Title: Mo1266 THE ENDOSCOPIC DILATION MONITOR 2 (EDM2) CAN PREDICT IMPROVEMENT IN DYSPHAGIA, MUCOSAL DAMAGE AND NEED FOR REPEAT DILATIONS SUBSEQUENT TO ESOPHAGEAL BALLOON DILATION
Abstract: The EDM2 accurately measures real-time pressure/volume and pressure/time curves, and collects information on energy and power during endoscopic balloon dilation. The aim of this study was to determine if EDM2 recordings can predict outcome of esophageal balloon dilation. Patients with dysphagia undergoing esophageal balloon dilation were included. A dysphagia scale was used before the dilation and 1 week after. The degree of mucosal damage was also recorded. The endoscopist, dilating nurse/tech, and stricture characteristics were recorded. Pressure and volume measurements impacted by the size of the balloon (maximum pressure, maximum volume, minimum pressure after maximum pressure was obtained, and the difference between these pressures and the target pressure) were analyzed by the largest balloon used during the dilation. Only the 18mm balloon had sufficient numbers for analysis. Measurements not impacted by balloon size (time of dilation after maximum pressure, the total and percent time at or above the target pressure, the percent drop in static pressure after the maximum pressure, flow during dilation, and energy utilized) were analyzed using the entire cohort collectively. 50 patients had 60 dilations during the study period. The average age was 64 and 62% were male. Dilations were performed by 6 different endoscopists, and 24 different endoscopy nurse/techs. The average inflation time after max pressure was obtained was 45sec. During this time the balloon was at or above target pressure on average 25% of the time. For variables grouped by 18mm balloon size, the greater the maximum pressure, and the greater the difference between the maximum pressure and the target pressure, the less likely a repeat dilation was needed (p-values 0.031, and 0.030, respectively). Dysphagia improvement was predicted by the difference between the maximum and minimum pressures (p=0.017). For variables analyzed collectively, dysphagia improvement was predicted by longer time of inflation past maximum (p=0.027), and a mucosal etiology of the stricture (p=0.013). Mucosal damage was predicted by proximal stricture location (p=0.001), longer stricture length (p=0.001), percent drop in static pressure after the maximum pressure was reached (p=0.023), and greater flow rate of water through the catheter (p=0.009). Need for repeat dilation was predicted by proximal stricture location (p=0.031), and higher maximum energy used for dilation (p=0.027). The assistant inflating the dilation balloon keeps the balloon at target pressure or above only 25% of the time after maximum pressure is reached. Real-time measurements in pressure and flow, as well as calculated utilized energy, can predict degree of mucosal damage and need for repeat dilation in patients undergoing esophageal balloon dilation for an esophageal stricture.