Proximal versus distal oesophageal motility as assessed by combined impedance and manometry

BackgroundRegional differences in oesophageal motility have been shown in primary peristalsis, but it is unclear whether such differences occur in secondary peristalsis. We investigated whether oesophageal motor function differs between the proximal and distal oesophagus.MethodsEleven healthy subjects were studied with combined impedance and manometry. Saline and solid agar boluses of 5 ml were applied for primary peristalsis, and secondary peristalsis was stimulated by rapid mid-oesophageal injections of saline. Impedance tracings were analysed and compared for bolus presence time, bolus transit time in the proximal and distal oesophagus.ResultsMost of the manometric parameters were not significantly different between the proximal and distal oesophagus. Bolus presence time was longer in the distal oesophagus for both primary peristalsis and secondary peristalsis (p < 0.001). The proximal bolus transit time was shorter than the distal bolus transit time during saline and solid swallows (p < 0.001). Bolus transit time and bolus presence time were shorter for primary peristalsis than secondary peristalsis induced by saline injection.ConclusionOur data demonstrated that the impedance technique can successfully detect functional differences between the proximal and distal oesophagus, and such differences were still noticeable when the oesophagus was directly stimulated by saline injection.