Impact of Body Positioning on EndoFLIP Measurements: A Comparative Study of Supine and Left Lateral Decubitus Positions

This is a prospective, single-center, crossover study comparing EndoFLIP measurements obtained in two patient positions, supine and left lateral decubitus, in pediatric and young adult patients. The Endoluminal Functional Lumen Imaging Probe (EndoFLIP) is an FDA-approved device for patients aged 5 and older that utilizes high-resolution impedance planimetry and volume-controlled distension to assess esophagogastric junction function. Currently, no standardized positioning protocol exists, and proceduralists perform EndoFLIP based on individual preference, either supine or left lateral decubitus. This variability may introduce measurement inconsistencies, particularly when comparing preoperative and postoperative assessments performed in different positions.