Faculty Collaboration Database

Performance and optimal technique for pharyngeal impedance recording: A simulated pharyngeal reflux study. Am J Gastroenterol 2007 Jan;102(1):33-9

Date

02/03/2007

Pubmed ID

17266686

DOI

10.1111/j.1572-0241.2006.00888.x

Scopus ID

2-s2.0-33846044720 (requires institutional sign-in at Scopus site)   11 Citations

Abstract

BACKGROUND AND AIMS: Detection rate, influence of recording site, and subject posture for impedance monitoring of pharyngeal reflux of gastric contents remain unknown. We evaluated the ability of the impedance sensor for detection of various volumes of intrapharyngeal infusate at two sites and in two subject positions.

METHODS: Nineteen healthy subjects were studied using concurrent videoendoscopic, manometric, impedance, and pH recording.

RESULTS: Detection rate of simulated pharyngeal reflux events ranged between 87% and 100% for 1-4 mL. Detection rate for 0.1-1 mL volumes in the upright position was significantly higher (78-85%) when the impedance sensor was located at the proximal margin of the upper esophageal sphincter (UES) compared to 2 cm proximally (38-68%) (P < 0.001). With the sensor at 2 cm above the UES, the average detection rate for all volumes in the upright position was significantly less (P < 0.001) compared to the supine position (48%vs 84%). There was substantial variability in the magnitude of impedance changes induced by different infusates.

CONCLUSIONS: Impedance sensors can detect as small a volume as 0.1 mL and combined with a pH sensor can detect acidic and nonacidic liquid and mist reflux events. Sensor placement at the proximal margin of the UES yields the highest detection rate irrespective of subject posture compared to placement 2 cm proximally. Depending on the volume of refluxate and location of the impedance sensor, a substantial minority of simulated reflux events can be missed.

Author List

Aslam M, Bajaj S, Easterling C, Kawamura O, Rittmann T, Hofmann C, Liu J, Shaker R

Author

Reza Shaker MD Assoc Provost, Sr Assoc Dean, Ctr Dir, Chief, Prof in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Chi-Square Distribution
Electric Impedance
Endoscopy, Gastrointestinal
Esophageal pH Monitoring
Female
Gastroesophageal Reflux
Humans
Hydrogen-Ion Concentration
Male
Manometry
Pharynx
Video Recording