Indexed on: 22 Jun '08Published on: 22 Jun '08Published in: Current GERD Reports
In healthy subjects and patients with gastroesophageal reflux disease (GERD), most gastroesophageal reflux events occur during the postprandial period, suggesting a relationship between the volume and characteristics of the gastric contents and the likelihood of reflux. Different techniques have been developed to characterize the dynamics of gastric emptying, including scintigraphy, octanoic acid breath tests, ultrasound, and more recently MRI. Although a delayed gastric emptying increasing gastroesophageal reflux by increasing the availability of material to reflux or by inducing prolonged gastric distension and more transient lower esophageal sphincter relaxations may seem logical, the pathogenic role of delayed gastric emptying in GERD remains controversial. This is because several studies failed to demonstrate a correlation between abnormalities in gastric emptying and GERD symptoms or severity of esophagitis. Furthermore, treatment of GERD with gastric prokinetic drugs has been disappointing. This review discusses the relationship between gastroesophageal reflux and gastric emptying of the whole stomach, the role of postprandial intragastric distribution and emptying of the proximal stomach, and a new hypothesis concerning the effect of gastric emptying, mixing, and buffering capacity of a meal on the frequency and acidity of refluxate.