title: Use of multiple channel pH monitoring for evaluation of ultra-distal reflux in patients after fundoplication for treatment of Barrett's esophagus.
abstract: Dysplasia and esophageal adenocarcinoma may arise in patients with Barrett's esophagus after fundoplication esophageal pH monitoring showing no acid in esophagus. This suggests the need to develop methodology to evaluate the occurrence of ultra-distal reflux (1cm above the LES). The objective of the study was to compare acid exposition in three different levels: 5cm above the upper border of the LES, 1cm above the LES and in the intrasphincteric region. Eleven patients with Barrett's esophagus after Nissen fundoplication with no clinical, endoscopic and radiologic evidence of reflux were selected. Four-channel pH monitoring took place: channel A, 5cm above the upper border of the LES; channel B, 1cm above the LES; channel C, intrasphincteric; channel D, intragastric. The results of channels A, B and C were compared. There was significant increase in number of reflux episodes and a higher fraction of time with pH <4.0 in channel B compared to channel A. There was significant decrease in fraction of time with pH <4.0 in channel B compared to channel C. Two cases of esophageal adenocarcinoma were diagnosed in the studied patients. The region 1cm above the upper border of the LES is more exposed to acid than the region 5cm above the upper border of the LES, although this exposure occurred in reduced levels. The region 1cm above the upper border of the LES is less exposed to acid than the intrasphincteric region.
authors.affiliation: Digestive Surgery Divison, Department of Gastroenterology, University of São Paulo School of Medicine, São Paulo, Brazil. fc.seguro@uol.com.br
authors.forename: F C B C
authors.initials: FC
authors.lastname: Seguro
authors.forename: M A
authors.initials: MA
authors.lastname: Santo
authors.forename: S
authors.initials: S
authors.lastname: Szachnowicz
authors.forename: F
authors.initials: F
authors.lastname: Maluf Filho
authors.forename: H S
authors.initials: HS
authors.lastname: Kishi
authors.forename: A M
authors.initials: AM
authors.lastname: Falcão
authors.forename: A
authors.initials: A
authors.lastname: Nasi
authors.forename: R A A
authors.initials: RA
authors.lastname: Sallum
authors.forename: I
authors.initials: I
authors.lastname: Cecconello
mesh_terms: D000328:Adult; D000368:Aged; D001471:Barrett Esophagus / Q000503:physiopathology* / Q000601:surgery; D049630:Esophageal Sphincter, Lower / Q000502:physiology*; D005260:Female; D018662:Fundoplication; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008365:Manometry; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods*; D055815:Young Adult