Effect of bethanechol on esophageal function using multichannel intraluminal impedance (MII)

Abstract

Background: Toward more understanding esophageal motility disorders it is important to have data about bolus movement together with associated peristalsis. In previous studies we have shown, that impedancometry is a reliable technique for recording intestinal chyme transport (1, 2), as well as for studying the dynamics of esophageal bolus transport (3). Now, we performed synchronous manometry and impedancometry in healthy subjects and patients with achalasia using a single catheter in order to test the applicability of this combination for the study of esophageal motility. Materials and Methods: Studies were performed in 8 healthy volunteers and 8 patients with achalasia. A custom-made combine catheter consisting of II impedance segments (each 2cm long) and 4 semiconductor pressure transducers was used. The pressure transducers were located between the impedance channels 1-2, 4-5, 7-8 and 10-11 (intertransducer distance 6 ern). The catheter was passed through the nose into the esophagus as previously described (3). Studies were performed using liquid (10 ml Osmolite) and semisolid boluses (10 ml Yogurt) at supine and upright position. Data were visually analyzed. Results: (a) In healthy subjects bolus transport and associated primary peristalsis with lower sphincter relaxation could be recorded reliably. The patterns were highly unique independent of bolus viscosity and body position. A detailed analysis of the correlation between peristalsis and bolus transit is possible. The propagation of the bolus is significantly faster than the propagation of the associated peristaltic contraction wave. (b) Patients with achalasia featured unique manometry tracings but quite variable impedance tracings, showing that different phenomena can be recorded by the 2 techniques. The spatial and temporal analysis the manometry and impedance tracings indicates that esophageal aperistalsis with simultaneous pressure elevation in achalasia seems to result from a common cavity phenomen. Summary: Simultaneous manometry and impedancometry to study esophageal motility are feasible. Bolus transport and associated peristalsis can be well studied. Both techniques provide different but complementary data on esophageal motility. The combination of both techniques opens new horizons for studying esophageal motility disorders.