Improved Reflux Monitoring in the Acute Gastroesophageal Reflux Porcine Model Using Esophageal Multichannel Intraluminal Impedance Measurement

Background  Acute animal models are needed to obtain further insights into the mechanism of gastroesophageal reflux disease. Existing acute models use imprecise methods to detect reflux. The aim of the present study was to evaluate the potential of esophageal multichannel intraluminal impedance measurement (MII) to improve the quality of results of acute reflux porcine models. Materials and Methods  MII was used in ten pigs to monitor gastroesophageal reflux. Measurements were obtained (A) before and (B) after mobilization of the esophagus and (C) after myotomy. The results were compared to those obtained when reflux was monitored by esophageal drainage of intragastrically infused blue solution (DBS). Results  The times to first appearance of reflux were 67% (A), 86% (B), and 57% (C) of those by DBS when detected by MII; p < 0.05. The respective values for intragastric pressures needed to provoke reflux were 46%, 76%, and 66%; p < 0.05. Although the lower esophageal sphincter pressure decreased by 69% after (B) the intragastric pressure needed to provoke reflux increased by 140%; p < 0.05. Conclusions  MII improves the detection of reflux in the acute reflux porcine model. The finding that after sole mobilization of the esophagus the intragastric pressure needed to provoke reflux was increased although the finding that the pressure of the lower esophageal sphincter was decreased needs further investigation.