Esophageal pH Study for Acid Reflux and Non-acid Reflux

What is the pH study for acid reflux and non-acid reflux?

A 24- or 48-hour (Bravo) esophageal pH study measures how much stomach acid backs up into the food pipe in 24 or 48 hours, respectively. The most common uses for this gold standard test are: to diagnose GERD (gastroesophageal reflux disease), a feeling of heartburn, pain and food coming back up, or to diagnose patients with atypical chest pain, recurring pneumonia or throat symptoms.

How do you prepare for the study?

Do not eat or drink anything after midnight on the evening before the surgery. (If you are diabetic, please discuss this requirement with your primary care doctor.) You may, however, take scheduled medications with small sips of water up until two hours before the study. You should also refrain from taking any antacids (Zantac®, Prevacid®, Prilosec®, etc.) for the 72 hours immediately prior to the procedure, unless advised otherwise by your doctor.

What should you expect on the day of your study?

For the 24-hour esophageal pH study, a technician places a catheter into your nose, guides it into your stomach and secures it. The procedure takes about 30-45 minutes, and the patient is not sedated. The catheter is then left in your stomach for 24 hours. After the procedure is complete, patients will receive instructions on how to measure their daily activities.

The 48-hour (Bravo) esophageal pH study is combined with the upper endoscopy procedure.

After you check in, one of our nurses will meet with you to review your medical conditions and medications. An IV line will be placed in a vein in your arm. You will proceed to the procedure room, where your blood pressure, pulse and oxygen level will be carefully monitored. A sedative will also be administered through your IV. You will soon feel drowsy, and while some people fall asleep, others remain awake during the procedure. A small capsule will be clipped to the lower part of the esophagus and then you will have to rest for a while until the effects of the medicine wear off. The test itself usually takes less than an hour.

You will not be able to drive following the procedure, so plan on having someone with you to take you home. Before leaving, our staff will speak with you about the preliminary results of your test and will let you know when you can go back to eating your regular diet. You also will be given a small monitoring device, which you will need to return in 48 hours.

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