Читать книгу Gas Biology Research in Clinical Practice - Группа авторов - Страница 22

Colonic fermentation influences not only the colonic function, but also the function of the upper digestive tract. Reduced proximal gastric tone after cecal infusion of lactulose and short-chain fatty acids [24] and relaxations of the lower esophageal sphincter [25] suggest that colonic fermentation might impair gastric accommodation to meals and induce gastroesophageal reflux. Several studies have shown that the presence of a large volume of air in the proximal stomach triggers stretch receptors in the gastric cardia and leads to an increase in the rate of transient relaxations of the lower esophageal sphincter. The distribution of gas in the digestive tract is easily detected by plain abdominal radiograph. In clinical practice, plain films of the abdomen are required in several different circumstances. The film of the abdomen with the patient standing erect is obtained to demonstrate fluid levels, a more detailed double-contrast view of the intestinal wall, or free air beneath the diaphragm. The other anteroposterior films with the patient lying on his back may corroborate findings on the erect study mainly to evaluate the distribution of the gas pattern of the abdomen. In the erect position, gas is retained largely in the fundus of the stomach. It has been reported that the volume and distribution of gas within the gut is closely associated with abdominal symptoms [26], whereas it has been unclear whether the gastric bubble on plain films is also linked to any symptom. The prevalence of GERD and dyspeptic symptoms were significantly lower in patients with a dome-type gastric bubble in our study [27]. Even a dome-type gastric bubble in the erect position may be distributed throughout the stomach in the supine position if a volume of gastric bubble is sufficient to fill the entire stomach. Changes in the form of gastric bubble detected on a plain film in the erect position may indicate the functional disorder of upper digestive tracts, such as decreased LES pressure, delayed gastric emptying, or impaired accommodation of the proximal stomach.