title: Hydrogen leak test is minimally invasive and highly specific for assessment of the integrity of the luminal closure after natural orifice transluminal endoscopic surgery procedures (with video).
abstract: BACKGROUND
  Leak-resistant closure of transluminal access is a major challenge facing natural orifice transluminal endoscopic surgery (NOTES).
  
  
  OBJECTIVE
  To evaluate a hydrogen (H(2))-based leak test for assessment of transluminal-access closure integrity after NOTES procedures.
  
  
  METHODS
  Nine acute porcine experiments.
  
  
  METHODS
  After gastric-wall puncture and balloon dilation, peritoneoscopy was performed, followed by transmural closure of the gastric opening. The animals were randomly assigned to complete or incomplete closure groups. The H(2) leak test was performed by using 1000 mL of 4% H(2) gas mixture and the Hydrogen Leak Detector H2000+. The animals were then euthanized for a methylene blue (MB) test of gastric closure integrity.
  
  
  METHODS
  Intraperitoneal H(2) concentration after gastric insufflation with H(2).
  
  
  RESULTS
  The H(2) leak test was quick and easy. Intraperitoneal H(2) concentrations in parts per million in both groups were similar at baseline (mean +/- SD, 0.18 +/- 0.29 parts per million [ppm] vs 0.22 +/- 0.35 ppm, P = .97) and after balloon dilation (414.8 +/- 198.5 ppm vs 601.3 +/- 116.1 ppm, P > .99). Postclosure intraperitoneal H(2) concentrations dropped to 0.01 +/- 0.77 ppm in the complete-closure group, similar (P = .81) to matched-pairs preopening levels and significantly lower than in the incomplete-closure group (162.0 +/- 83.0 ppm, P < .02). On necropsy, the MB test was negative in all 5 animals of the complete-closure group and positive in all 4 animals of the incomplete-closure group. A cutoff of 25 ppm in intraperitoneal H(2) concentration after closure gave 100% sensitivity, specificity, and positive and negative predictive values for MB leakage.
  
  
  CONCLUSIONS
  Nonsurvival animal experiments.
  
  
  CONCLUSIONS
  The H(2) leak test is highly accurate for detection of leakage after NOTES procedures and could become a substitute for currently used MB leak tests.
authors.affiliation: Division of Gastroenterology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Xavier
authors.initials: X
authors.lastname: Dray
authors.forename: Susan K
authors.initials: SK
authors.lastname: Redding
authors.forename: Eun J
authors.initials: EJ
authors.lastname: Shin
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Buscaglia
authors.forename: Samuel A
authors.initials: SA
authors.lastname: Giday
authors.forename: Ronald J
authors.initials: RJ
authors.lastname: Wroblewski
authors.forename: Lia
authors.initials: L
authors.lastname: Assumpcao
authors.forename: Devi Mukkai
authors.initials: DM
authors.lastname: Krishnamurty
authors.forename: Priscilla
authors.initials: P
authors.lastname: Magno
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Pipitone
authors.forename: Michael R
authors.initials: MR
authors.lastname: Marohn
authors.forename: Anthony N
authors.initials: AN
authors.lastname: Kalloo
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Kantsevoy
mesh_terms: D000818:Animals; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D006859:Hydrogen / Q000032:analysis*; D013552:Swine; D014741:Video Recording
chemical_list: D006859:Hydrogen