Comparison of anterior, posterior and total fundoplication using a viscera model

Abstract

To determine the contribution of mechanical factors to the function of different types of fundoplication. An experimental bench-top study using abattoir-sourced pig esophagus and stomach placed on a tray. Preliminary esophageal myotomy ensured free reflux of 'intragastric fluid'. Anterior, posterior, and total fundoplications were performed on each of ten sets of viscera. Lower esophageal sphincter pressure was measured using a conventional esophageal manometry catheter. Intragastric pressure was measured with a single channel intragastric manometry catheter, whilst the stomach was inflated with coloured water. The maximum intragastric pressure or the pressure measured when the fundoplication yielded to gastric distension was recorded. All three types of fundoplication restored adequate competence to the gastroesophageal junction, although high-volume gastric infusions resulted in fundoplication yield in 4/10 anterior and 4/10 posterior fundoplications. Gastric distension resulted in fundal dilatation and consequent compression of the adjacent esophagus. Fundoplication generated a median rise of 11-13.5 mmHg in lower esophageal sphincter pressure, comparable to pressures reported in the postoperative clinical setting. Significantly greater intragastric volumes and pressures were tolerated following total fundoplication. This study suggests that mechanical factors could be major contributors to the ability of a fundoplication to restore gastroesophageal competence. Anterior, posterior and total fundoplications are all effective procedures.