Cold pain prolongs gastric emptying of liquid but not solid meal: an electrical impedance tomography (EIT) study

Stressful stimuli are reported to affect gastric emptying. However, methods for measuring gastric emptying are, in themselves, stressful. Electrical impedance tomography (EIT) is a method for measuring gastric emptying noninvasively. We used EIT to measure gastric emptying of liquid and solid meals to determine the effect of cold pain stress on gastric emptying. EIT (DAS-01P APT system; University of Sheffield, UK) was carried out in six healthy women (age, 21.6 +/- 0.4 [mean +/- SD] years) who had ingested a liquid (potage, 263 g; 139 kcal) or solid (beef patty, 205 g; 435 kcal) test meal. Cold pain stimuli consisted of repeated immersions of the subject's non-dominant hand into ice water (4 degrees C) for 1 min, with a 15-s recovery period between immersions, for a total of 20 min. For the control stimulus, water at 37 degrees C was used. The cold pain stimulus was applied immediately after the ingestion of a test meal. All studies were carried out randomly in each subject at intervals of more than 1 week. With cold pain, the half emptying time of the liquid meal was significantly greater than that with the control stimulus (47.6 +/- 26.1 min vs 28.1 +/- 10.8 min, P < 0.05). For the solid meal, the half emptying time did not differ between stimuli (101.9 +/- 44.8 min with cold pain vs 92.6 +/- 30.5 min with control stimulus). There were no significant differences in lag time between the liquid and solid meals. Cold pain stress delayed gastric emptying of liquid but not solid meals.