Oesophageal pH Monitoring and Manometry

What are oesophageal pH monitoring and manometry?

Oesophageal manometry and 24-hour pH monitoring are specialised tests used to assess how the oesophagus functions.

• Oesophageal manometry assesses the contractions of the oesophageal muscles and the function of the lower oesophageal sphincter. It helps diagnose swallowing problems and oesophageal motility disorders, such as achalasia, and is also important before certain anti-reflux operations.
• 24-hour pH monitoring, sometimes combined with impedance monitoring, determines whether acidic or non-acidic stomach contents enter the oesophagus. It assesses the frequency of reflux episodes and their association with the symptoms experienced by the patient.

Both tests involve passing a thin, flexible probe through the nose and into the oesophagus. The tests are safe and an anaesthetic is not usually required.

How should I prepare for oesophageal pH monitoring and manometry?

• Do not eat for at least 6 hours or drink for 2–4 hours before the test.
• Take essential medicines only as instructed by your doctor.
• Before pH monitoring, acid-suppressing medicines are usually stopped as follows:
  • proton pump inhibitors, such as omeprazole, pantoprazole and esomeprazole – 5–7 days beforehand. The required period may vary depending on the healthcare provider and the purpose of the test. Follow the instructions provided by the doctor carrying out your test;
  • H₂-receptor antagonists – 48 hours beforehand;
  • antacids and alginates – 24 hours beforehand.
• In some cases, your doctor may instruct you to continue taking acid-suppressing medicines if the purpose of the test is to assess how well the treatment is working.

What happens during the tests?

Oesophageal manometry

• The test takes approximately 15–30 minutes.
• During the test, you will be asked to swallow a small amount of water several times as instructed by the doctor.

24-hour pH monitoring

• The probe remains in the oesophagus for 24 hours. Alternatively, a wireless capsule may be used if this method is available at the healthcare facility.
• During the monitoring period, you should follow your normal routine – eating, drinking and carrying out your usual daily activities.
• It is very important to keep a diary of your symptoms and activities, recording meal times, periods spent lying down, sleep and symptoms such as heartburn, chest pain, belching or coughing. This allows symptoms to be accurately linked to episodes of reflux.

After the tests

• After oesophageal manometry, you may return to your usual activities immediately.
• After 24-hour pH monitoring, the probe is removed at the healthcare facility. The doctor will then assess the collected data and discuss the results with you.