The 24 hour monitoring measures the amount of acid and duration of acid exposure in your oesophagus over a 24 hour period. A small pH probe is inserted through the nose and sits a few centimeters above the lower oesophageal sphincter. Acid reflux is recorded whenever the pH drops below pH 4 (water pH 7, normal oesophagus pH 6). This test will tell us how much acid reflux you experience and when these events are occurring (e.g. after meals or during sleep).
Preparation for 24 hr pH monitoring study
- Drugs such as Nexium, Pariet, Losec, Somac, Zantac, Pepcidine, Amfamox, Tagamet, Acimax, and Tazac must be stopped 3 days prior to your appointment for the 24 hr pH test.
- Continue all other forms of medication as prescribed
- Stop eating and drinking 4 hours prior to the test
- The studies are considered painless but, lignocaine spray is used to numb the nose and back of the throat
- The time required for each appointment is approximately 1 hour
- The 24 hr equipment (computer pack, catheter and journal) must be returned the following day
A soft plastic probe is passed gently through the nasal passage and swallowed easily into the oesophagus, stopping about 5 cm from the stomach. The probe is then secured in place to your nose, cheek and back of the ear with clear tape.
The probe is then plugged into a small, lightweight portable computer pack which can be worn over your shoulder for the 24 hours.
24 hr pH monitoring is the gold-standard diagnostic test for gastroesophageal reflux disease. We also have 24hr impedance and pH monitoring. This probe contains the standard pH sensor in addition to impedance sensors which measure non-acidic reflux (e.g. water brash) and a proximal pH sensor to detect laryngopharyngeal reflux.
Patients are sent home with the catheter in place and are encouraged to proceed with their normal daily activities. For example: eating, drinking etc. Patients will monitor and document their activities (medication, meals, and sleep) and symptoms on the monitor device and a diary.
Upon completion of the 24 hour monitoring period, the patient returns to the clinic the following day and the catheter is removed by the clinical nurse. The data collected from the monitor and the journal will be analysed.
| Manoeuvre | What are you asked to do? | What are we measuring? |
|---|---|---|
| Meals | Record time and duration of eating by pressing the "meals button", also write down the types of food or portions in the diary | Incidences of reflux during and after meals |
| Medication | Record medication usage by pressing the "pill button", also write down the type of medication and dosage in the diary | Effects of your medications on acid reflux |
| Symptoms | Record symptom event and type (e.g. cough, heartburn) by pressing the "symptom button", also write down the symptom in the diary | Determine association between reflux events with specific symptoms |
| Sleep | Record sleep time by pressing the "supine button" before you lie down to bed and after you wake up | Evaluate reflux events during sleep |