OP-6 INTRAGASTRIC PRESSURE MEASUREMENT DURING NUTRIENT INTAKE: A NOVEL MINIMALLY INVASIVE METHOD TO MEASURE GASTRIC ACCOMMODATION IN FUNCTIONAL DYSPEPSIA.

Functional dyspepsia (FD) in pediatrics is defined as the presence of upper abdominal symptoms for at least 2 months in the absence of organic or metabolic disease likely to explain the symptoms. The main proposed pathophysiological mechanisms are visceral hypersensitivity,impaired gastric accommodation (GA) and delayed gastric emptying. At present, the gastric barostat is the gold standard to measure GA. However, this procedure is perceived as very invasive and it might alter the normal gastric physiology. Recently, we proposed the intragastric pressure (IGP) measurement during nutrient intake as a potential alternative for assessing GA in adults. This technique uses a thin manometry catheter that measures the IGP over the entire length of the stomach. By means of this study we aim to introduce the HRM as new minimally invasive technique to measure GA and nutrient tolerance in children.After the manometry probe and a second infusion catheter were positioned through the nose into the stomach, the IGP was measured 30 minutes before and during intragastric infusion of nutrient drink (300 Kcal, 60 ml per minute). The patients were asked to score hunger and satiation and 6 epigastric symptoms (fullness, nausea, belching of air, cramps in the abdomen, bloating and pain) at 5-minute intervals. The experiment ended when the volunteers scored maximal satiation at 1-minute intervals by using a graphic rating scale that combines verbal descriptors on a scale graded from 0-5 (1, threshold; 5, maximum satiety).For this study 13 FD pediatric patients (92% female, 14.8 ± 0.8 years old, BMI: 19.5 ± 0.8) and 12 young adult volunteers (100% female, 22.2 ± 0.4 years old, BMI: 21.2 ± 0.3) were recruited. The Rome III questionnaire showed that FD patients suffered mainly from postprandial fullness (75%), epigastric pain (58%), bloating (50%), nausea (50%) and early satiation (42%). In both groups, intragastric infusion of nutrient drink induced a rapid drop in proximal stomach IGP. The average AUC change from baseline was -44.7 ± 11.0 mmHg in patients and -48.4 ± 25.2 mmHg in healthy subjects. Patients tended to score maximal satiation at lower volumes compared healthy subjects (433.8 ± 64.2 ml and 600.0 ± 67.6 mL respectively, p = 0.1). All FD patients and healthy subjects tolerated the catheters and could finalize the study.The IGP measurement during intragastric nutrient drink infusion is a promising minimally invasive alternative to the gastric barostat method to assess GA and nutrient tolerance. Future studies need to increase the patient numbers and compare the measurements in different subsets of pediatric FD (e.g. weight loss vs. no weight loss, present or absent early satiation, etc.).