Background: An unbuffered pocket of highly acidic juice is observed at the gastric cardia after a meal in healthy subjects.
Aims: To compare the postprandial acid pocket in healthy subjects and patients with severe reflux disease and define its position relative to anatomical and manometric landmarks.
Methods: 12 healthy subjects and 16 patients with severe reflux disease were studied. While fasted, a station pull-through was performed using a combined dual pH and manometry catheter. Position was confirmed by radiological visualisation of endoscopically-placed radio-opaque clips. The pull-through study was repeated 15 minutes after a standardized fatty meal. Barium meal examination was performed before and following the meal.
Results: A region of unbuffered acid (pH≤ 2) immediately distal to the proximal gastric folds was more frequent in reflux patients (23/32 studies) than in healthy subjects (11/24) (p<0.05). This unbuffered acid pocket was longer in the reflux patients versus healthy subjects (median length 3cm, range 1cm to 15cm vs. 2 cm, range 1cm to 5cm; p<0.05). The acid pocket extended proximally as far as the proximal gastric folds in the patients but stopped a median of 1.1cm distal in healthy subjects (p=0.005). In healthy subjects the acid pocket occupied the distal portion of the sphincter which opened postprandially, whereas in reflux patients it corresponded to the proximal displacement of the gastric folds ie. hiatus hernia.
Conclusion: This enlarged region of unbuffered postprandial acidic juice observed in the patients just below the gastroesophageal junction may contribute to the aetiology of severe reflux disease.
- acid pocket
- gastroesophageal reflux disease
- hernia, hiatal
- lower esophageal sphincter
- period, postprandial