RT Journal Article SR Electronic T1 Functional disturbance in hiatal hernia in infants and children JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 422 OP 430 DO 10.1136/thx.22.5.422 VO 22 IS 5 A1 A. R. Chrispin A1 G. W. Friedland YR 1967 UL http://thorax.bmj.com/content/22/5/422.abstract AB Retrograde flow from the stomach into the oesophagus in infants and children is prevented by the mucosal choke and muscle cuff of the normally located oesophageal vestibule (Chrispin, Friedland, and Wright, 1967). When a hiatal hernia is present the cardinal functional abnormality is the retrograde flow of gastric content into the oesophagus. An analysis of the factors permitting such flow in these patients is presented in this paper. The important anatomical features are (1) the location of the oesophageal vestibule in the thorax, (2) the phreno-oesophageal membrane with its attachment to both the diaphragm and the vestibule, and (3) the size of the hiatus in the diaphragm. When the oesophageal vestibule lies entirely in the thorax its whole length lies in a zone of subatmospheric pressure. The sharp falls of intrathoracic pressure associated with crying are related to opening of the vestibule. Reduction in tension in the muscle cuff following a dry swallow may also result in vestibular opening with retrograde flow. Inefficient secondary stripping waves may fail to empty the refluxed gastric content from the oesophagus, permitting peptic oesophagitis to develop. The increased tendency to open and the increased difficulty in closing the oesophageal vestibule, because of tension in the abnormally located phreno-oesophageal membrane, are considered. The paradox of free retrograde flow with a small hernia and small retrograde flow with a large hernia is resolved. Basic radiological criteria for establishing the diagnosis of hiatal hernia in this age group are given. The objectives of surgery and the means by which they may be achieved are discussed.