasionally, additional procedures such as an EMR or balloon dilatation of a narrowed oesophagus or stricture are needed.
Following this assessment the doctor will then carry out the therapy. The assessment also enables the doctor to work out which size device will be used during your treatment. These devices are passed down your oesophagus and are no different to an endoscope.
What are the options and alternatives for treating dysplasia?
If you have been found to have low grade dysplasia you will be monitored in the first instance with a repeat endoscopy 3 – 6 months apart. If the low grade dysplasia is still present after a couple of examinations, then we would consider offering you HALO RFA. If you have been found to have high grade dysplasia, then you will be offered HALO RFA.
When diagnosed with dysplasia of your oesophagus the options available would include:
1. Repeated endoscopies to observe the dysplasia in the oesophagus and if a cancer develops this can be detected at an early stage when it can be successfully treated.
2. Endoscopic treatment such as an Endosocopic Mucosal Resection or EMR or HALO RFA.
3. Surgery to remove your oesophagus (oesophagectomy). This is a very major operation.
What are the benefits?
The benefits include the treatment of the abnormal cells in the lining of your oesophagus and preventing you from developing cancer and the need for major surgery.
What are the risks?
You may experience some mild temporary chest discomfort or difficulty in swallowing. This will settle in a few days. Serious complications of Gastroscopy and EMR or HALO are rare. They include:
- Stricture: A stricture, or narrowing of the gullet may occur in less than 1 in 20 cases. This can be treated by stretching the narrowed area with a gastroscopy and a special balloon.
- Bleeding: Bleeding occurs in less than 1 in 1,00 cases.
- Perforation: There is a small risk of causing a tear (perforation) in the oesophagus during the procedure — this happens in about 3 out of every 1,000 cases. If a perforation does happen, it can be serious and may require emergency treatment, including surgery. In very rare cases this could be life threatening.
- Missed lesions: There is a small risk that abnormalities such polyps or other lesions may not be visible or detected during the procedure.
Will I need sedation?
We recommend that patients have sedation for this procedure. For this procedure you are given propofol sedation (deep sedation) which is administered via a cannula (small plastic tube). Occasionally, patients who are nearing the end of their treatment plan will be offered the procedure with standard sedation, but this would be discussed with you first.
Someone must come to collect you and stay with you overnight. You will not be allowed to go home on your own in a taxi. If you cannot arrange this, we would have to cancel your procedure.
What are the risks of having a sedative?
You may feel tired, dizzy or weak straight afterwards. During the first 24 hours you must not: drive a car, operate machinery, drink alcohol, take sleeping tablets, sign legal documents, look after young children and/or dependants alone.
Do I need to stop taking my medication?
If you take blood thinning medication, you may need to stop taking them for a short time. If you have not been advised whether you need to stop or continue to take them, please contact us on 0300 613 6045, between 8:00am and 1:00pm, Monday – Friday.
If you are diabetic, please read our advice sheet.
If you have not received this, please ring the booking office on 0300 613 6647 / 0300 613 4858, between 9:00am and 5:00pm, Monday – Friday and we will send you a copy.
In general you can take your medications as usual, unless your doctor has advised you otherwise.
Do I need to prepare for my test?
• We need to get a clear view, so your stomach must be empty.
• Do not eat anything for six hours.
• You can have clear fluids such as water or black tea up to three hours before the procedure.
What happens when I arrive for my test?
Please note that your appointment time is the time that you should arrive in the department. It is not the time of your actual procedure. We recommend that you plan to be with us for the whole morning.
When you arrive, a nurse will fill out an assessment form with you and ask you about your arrangements for getting home. Someone must come to the endoscopy unit, collect you and stay with you overnight. You will not be allowed to go home on your own in a taxi.
The nurse will check your temperature, blood pressure, pulse, respiration rate and your oxygen levels. If applicable, the nurse will check your INR and blood sugar levels. A nurse will put a cannula (small plastic tube) into a vein, usually on the back of your hand, through which the endoscopist will administer the sedation. You will be asked to take your top off and put on a hospital gown. There are single changing cubicles available in the unit.
Consent
We must obtain your written consent to any procedures by law beforehand. We want to involve you in decisions about your care and treatment. The endoscopist will explain all the risks, benefits and alternatives. If you decide to go ahead, we will ask you to sign a consent form.
