Gastro-oesophageal acid reflux in patients with symptomatic hiatus hernia and effect of a modified Belsey MK IV repair on acid reflux.

Twelve-hour continuous recording of pH at the distal end of the oesophagus was carried out in 59 patients with sliding hiatus hernia and symptoms suggestive of gastro-oesophageal reflux, and the results were compared with those obtained in normal subjects. Mean duration of pH less than or equal to 2.3, pH less than or equal to 3, pH less than or equal to 4 and pH less than or equal to 5, expressed in percentages of the total time of recording, was longer in patients than in normal subjects. There was no difference in mean number of reflux episodes between patients and normal subjects. The clearest separation between the two groups was obtained by the variable 'duration of pH less than or equal to 5'. Irrespective of the variable used, the results did not seem to be related to the degree of severity of the symptoms. Individual sensitivity of the oesophageal mucosa, the content of bilious components in the refluxed material, and the semi-quantitative character of the investigation may, in part, account for the results. Furthermore, the same investigation was carried out before and three months after a modified Belsey MK IV repair in 39 patients with hiatus hernia and symptoms indicating surgical treatment. The operation was followed by a reduction in the tendency to acid reflux, probably as a result of an increase in the competence of the gastro-oesophageal region.