Esophageal Bolus Domain Pressure and Peristalsis Associated With Experimental Induction of Esophagogastric Junction Outflow Obstruction

Background/Aims Intrabolus pressures are important for esophageal bolus transport and may detect obstructed bolus flow. This study measured the effect esophageal outflow obstruction experimentally induce by a leg-lift protocol. Methods Twenty-five gastroesophageal reflux disease patients referred for esophageal manometry and a normal motility diagnosis were included. Supine liquid swallows were tested. Leg-lift protocol generated esophageal outflow obstruction by increasing abdominal pressure. Esophageal pressure topography and intrabolus pressure metrics were calculated. These included, (1) mid-domain bolus distension pressure during esophageal emptying (DPE, mmHg) and (2) ramp pressure (mmHg/sec), generated by compression of the bolus between the peristaltic contraction and esophagogastric junction (EGJ). Results EGJ relaxation pressure was increased by leg-lift from 13 (11-17) to 19 (14-30) mmHg (P < 0.005) and distal contractile integral also increased from 1077 (883-1349) to 1620 (1268-2072) mmHg.cm.sec (P < 0.001) as a physiological response to obstruction. All bolus pressures were increased by leg lift; DPE increased from 17 (15-20) to 27 (19-32) mmHg (P < 0.001), and ramp pressure increased from 3 (1-4) to 5 (2-9) mmHg/sec (P < 0.05). Conclusion Measuring pressures within the intrabolus domain can quantify changes related to obstruction to outflow and may serve as adjunct measures for confirming a diagnosis EGJ outflow obstruction. (J Neurogastroenterol Motil 2022;28:62-68)

Automated summary

This study measured the effect of esophageal outflow obstruction induced by a leg-lift protocol on intrabolus pressures. The results showed an increase in relaxation pressure and distal contractile integral at the esophagogastric junction, as well as increased pressures in all bolus categories. Measuring pressures within the intrabolus domain can aid in confirming a diagnosis of EGJ outflow obstruction.