Gastric accommodation in healthy subjects studied by ultrasound, manometry, and impedancemetry

Abstract

Background: Gastric accommodation to a meal may be important in the pathogenesis of upper gastrointestinal disorders, but has been difficult to investigate in a minimally invasive fashion.

Methods: We studied gastric and lower esophageal physiology during food intake, combining transabdominal ultrasound, multichannel high-resolution impedance-manometry (HRIM) and a symptom questionnaire. A HRIM catheter was distally positioned at incisura angularis and 300 mL saline with 75 g glucose was ingested. Target variables were recorded for 30 min after fluid intake.

Key results: Fifteen healthy subjects' participated (11W/4M, median age 23.8 y) and all accepted the meal with few symptoms. At incisura angularis maximum change in pressure from pre-intake values was -7.4 mmHg after 60 s (P < .0001), rising to pre-intake values within 20 min. The corresponding area increased significantly from pre-intake values of 8.0 cm² to 14.1 cm² shortly after intake (P = .0012), peaked at 5 min and slowly decreased towards 30 min. The corresponding maximum change in stress from pre-intake pressure values was -59.2 mmHg shortly after (P < .0001), reaching pre-intake values within 20 min. Strain rose from 0 shortly before to 0.36 shortly after (P < .0001), peaking at 5 min. At incisura angularis, fullness was positively correlated with area and to strain, while fullness, area, and stress were negatively correlated with pressure.

Conclusions & inferences: The multimodal method enabled assessment of the gastric accommodation reflex, stress and strain in the stomach. It triggered few symptoms in healthy volunteers. We propose it to be a more physiological replacement of the barostat technique.

Keywords: gastric accommodation; gastric motility; gastroesophageal reflux; impedancemetry; manometry; ultrasonography.