[The significance of disordered gastric emptying]

In the last ten years we have learnt much about the pathophysiology of gastric motility and emptying, the study of which has been stimulated by the development of new classes of drugs. Radionuclide methods to measure gastric emptying are now generally accepted as reliable and non-invasive diagnostic tools. Too rapid gastric emptying, especially of liquids, may occur after partial resection of the stomach or after vagotomy. Early satiety, epigastric fullness, nausea and vomiting are its manifestations. 'Classical' dumping symptoms only occur in a minority of cases. Delayed gastric emptying can be brought about by many causes, many of which are transient. Chronic forms of gastric stasis can be caused by several metabolic disturbances, by a number of diseases that affect gastric smooth muscle and by many types of drugs. Abnormalities of the innervation of the stomach as in diabetics with autonomic neuropathy and after truncal vagotomy can give rise to seriously delayed emptying of solid food. These conditions can cause impairment of interdigestive motility that may lead to the development of bezoars. Delayed gastric emptying can also be found in otherwise healthy persons (idiopathic gastroparesis). In a proportion of the patients with idiopathic gastroparesis abnormalities of the electrical control activity of the stomach are found; tachyarrhythmias and tachygastrias. In the treatment of gastric emptying disorders dopamine receptor antagonists (metoclopramide, domperidone) play an important role. These drugs have been found to be both effective and safe. The recently developed substance cisapride enhances gastric motility and emptying, probably through a direct effect on the myenteric plexus in the gut wall.