In addition, where necessary, an Anaesthetist will explain all the risks and benefits of propofol and if you decide to go ahead, will ask you to sign an anaesthetic consent form as well.
If you are unsure about any aspect of the treatment proposed, please do not hesitate to speak with a member of staff.
What happens before the test?
You will be looked after in the procedure room by doctors and nurses, depending on what needs to be done. There may be a trainee who observes the procedure. If so, we will ask your permission for this. You will be taken into the endoscopy room and make you comfortable on an examination couch. We will monitor your blood pressure, pulse, respiration rate and your oxygen levels during the test.
We will ask you to lie down on your left side. We will put a mouthguard in your mouth and ask you to bite gently on it. This makes it easier for the endoscope to be passed down your throat.
You will be given sedative medication just before the start of the test. Oxygen will be given through a sponge placed in your nostril.
What happens during the test?
The team in the procedure room will reassure you and clear saliva (spit) from your mouth using suction. The doctor will view images of your oesophagus, stomach and the upper part of your small intestine on a screen and go onto perform the therapy as described above. Medical photographs are taken during the procedure for the report.
How long does the procedure take? What happens after the test?
This depends on the amount that we are treating. It usually takes approximately 30 minutes. Patients with morning appointments should be ready to be discharged from the unit between 11.00am and 1.00pm.
Because you have had a sedation, you will need to stay until this has worn off. This usually takes at least 30 – 45 minutes. A nurse will give you any necessary paperwork before you leave the department. We will also send a copy of the report to your GP and the hospital specialist.
What happens when I go home?
After the procedure you will need to alter your diet for about 7 days. In the first 24 hours you should drink liquids only.
2 hours after the procedure, start by taking sips of cool fluids for 4 hours. After this time, you could have smooth soups, yoghurts and ice creams. These liquids should not be too hot or too cold, about room temperature.
When 24 hours pass after your procedure, you can then start on a sloppy diet. This includes soft porridge, thicker soups, and minced meat with gravy. Over the next 7 days you can slowly introduce more normal foods.
After an EMR or HALO you may notice some effects for up to 14 days. These effects consist of mild chest discomfort (like heartburn), and some mild discomfort when you eat food. Paracetamol is usually sufficient to treat this.
Please contact the endoscopy department if you experience any of the following: fever, great difficulty in breathing, severe chest pain, abdominal pain, difficulty swallowing, bleeding.
Medications to take home?
You will be discharged home with some medications to help heal the oesophagus. These will include some antacids and some paracetamol.
You can take all your other medications as normal unless you think that they are particularly large tablets. If this is the case, then please let your doctor know and we can prescribe an alternative.
If you take medications that thin the blood you can restart them the day after the procedure unless advised otherwise.
Important Notice for Patients on Weight Loss Injections (Mounjaro, Wegovy or Ozempic)
If you are currently receiving weight loss injections, please stop this treatment one week prior to your scheduled endoscopy procedure.
For any questions or concerns, please contact the Endoscopy Nursing Team:
• Frimley Park Hospital: 0300 613 6045
• Wexham Park Hospital: 0300 615 4163
What should I bring with me to hospital?
- the name and contact number of the person collecting you
- a list of medications including herbal and over the counter medications
- a list of allergies to medication, food or substances
- please bring your essential medications such as insulin, Parkinsons medication, epilepsy medications, etc.
Please do not bring any valuables with you. The hospital cannot accept responsibility for the loss or damage to personal property during your stay in endoscopy.
Who can I contact with queries and concerns?
For medication queries before or after your test, please contact the Endoscopy Unit Nurses’ Station at Frimley Park: Tel: 0300 613 6045, between 8.00am and 1.00pm, Monday - Friday.
If you want to change your appointment or need another information leaflet, please contact the Endoscopy Unit booking team:
Tel: 0300 613 6647/ 0300 613 4858 9.00am – 5.00pm, Monday – Friday.
Contact us
If you have any queries relating to this information, please contact the Endoscopy service.
About this information
Service:
Endoscopy
Reference:
H/091
Approval date:
1 September 2025
Review date:
1 September 2028
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Important note
This page provides general information only. It is developed by clinical staff and is reviewed regularly every 3 years for accuracy. For personal advice about your health, or if you have any concerns, please speak to your doctor.