title: Normal saline solution versus other viscous solutions for submucosal injection during endoscopic mucosal resection: a systematic review and meta-analysis.
abstract: OBJECTIVE
  EMR is being increasingly practiced for the removal of large colorectal polyps. A variety of solutions such as normal saline solution (NS) and other viscous and hypertonic solutions (VS) have been used as submucosal injections for EMR. A systematic review and meta-analysis is presented comparing the efficacy and adverse events of EMR performed using NS versus VS.
  
  
  METHODS
  Two independent reviewers conducted a search of all databases for human, randomized controlled trials that compared NS with VS for EMR of colorectal polyps. Data on complete en bloc resection, presence of residual lesions, and adverse events were extracted using a standardized protocol. Pooled odds ratio (OR) estimates along with 95% confidence intervals (CI) were calculated using fixed effect or random effects models.
  
  
  RESULTS
  Five prospective, randomized controlled trials (504 patients) met the inclusion criteria. The mean polyp sizes were 20.84 mm with NS and 21.44 mm with VS. On pooled analysis, a significant increase in en bloc resection (OR, 1.91; 95% CI, 1.11-3.29; P = .02; I2= 0%) and decrease in residual lesions (OR, 0.54; 95% CI, 0.32-0.91; P = .02; I2= 0%) were noted in VS compared with NS. There was no significant difference in the rate of overall adverse events between the 2 groups.
  
  
  CONCLUSIONS
  Use of VS during EMR leads to higher rates of en bloc resection and lower rates of residual lesions compared with NS, without any significant difference in adverse events. Endoscopists could consider using VS for EMR of large colorectal polyps and NS for smaller polyps because there is no significant difference in the outcomes with lesions <2 cm.
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA.
authors.forename: Harathi
authors.initials: H
authors.lastname: Yandrapu
authors.affiliation: Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Madhav
authors.initials: M
authors.lastname: Desai
authors.affiliation: Department of Gastroenterology, University of Missouri-Columbia, Columbia, Missouri, USA.
authors.forename: Sameer
authors.initials: S
authors.lastname: Siddique
authors.affiliation: Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Prashanth
authors.initials: P
authors.lastname: Vennalganti
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA.
authors.forename: Sreekar
authors.initials: S
authors.lastname: Vennalaganti
authors.affiliation: Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Sravanthi
authors.initials: S
authors.lastname: Parasa
authors.affiliation: Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Tarun
authors.initials: T
authors.lastname: Rai
authors.affiliation: Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Vijay
authors.initials: V
authors.lastname: Kanakadandi
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA.
authors.forename: Ajay
authors.initials: A
authors.lastname: Bansal
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Titi
authors.affiliation: Department of Gastroenterology, Instituto Clinico Humanitas, Milan, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Repici
authors.affiliation: Department of Gastroenterology, University of Missouri-Columbia, Columbia, Missouri, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Bechtold
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA; Department of Gastroenterology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
authors.forename: Prateek
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Department of Gastroenterology, Kansas City Veterans Affairs Medical Center, Kansas City, Missouri, USA.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Choudhary
mesh_terms: D003111:Colonic Polyps / Q000601:surgery*; D000069916:Endoscopic Mucosal Resection / Q000379:methods*; D005780:Gelatin / Q000627:therapeutic use*; D005950:Glucose Solution, Hypertonic / Q000627:therapeutic use*; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use*; D006895:Hydroxyethyl Starch Derivatives / Q000627:therapeutic use*; D006982:Hypertonic Solutions / Q000627:therapeutic use; D007267:Injections; D007417:Intestinal Polyps / Q000601:surgery; D016017:Odds Ratio; D012965:Sodium Chloride / Q000627:therapeutic use*; D013386:Succinates / Q000627:therapeutic use*; D055675:Viscosupplements / Q000627:therapeutic use*
chemical_list: D005950:Glucose Solution, Hypertonic; D006895:Hydroxyethyl Starch Derivatives; D006982:Hypertonic Solutions; D013386:Succinates; D055675:Viscosupplements; C060085:succinylated gelatin; D012965:Sodium Chloride; D005780:Gelatin; D006820:Hyaluronic Acid