Transnasal endoscopy (TNE): what it is, what to expect and the risks

A transnasal endoscopy (TNE) is an investigation that allows doctors or specially trained nurses to look directly at your gullet (oesophagus), stomach and the upper part of the intestine (duodenum). West Hertfordshire Teaching Hospitals NHS Trust describes a long, thin, flexible camera that is passed through your nose, down the back of your throat and into your stomach. If necessary, small tissue samples (biopsies) can be taken for laboratory analysis.

The NHS describes gastroscopy generally as a test in which a thin, flexible tube with a small camera goes into your mouth, or nose, and down your throat into your stomach. TNE is the nose route of that same family of tests. You may see it described as an unsedated endoscopy or as a gastroscopy through the nose.

The NHS lists reasons for a gastroscopy that also apply to TNE: to check what is causing digestive symptoms such as indigestion, difficulty swallowing, stomach pain, black and sticky poo or vomiting blood, to treat some problems, and to check for some types of cancer such as stomach or oesophageal cancer.

United Lincolnshire Hospitals adds that TNE can be done as a follow-up check for certain conditions affecting the stomach or oesophagus, and where a scan or X-ray has shown something that needs a closer look.

West Hertfordshire lists the advantages as follows: the experience is more relaxed and gagging is much less common, you can talk to the endoscopist during the procedure, less time is needed to recover, and because no sedation is used you can drive home and carry on with your day. Lincolnshire notes that sedation is not usually needed but is an option if desired, in which case you need someone to accompany you home and should not drive for 24 hours.

Where a larger tissue sample is needed, a gastroscopy through the mouth may be preferred. Lincolnshire says a gastroscopy is an alternative that is usually offered with sedation, and sometimes needed if larger biopsies are required.

You must follow the instructions in the letter or leaflet from your own hospital, because they differ between trusts. Lincolnshire says not to eat for at least 6 hours before the test and to have only small amounts of water up to 2 hours before; West Hertfordshire gives time-of-day rules for morning and afternoon appointments. If instructions are not followed the procedure may have to be rearranged.

Tell the department about blood-thinning medicines. West Hertfordshire lists warfarin, clopidogrel, ticagrelor, dabigatran, rivaroxaban and apixaban and asks you to notify the department; Lincolnshire gives individual advice for each, and says people with diabetes controlled with insulin or tablets should tell the booking team and follow separate guidance. Lincolnshire says it is sometimes useful to stop acid-reducing tablets for the 2 weeks before, but to continue them if that is difficult or if you are having a follow-up check of an ulcer or Barrett’s oesophagus. Always follow your own unit’s letter.

You will speak with a nurse who will ask about your health and medicines and complete a consent form. Lincolnshire explains that a decongestant, with or without local anaesthetic, is put into the nose, and a local anaesthetic spray makes the nose, tongue and throat feel numb, similar to a dental injection. You sit up or lie on your left-hand side with a probe on your finger to monitor oxygen levels, and a small suction tube clears saliva.

The scope is passed through one nostril and down the throat, and you can talk to the endoscopist. Afterwards you wait for the numbness to wear off before eating or drinking, which Lincolnshire gives as about an hour. West Hertfordshire says you will talk to staff after the procedure and be given a copy of the report.

TNE is generally straightforward and safe, but it is an invasive procedure. West Hertfordshire lists slight nose or throat pain that settles after a few hours and nosebleeds in about 1 in 20 people, most of which stop without treatment. Rare serious complications include a small leak or perforation.

Lincolnshire gives a perforation or tear of about 1 for every 2000 cases, which may need an operation, and bleeding after a biopsy, which usually stops on its own. It also states that there is a small chance that a cancer may not be seen, and that in extremely rare cases the procedure can lead to death, which current evidence suggests may happen in around 1 in every 10,000 examinations.

You may be told what was seen straight away. The NHS says that if a biopsy was taken it can take up to 2 months to get results, and if doctors think you may have cancer you will usually get results within 2 weeks.

After an endoscopy, the NHS says to call 111, or the hospital, if you have a high temperature or feel hot, cold or shivery, or poo that is dark or black like tar. Call 999 or go to A&E if you keep being sick, vomit blood, are short of breath, or have severe stomach or chest pain that gets worse. West Hertfordshire adds severe chest or tummy pain, swelling in the neck or shortness of breath as reasons to attend A&E, and says not to drive yourself.