J Neurogastroenterol Motil.  2018 Oct;24(4):570-576. 10.5056/jnm18010.

Improving High-resolution Impedance Manometry Using Novel Viscous and Super-viscous Substrates in the Supine and Upright Positions: A Pilot Study

• Wong U
• Person EB
• Castell DO
• von Rosenvinge E
• Raufman JP
• Xie G

• KMID: 2422847
• DOI: http://doi.org/10.5056/jnm18010

Abstract

BACKGROUND/AIMS
Swallows with viscous or solid boluses in different body positions alter esophageal manometry patterns. Limitations of previous studies include lack of standardized viscous substrates and the need for chewing prior to swallowing solid boluses. We hypothesize that high-resolution impedance manometry (HRiM) using standardized viscous and super-viscous swallows in supine and upright positions improves sensitivity for detecting esophageal motility abnormalities when compared with traditional saline swallows. To establish normative values for these novel substrates, we recruited healthy volunteers and performed HRiM.
METHODS
Standardized viscous and super-viscous substrates were prepared using "Thick-It" food thickener and a rotational viscometer. All swallows were administered in 5-mL increments in both supine and upright positions. HRiM metrics and impedance (bolus transit) were calculated. We used a paired two-tailed t test to compare all metrics by position and substrate.
RESULTS
The 5-g, 7-g, and 10-g substrates measured 5000, 36 200, and 64 700 mPa sec, respectively. In 18 volunteers, we observed that the integrated relaxation pressure was lower when upright than when supine for all substrates (P < 0.01). The 10-g substrate significantly increased integrated relaxation pressure when compared to saline in the supine position (P < 0.01). Substrates and positions also affected distal contractile integral, distal latency, and impedance values.
CONCLUSIONS
We examined HRiM values using novel standardized viscous and super-viscous substrates in healthy subjects for both supine and upright positions. We found that viscosity and position affected HRiM Chicago metrics and have potential to increase the sensitivity of esophageal manometry.

Keyword

Esophageal motility disorders; Manometry; Viscous substrates

MeSH Terms

Deglutition
Electric Impedance*
Esophageal Motility Disorders
Healthy Volunteers
Manometry*
Mastication
Pilot Projects*
Relaxation
Supine Position
Swallows
Viscosity
Volunteers