Pressure and X-ray recording of reflux into the thoracic stomach.

Anastomotic leakage, pulmonary aspiration and reflux-esophagitis might be induced or aggravated by the increased duodenogastric reflux observed in the thoracic stomach. In this study, the effect of respiration on the reflux-promoting pressure gradient in the intrathoracally located stomach was assessed. In nine patients pressure recording was done in the duodenum and the abdominal and thoracic part of the stomach. Intrapleural pressure was determined by recording mouth pressure during inspiratory occlusion. In addition, the course of injected contrast was examined fluoroscopically. The mean end-expiratory pressure gradient in the thoracic part of the stomach was 0.8 cm H2O, increasing up to 6.0 cm H2O and 21.3 cm H2O during normal and forced inspiration, respectively. Fluoroscopic examination showed reflux of contrast that coincided with the downward movement of the diaphragm. From this study, we conclude that reflux into the thoracic stomach is promoted by intraluminal pressure fluctuations induced by voluntary breathing. Performing a pyloroplasty or -myotomy after intrathoracic esophagogastrostomy destroys the integrity of the pyloric sphincter as a barrier to reflux, thus promoting duodenogastric reflux.