Background: Use of a catheter-free, radio telemetric, oesophageal pH-monitoring system in paediatric clinical practice allows patients to follow a more normal physiological pattern of activities and causes less discomfort. At our institution, placement of the capsule is done under general anaesthesia, which restricts the child's activity during the first day. The aim of this study was to determine whether oesophageal pH-measurements should be performed over 48 hours or whether 24-hour measurement provides sufficient and reliable results.
Children and methods: The study included 24 consecutive children with symptomatic gastro-oesophageal reflux problems who had undergone upper gastrointestinal endoscopies under general anaesthesia. The radio-transmitting Bravo capsule was introduced transorally and placed above the diaphragm at a width of two vertebral bodies. Oesophageal acid exposure was monitored via a portable receiver for 48 hours. The children's symptoms during measurements were registered. Wilcoxon signed rank test for paired samples was used after power analysis.
Results: The capsule was successfully attached to the oesophageal mucosa in all cases with minor technical problems in only one patient. The 48-hour pH-monitoring was completed in 23 patients. The median percentage time with an oesophageal pH of less than 4 was 5.4 +/- 6.8 for the first 24 hours and 5.8 +/- 7.4 for the 48-hour measurement. The DeMeester score was 20.5 +/- 23.7 and 22.2 +/- 25.7, respectively.
Conclusions: Ambulatory pH-monitoring using the wireless system is feasible and safe. It was well-tolerated by the children. There was no statistical difference between the pH-measurements or DeMeester scores during the first 24 hours compared with the 48-hour measurements. Individual variations were noted but had no clinical significance except in two patients. Our results support the use of pH-measurement for a period of 24 hours only.