Oesophageal Manometry

When food enters the stomach, strong acid production begins for digestion. The sphincter mechanism at the point where the gullet (the oesophagus) enters the stomach works like a one-way valve and prevents the stomach’s acid escaping into the oesophagus. Sometimes this mechanism does not work well, and the stomach’s acid, bile and contents escape into the oesophagus and cause the complaints of reflux.

However much the oesophagus may look like a hollow tube that carries the food we eat down to the stomach, one of its important functions is peristalsis. These movements, like waves at sea, keep pushing what is inside the oesophagus onwards towards the stomach. If these movements are too strong the patient has chest pain; if they are too weak, or not coordinated, difficulty in swallowing develops.

Surgery for reflux

Generally most patients respond well to changes of habit and to drugs. If the reflux is at a level that is very troublesome and began at an early age, surgical reconstruction of the lower oesophageal sphincter is considered as an alternative method of treatment. With the older kinds of surgery a stay of six weeks in hospital was in question. With this new procedure, called laparoscopic Nissen fundoplication, the stay in hospital and the time to recovery have become considerably shorter. The decision to operate will be made after examination, radiological investigation, oesophageal pH measurement and manometry.

The oesophageal manometry test

Manometry is a test that measures the pressures of the muscle inside an organ. Oesophageal manometry measures the pressure and the coordination of the wave of peristalsis inside the oesophagus, and also measures the pressure of the sphincter mechanism at the lower end of the oesophagus (the LES pressure). For this purpose a tube-shaped instrument containing pressure sensors is used. When the oesophagus begins to contract during eating, the pressures begin to be measured; they are recorded on a recording device and assessed by your doctor. If the pressure in the lower oesophagus is strong enough, surgical treatment is not considered for the patient.

The oesophageal pH test

The oesophageal pH test measures how often acid refluxes from the stomach down into the lower gullet. For this procedure a thin, flexible plastic tube with a pH probe at its tip is passed through the nose towards the stomach, and the end of this probe is connected to a recording device worn on a belt at the waist. The reflux of acid from the stomach into the lower oesophagus is recorded over 24 hours. When the complaint of reflux begins, or when there is chest pain, a button on the recorder is pressed, and the relationship between the onset of the symptoms and the acid pH being measured is observed. The records are then gathered on a computer and analysed.

Preparing for the procedure

The patient should go without food for about eight hours for this procedure; a little water may be drunk. For 72 hours before coming for this test, the following should not be used: caffeine (coffee, tea, cola, chocolate), alcohol, ulcer drugs (Tagamet, Axid, Zantac, cimetidine, Lansor, Aprazol and the like), anticholinergic drugs (Librax, Baralgin), erythromycin, nitroglycerine, Isordil, calcium channel blockers (Adalat, Nidilat, Diltiazem, Isoptin and the like) and beta blockers (Dideral, Visken, Tenormin).

How the test is done

The manometry test takes about an hour; there may be retching while the instrument is being placed, and you may be asked to drink a little water or to swallow so that it can pass down. Placing the oesophageal pH instrument through the nose down to the lower oesophageal sphincter can take ten minutes. Once the instrument is in place it is fixed with tape to the nose and behind the ear. For this reason you should plan your social activities around it beforehand. After this procedure the patient may have a slight sore throat.