The act of vomiting in man.

The mechanism of vomiting in mammals is highly complex, and some aspects of it are not well understood despite the many experimental studies which have been made, particularly in cats and dogs. For example, there is still room for debate about the gastric and intestinal movements during nausea, about the role of the stomach in vomiting, and about the mechanism of opening of the cardia. The reported studies of the act of vomiting in man are comparatively few. Most of these were fluoro-scopic studies of persons vomiting after a bismuth or barium meal and were made many years ago with x-ray apparatus which would today be regarded as primitive. It was unsuitable for taking radiographs during the act because the long exposure times would have resulted in blurring from movement. We ourselves, while performing routine barium meal examinations with modern x-ray apparatus, have seen patients become nauseated, start retching, and even sometimes actually vomit. We have observed the movements which take place in the duodenum, stomach, and lower oesophagus, and have taken radiographs of these organs before, during , and after vomiting. In the present paper we report three selected cases which illustrate the mechanism of vomiting when the stomach is normal. CASE REPORTS CASE 1 A married woman, aged 54 years, complained of nausea and vomiting of recent onset. Before examination she had taken Telepaque which outlined the biliary tree, and barium examination of the oesophagus and stomach with the patient standing showed normal appearances on fluoroscopy. After the duodenal bulb had filled and a little barium had passed on into the second and third parts of the duodenum, a 12 x 10 in. radiograph was exposed (Fig. 1). The patient was already experiencing nausea at this stage of the examination and she soon began retching. Two further 12 x 10 in. radiographs were taken in quick succession (Figs. 2 and 3). At the time when the last of the series of three films was exposed, the patient had actually started to vomit; the cardia had dilated and barium was already passing up from the stomach into the oesophagus. Interpretation of the radiographs The three radio-graphs constitute a record of the act of vomiting in this patient, and from a detailed analysis of them we have been able to form an opinion of the movements which occurred in the proximal duodenum, the stomach, and the lower oesophagus. The first …