The oesophageal cardia and regurgitation.

AN understanding of the mechanisms governing the integrity of the cardia is of immense importance to the anaesthetist. The cardia is intimately concerned with the vital problems of vomiting, regurgitation, and aspiration of gastric contents into the lungs, and the lethal potentialities of these complications are only too well known. If any proof be needed, the Report on Deaths Associated with Anaesthesia (Edwards et al., 1956), published under the aegis of the Association of Anaesthetists, reveals the serious menace of regurgitation and aspiration. There cannot be an anaesthetist who has not experienced trouble and anxiety—and often—from these hazards. This being so, it might be interesting to present various views and findings which relate to this problem. Having referred to the importance of cardia, it may seem odd to say that it is doubtfui whether, in point of anatomical fact, it exists at all. In 1719, Claude Helvetius, French philosopher and physician, described a sphincter—the so-called cardiac sphincter—at the gastro-oesophageal junction. Since then, despite the most careful search, nobody has been able to provide any concrete evidence of the existence of this anatomical sphincter, at least not in any demonstrable fashion. It has been curiously controversial —a few anatomists have agreed that there is a morphological sphincter, but the majority have denied it, and in the meantime many ingenious theories have been put forward to account for the undoubted sphincter-like function at the lower end of the oesophagus. The position today is only gradually becoming more clear than when Helvetius first described a cardiac sphincter. There does seem to be an obvious everyday need to