This test measures the pressure inside the gullet and in the valves at each end of it, to see whether the swallowing muscles are working and coordinating properly. It is a short test, it needs no sedation, and almost everyone tolerates it.

What it is, and why you are having it

Swallowing is a coordinated wave of muscle squeeze that carries food from the throat to the stomach, with a valve at the bottom that must relax at the right moment to let food through. A camera test shows what the gullet looks like, but not how it moves. Manometry measures the movement.

It is done for difficulty swallowing that has not been explained by endoscopy, for unexplained chest pain once the heart has been checked, and when achalasia is suspected — before any treatment for it is planned. It is also required before anti-reflux surgery, to make sure the diagnosis is right and the gullet squeezes well enough to cope with the operation.

Manometry does not diagnose acid reflux. If you also need a 24-hour acid measurement, the manometry is normally done first, because it shows exactly where to place the acid sensor.

1 the fine tube passed through the nose · 2 the pressure sensors along it · 3 the upper valve · 4 the lower valve · 5 stomach

Getting ready

• Have nothing to eat from midnight the night before. You may take small sips of water until two hours before the test.
• Medicines that change how the gullet moves must be stopped 48 hours before, if it is safe for you to stop them: nitrates, calcium-channel blockers such as nifedipine, amlodipine or diltiazem, opioid painkillers, anticholinergic medicines, and prokinetics such as metoclopramide or domperidone. Do not stop a heart or blood-pressure medicine on your own — telephone the endoscopy unit, or the doctor who prescribed it, for advice on what to do.
• Take your other regular medicines as usual. If you take insulin or tablets for diabetes, telephone the endoscopy unit before the appointment so the dose can be adjusted around the fast.
• You do not need to stop acid-reducing tablets for manometry alone. You do need to stop them for a pH study — see sheet PE-PROC-14 — so if both tests are planned, follow the instructions for the pH study.
• Tell the endoscopy unit if you have had nose or throat surgery, if you have significant nasal blockage, or if you have varices in the gullet.

On the day

No sedation is used, and no sedation is needed. A very thin flexible tube is passed through one nostril and down into the gullet. Passing the tube is the uncomfortable part; it takes a short time and most people find it easier than they expected. You will be asked to sip water and swallow as it goes down.

Once the tube is in place you lie down. You will be asked to swallow a small measured amount of water about ten times, with a pause between each swallow while the machine records. You are then usually asked to sit up and repeat some of the swallows, to take several sips in quick succession, and to drink a glass of water straight down — each of these tests the gullet in a different way. The recording takes about ten to fifteen minutes in all. The tube is then removed, which takes a second.

What are the risks?

There are essentially no risks. Some people find the tube passing through the nose uncomfortable, and some gag briefly, but this is mild and short-lived. A little nosebleed or a sore throat afterwards is possible and settles on its own.

Afterwards

You can go back to normal life immediately — eat, drink, drive and return to work. There is nothing to avoid.

The recording has to be analysed before it means anything, so the result is not given on the day. It goes to the doctor who requested the test and is discussed at your clinic appointment.

This leaflet is general information and does not replace advice from your own doctor.