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Updated: May 11, 2026

Simultaneous Laryngopharyngeal and Conventional Esophageal pH Monitoring
Published on: December 14, 2020
Effect of Propofol on Acid Reflux Measured with the Bravo pH Monitoring System
Anupama Chawla1, Eugenia Girda, Grace Walker
1Division of Pediatric Gastroenterology, Stony Brook Long Island Children's Hospital, Health Science Center T11-080, Stony Brook, NY 11794, USA.
Abstract:
Background/Aim. The aim of this study was to determine the effect of propofol on acid reflux as measured with the Bravo pH monitoring system. Methods. 48-hour pH tracings of 88 children were retrospectively evaluated after placement of the Bravo capsule under propofol. Comparisons between day 1 and day 2, as well as 6-hour corresponding segments from day 1 and day 2, were made. Results. The number of reflux episodes was significantly increased during the first six-hour period on day one as compared to day 2 (P = 0.006). The fraction of time the pH was <4 was also increased during this period, though it did not reach statistical significance. When comparing full 24-hour periods, there was no difference noted in either the number of reflux episodes or the fraction of time pH < 4 between day one and day two. Conclusion. Our data suggest an increase in gastroesophageal reflux during the postanesthesia period. This could be a direct effect of propofol, or related to other factors. Regardless of the cause, monitoring of pH for the first 6 hours following propofol administration may not be reliable when assessing these patients. Monitoring pH over a prolonged 48-hour time period can overcome this obstacle.
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