Bolus flow and biomechanical properties of the esophageal wall during primary esophageal peristalsis: Effects of bolus viscosity and posture

Abstract

Background Studies show that intraluminal impedance recordings of the esophagus allow one to measure the luminal distension during peristalsis, an important parameter for calculation of the biomechanical properties of esophageal wall. The goal was to determine the effect of subject posture and bolus viscosity on the biomechanical properties of esophageal wall, and the rate of bolus flow along the length of the esophagus during primary peristalsis. Methods High‐resolution manometry impedance recordings were obtained in 14 normal healthy subjects. Swallows of 10 ml saline and viscous bolus were recorded in the supine and Trendelenburg positions. User identified the region of interest, and a custom‐designed software extracted parameters of interest such as bolus flow rate, esophageal wall tension, and esophageal wall distensibility in four equal segments of the esophagus. Key Results Bolus flow rate decreases along the length of the esophagus, being slowest in the distal esophagus. Bolus flow rate is smaller in the Trendelenburg position and with viscous bolus as compared with supine position and saline bolus. Esophageal wall tension is greater in the Trendelenburg position and with viscous bolus as compared with the supine position and saline bolus. The esophageal wall distensibility is larger in the distal as compared with proximal esophagus, which is true for both the saline and viscous bolus. Conclusions & Inferences We report, for the first time, bolus flow rate and biomechanical properties of the esophageal wall during swallow‐induced primary peristalsis. Future studies may investigate biomechanical basis of esophageal motility disorders using the methodology described.

Experimental investigations of the human oesophagus: anisotropic properties of the embalmed muscular layer under large deformation

“… 2002 ; Zifan et al. 2021 ) and include the use of ultrasonic probes (Takeda et al. 2002 , 2003 ; Frøkjaer et al.…”

Why so Many Patients With Dysphagia Have Normal Esophageal Function Testing

“…Trendelenburg position and increase in bolus viscosity increases the amplitude of distension, decreases velocity of bolus movement, and distance traveled by bolus due to pharyngeal pump. 62 Distension-contraction waveforms are more closely aligned with each other throughout the length of esophagus with a viscous bolus.…”

“…The important characteristics of distension waveform during peristalsis are 1) the lumen distends in the shape of an “American Football” at each location, along the entire length of the esophagus, 2) the peak of distension moves sequentially along the esophagus, 3) amplitude of distension increases from the proximal to distal location along the length of esophagus, and 4) peak distension velocity and bolus flow rate decrease from proximal to distal location in the esophagus. 62 With regards to the temporal correlation between distension and contraction waveform, the important features are; the pharyngeal pump propels swallowed bolus into the mid esophagus quickly (without any assistance from esophageal contraction) resulting in a significant time interval between the distension and contraction waves in the proximal, mid, and at times in the distal esophagus. On the other hand, there is a closer temporal correlation between the contraction and distension wave in the distal esophagus.…”

Using high resolution manometry impedance to diagnose upper esophageal sphincter and pharyngeal motor disorders

“…Bolus forces acting from within, hyolaryngeal traction forces acting extrinsically, and the intrinsic compliance of the relevant tissue layers are the main determinants of UES opening. The distensibility of the gastrointestinal lumen and sphincters can be inferred using modalities that simultaneously determine luminal CSA (or its equivalent i.e., Ω impedance or mS admittance) and the corresponding intraluminal distension pressure 22,23 . Thus, a low UES MaxAd (<5 th percentile ~ reduced CSA at the peak distension) and/or high IBP (>95 th percentile indicating elevated luminal pressure at peak distension) were considered congruent with impaired UES distensibility.…”