title: Warming barium sulfate improves esophageal leak detection in pig model.
abstract: BACKGROUND
  Barium esophagograms have poor sensitivity in detecting leaks. We hypothesized that heating barium would decrease viscosity, facilitate extravasation, and enhance its sensitivity in detecting esophageal leaks.
  
  
  METHODS
  We characterized the viscosity of barium at increasing temperatures. We measured the radiopacity of barium at 25°C and 50°C. We determined the smallest diameter defect in esophagus that barium can detect by perforating a porcine esophageal segment with angiocatheters of various diameters, injecting barium at 25°C, and observing extravasation of contrast. We repeated this with barium heated to 30°C, 40°C, 50°C, and 70°C. To determine the ability of barium to detect a staple line leak, we perforated a stapled esophageal segment by air insufflation, injected barium at different temperatures, and monitored extravasation. We used Visipaque, a water-soluble contrast agent, for comparison in all experiments.
  
  
  RESULTS
  The viscosity of barium decreased with increasing temperature. The radiopacity of barium did not change with increasing temperature and was higher than that of Visipaque (P < 0.001). The size of the smallest detectable leak decreased from 2.1 mm with barium at 25°C to 1.3 mm at 40°C and 1.1 mm with Visipaque (P < 0.0001). The sensitivity of staple line leak detection increased from 0% for barium at 25°C to 80% (P = 0.02) with barium at 40°C. There was no significant difference in sensitivity between barium at 40°C and Visipaque.
  
  
  CONCLUSIONS
  Barium warmed to 40°C offers the best sensitivity of esophageal leak detection without compromising radiopacity. Barium at 40°C may be the optimum choice for swallow study to detect esophageal leaks.
authors.affiliation: Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.
authors.forename: Vignesh
authors.initials: V
authors.lastname: Raman
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.
authors.forename: Caitlyn E
authors.initials: CE
authors.lastname: MacGlaflin
authors.affiliation: Department of Surgery, Geisel School of Medicine at Dartmouth, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, New Hampshire.
authors.forename: Karen L
authors.initials: KL
authors.lastname: Moodie
authors.affiliation: Temple University School of Medicine, Temple University, Philadelphia, Pennsylvania; Temple University Health System, Temple University, Philadelphia, Pennsylvania.
authors.forename: Larry R
authors.initials: LR
authors.lastname: Kaiser
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, Temple University Health System, Philadelphia, Pennsylvania. Electronic address: cherie.p.erkmen@tuhs.temple.edu.
authors.forename: Cherie P
authors.initials: CP
authors.lastname: Erkmen
mesh_terms: D000818:Animals; D001466:Barium Sulfate; D004939:Esophageal Perforation / Q000000981:diagnostic imaging*; D006358:Hot Temperature; D023421:Models, Animal; D011859:Radiography; D011897:Random Allocation; D013552:Swine; D014783:Viscosity
chemical_list: D001466:Barium Sulfate
keywords: Anastomotic leak; Barium swallow; Esophageal cancer; Esophageal perforation; Esophagectomy; Fluoroscopy