10
Andover Road
Portland, Maine 04102
207-761-6642
www.cascobaysurgery.com
Esophageal pH Testing
Location:
Date: Time:
Arrival Time:
Goal of the test
To measure the amount of stomach acid flowing backwards (refluxing) into your
esophagus during a 24-48 hour period. This will indicate whether you have an
abnormal amount of reflux and will help determine whether your symptoms are due
to that reflux.
How the test works
The probe detects every time stomach acid enters your esophagus and records the acid level (pH) on a Walkman-size data recording box you will carry with you. The recording box has several buttons on it for you to push when you have heartburn or other symptoms, a meal, or during some other events. Ask the nurse before you leave if you aren't completely clear about how to use the buttons. You will return briefly the next morning to have the probe removed. Within a few days I'll review the amount & timing of your acid reflux and how consistently that reflux coincides with the symptoms you recorded.
Two techniques are available for this study:
 |
Conventional
24-hour pH study: The nurse in the endoscopy department will pass a tiny catheter the size of a
piece of cooked spaghetti down one nostril (after numbing your nose with a spray) and will
have you swallow it down into your esophagus. |
|
Bravo 48-hour pH study: The endoscopist will attach a tiny acid-sensing transmitter to the lining of your esophagus using light sedation and endoscopy. It will transmit data through your body using radio waves, therefore not needing a catheter out your nose. The data recording box must stay within 3 feet of you the entire 48 hour study period. You return the box after 48 hours. The transmitter detaches by itself and passes through your intestine undetected. |
Importance of the exam
I use this test only when I believe it is essential for confirming acid reflux
as the source of your symptoms and making an appropriate decision regarding the usefulness of antireflux
surgery. For that reason anything that affects the accuracy of the test can
cause me to interpret the results incorrectly. These errors can either underestimate or
overestimate the degree of reflux. Although it's not likely I would do
unnecessary surgery, I could very well decide against an operation that would be
beneficial or curative. Usually we can identify a flawed study and simply repeat
it.
Most common problems
1.
Stomach isn't making acid
- This occurs when someone doesn't stop taking their antireflux medication (Prilosec,
Prevacid, Aciphex, Protonix, Pepcid, Zantac, Axid, Tagamet) or doesn't stop taking it
long enough before the test. Put bluntly, I want you to have a bad day, not
because you have a catheter in your nose but because you have a lot of your
usual symptoms. Stop your medication far enough in advance that you will have
symptoms but not so far ahead that you suffer unduly while awaiting the test.
Antacids (Mylanta, Maalox, TUMS, Rolaids, Gaviscon) are okay to take up until
the night before the test because they are very short acting. If your usual
symptoms aren't typical heartburn (such as nausea, chest pain, cough) you
might need to stop your medication a week or more in advance to be sure it
doesn't confuse the test results. Medication use is the most common reason for me
to ask somebody to repeat a test. If you are feeling fine the morning of your exam, call
the office so we can reschedule it for another day. If your symptoms become
unbearable during the night of the test and you must take your medication,
please make a note of what you take and at what time.
2.
Inaccurate symptom recording
- My ability to tell whether your symptoms are due to reflux is only as
accurate as your recording of those symptoms either with the buttons on the
recording box or in a written diary (or, ideally, both). If you don't record the
occurrences and timing of your symptoms very well, I'm more likely to make an
incorrect interpretation that your symptoms aren't due to reflux. That might
keep me from recommending surgery or at least delay you in getting what could be useful
and curative surgery.
3.
Probe position changes
- The catheter either falls out or moves forward into the stomach. I want you to do your usual activities, but be
careful of the catheter and try to protect both it and the tape holding it in
position.
4.
Recording box malfunction
- Occasionally it simply fails, but not often. If only the button function
breaks we can compensate if you've kept a written diary of when you had
symptoms, what symptoms, when you ate, etc.
Don't
leave the Endoscopy Center if you have any questions about what you're supposed
to do during the test. If you have any questions or
problems, please don't hesitate to call us, either
before or during the 24-48 hour test period.
Last updated 5/5/05