Test / Diagnostic Procedure: High Resolution Oesophageal Manometry and Reflux Monitoring

Oesophageal manometry is a test that measures the way the oesophagus (gullet) works by looking at how well food is pushed down to the stomach after swallowing. The reflux test, also known as pH-impedance monitoring, measures the movement of food and fluid in the other direction, from the stomach into the oesophagus. Patients are usually referred for both tests together in order to study why food/fluid sticks or goes down slowly through the oesophagus, as well as to investigate symptoms of heartburn, regurgitation, belching or persistent cough. These tests take place on the 7th Floor of OneWelbeck, in the Digestive Health Centre.

These investigations give the best overall picture of how the oesophagus works and why things can go wrong and lead to symptoms. By doing so, these tests can help to determine the correct treatment plan for you. Also, these tests are a requirement if the treatment being considered includes an anti-reflux procedure for reflux disease or other treatments for swallowing disorders.

In many cases there are two parts to the test, oesophageal manometry, and then pH-impedance monitoring. Your doctor will inform you if you need one or both tests as they measure different things.

During ‘oesophageal manometry’, a thin tube is passed gently from the nose to the stomach as you sip some water. Gel is used to help insert the tube and a local anaesthetic spray or gel may be used to numb the nose. The process takes around 15 minutes, after which the tube is gently removed.

The pH-impedance study is the second part of the test. A much finer tube is gently passed in the same way, from your nose, down your oesophagus and into the stomach. It is then secured to the side of your face and neck with tape. The tube is attached to a small recorder which you wear over your shoulder or on your belt, and you will be asked to press buttons to record information such as eating, sleeping and symptoms when they occur. This tube stays in place for 24 hours. You can then easily remove it yourself the next day (we will explain how) or you can come back to the clinic for it to be removed by the nurse. Everything will be discussed with you fully before you sign the consent form.

You might have manometry without the pH study, but manometry is always undertaken before the pH-Impedance study, even if you have no swallowing problems, as the appropriate position to place the pH sensor needs to be determined.

Once the 24 hours are over you will return to the clinic to bring back your recorder and a diary which you will have been asked to complete. The study cannot be completed until the recorder is returned and the information downloaded.

Patients can sometimes experience a brief period of retching when the tube is inserted down the throat and there may sometimes be some discomfort in the nose and throat, but usually this is well tolerated and lasts for a very short time. Very occasionally, a small amount of bleeding from the nose can occur but this tends to stop very quickly. Occasionally, patients describe a sore throat after the procedure, but again this is short-lasting. Almost always these symptoms are temporary and stop as soon as the tube is taken out or shortly after the procedure. If at any point you are not comfortable or wish for the study to stop, the catheter will be removed immediately.

Although the environment and the equipment are cleaned under strict guidelines, there is always a very small risk of acquiring Covid from visiting the centre.

With regards to the swallowing study, a Barium swallow can be used instead of oesophageal manometry, but this only offers a snapshot and does not provide the same information as manometry which measures true eating and drinking.

With regards to the reflux test, the alternative for the catheter-based pH-Impedance study is a wireless pH study, which involves stitching a pH sensor into the bottom of the oesophagus during endoscopy. Wireless pH monitoring and the catheter-based reflux testing each have their advantages and disadvantages, please speak to the doctor who referred you to determine which is more appropriate.