Page 81 - Effects and Efficacy of (Laparoscopic) Gastrostomy Placement in Children - Josephine Franken

GER symptom questionnaires
For symptom evaluation of GER in children, an age-specific reflux questionnaire was used: the GER Symptom Questionnaire (GSQ). 19 In infants, symptoms assessed were back arching, choking or gagging, hiccups, irritability, refusal to feed and vomiting or regurgitation. In young children, symptoms assessed were abdominal pain, burping or belching, choking when eating, difficulty swallowing, refusal to eat, vomiting and regurgitation. In this questionnaire parents scored the symptoms of their child on a frequency scale (0–7 days a week) and a severity scale (0–7). Patients with at least daily and moderately severe symptoms, or at least weakly and severe symptoms were considered positive for GER symptoms.
24-hour MII-pH monitoring
Ambulatory 24-hour MII-pH monitoring was performed after 72-hour cessation of acid- suppressing medication or prokinetic medication. A single-use multichannel intraluminal impedance pH-catheter (Unisensor AG, Attikon, Switzerland) was calibrated using pH 4.0 and pH 7.0 buffer solutions and positioned transnasally into the distal esophagus with the probe located proximal to the lower esophageal sphincter (LES). Correct catheter position was confirmed with thoracic X-ray. This catheter has a single antimony pH electrode and six ring electrodes for recording of impedance signals, located at 3, 5, 7, 9, 11 and 13 cm from the distal tip of the probe for children below the age of 8 and at 3, 5, 7, 9, 15 and 17 cm for children above the age of 8. For a 24-hour period, acidity and impedance signals were recorded in a digital ambulatory recorder, using a sampling frequency of 50 Hz. Mealtimes, symptoms, body position (supine and upright) and other relevant events (e.g. correction of the catheter position) were documented in a symptom diary.
24-hour MII-pH monitoring: data analysis
Analysis was performed with software designed for MII-pH impedance analysis (Medical Measurements Systems, Enschede, the Netherlands). Meals were excluded from the analysis.
Automated analysis of pH tracings resulted in the following values, all representing traditional reflux measurements: total 24-hour esophageal acid exposure time (defined as the total time with pH below 4 divided by the time of monitoring), number of reflux episodes with pH below 4, number of reflux episodes lasting longer than 5 minutes, longest reflux episode and lowest pH value.
Pathological esophageal acid exposure was defined as total acid exposure time ≥6%, ≥9% in upright, and ≥3% in supine body position. These values are used by most centers and based on a large study by Richter et al. 20
Chapter 5
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