Twenty-four-hour ambulatory oesophageal pH monitoring: experience in The Netherlands
Klinkenberg-Knol, E.C.; Ogilvie, A.C.; Meuwissen, S.G.
Netherlands Journal of Medicine 34(Suppl): S40-S54
1989
ISSN/ISBN: 0300-2977 PMID: 2657460 Document Number: 345926
Twenty-four-hour ambulatory oesophageal pH monitoring has become a major diagnostic method for the valuation of gastro-oesophageal reflux disease. Essential requirements for registration and reproduction of the pH are reliable pH electrodes, well-performed calibration and optimal and reproduction and analysis of the signal. The most commonly used pH probes in the Netherlands are not-combined monocrystal line antimony electrodes (Ingold and Radiometer). For diagnostic intra-oesophageal pH measurements both types are suitable; for research purposes, especially intragastric, glass electrodes are preferable. In The Netherlands several types of solid-state recorders are commercially available: all fulfill the conditions necessary to produce reliable registrations. In the present study, available measuring systems in The Netherlands and current practices associated with ambulatory pH monitoring were evaluated. Inquiry among the Dutch pH registration centres showed that more than half were using Synectics electrodes and equipment. Positioning of the pH probe was based on manometry (25%), fluoroscopy (22%) or endoscopy (20%). In the initial phase there were many problems, especially related to ignorance of the complicated registration procedure. For ambulatory pH measurements we recommend a simple datalogger with a sufficient memory capacity and direct interface with a PC, a combined glass electrode positioned 5 cm above the manometrically determined lower oesophageal sphincter. For clinical interpretation of the result the percentage of time with pH below 4 is probably the most reliable parameter for the detection of pathological gastro-oesophageal reflux.