Esophageal pH monitoring is performed if you are having problems with your upper digestive tract. It helps your doctor determine if stomach acid is entering the esophagus.
The esophagus is the muscular tube that connects your throat to your stomach. It is lined with a soft mucous membrane. The membrane protects it from damage.
The esophagus plays a very simple role in the digestive process. It conveys food from the throat to the stomach. This is the very start of your digestive system. Therefore, it is frequently exposed to sharp or abrasive food items like:
- shards of bone
- tough plant leaves
- potato chips
You doctor may recommend this test if you have symptoms of GERD (gastroesophageal reflux disease). The test measures how often and for what length of time acid enters the esophagus.
GERD is a chronic disease of the digestive system caused by bile or acid backing up from your stomach. This causes the following symptoms:
- heartburn (acid indigestion in your stomach, chest, or abdomen)
- regurgitation (discomfort from acid backing up into your throat or mouth)
- dyspepsia (burping, bloating, or nausea after eating)
Many people experience these symptoms from time to time. GERD may be suspected if you are experiencing them more than twice each week. Your doctor may also want to test you if symptoms are so severe that they interfere with your daily life.
This test may be performed in combination with an endoscopy of the upper gastrointestinal (GI) tract. Endoscopy inserts a camera into your esophagus to look for causes of GERD.
In infants, this test can also be used to check for digestive disorders that could cause excessive crying.
Your doctor will pass a fine tube down your throat into your esophagus. At the end of the tube is a tiny pH meter. It calculates the amount of acid present.
You will return home with the tube in place. For the next 24 hours, you will make notes of:
- what time you eat and drink
- what food you eat and drink
- what time you lie down or get up
- any symptoms you experience
The following day, you will return to the hospital to have the tube removed. Data from the device will be combined with your notes to make a diagnosis.
Children are usually required to stay in hospital for the whole 24 hours.
An abnormal result means there is too much acid in your esophagus. This could be related to:
- scars in the esophageal lining
- dysphagia (difficulty swallowing)
- Barrett’s esophagus (damaged cells in the lower esophagus)
- reflux esophagitis (inflammation of the esophagus)
If your doctor suspects esophagitis, you may need additional tests. These might include a GI endoscopy or barium swallow.
There are no significant risks related to this test. Rare complications include:
- inhaling vomit, if the tube causes vomiting
- an irregular heartbeat during tube insertion
You doctor will ask you to avoid eating or drinking for 12 hours before the test. You will also need to stop smoking during this time.
Some prescription medications can affect the results of testing, Therefore, your doctor may tell you to stop taking them for up to two weeks before the test. Some drugs that affect the test include:
- anticholinergics (drugs used in the treatment of spastic GI tract disorders)
- cholinergics (drugs that produce the same effects as the parasympathetic nervous system)
- corticosteroids (steroid hormones)
- H2 blockers (drugs used to block histamine effects on the stomach)
- proton pump inhibitors (drugs used to reduce gastric acid production)
Only stop taking medications if your doctor advises you to do so.
Many people are able to manage the discomfort of heartburn by:
- making changes to their diet
- getting more exercise
- stopping smoking
- reducing caffeine and alcohol consumption
- taking over-the-counter medications
If you have GERD, these solutions may offer only temporary relief. Your doctor may recommend prescription medications to control your symptoms.
Surgery may sometimes be recommended if your GERD is caused by structural damage to your esophagus. The sphincter that closes the bottom of the esophagus may need to be repaired. Surgery can also be used to scar the esophagus so that it no longer feels pain.