title: Prospective, randomized, controlled comparison of the use of polyethylene glycol electrolyte lavage solution in four-liter versus two-liter volumes and pretreatment with either magnesium citrate or bisacodyl for colonoscopy preparation.
abstract: BACKGROUND
  Laxative pretreatment decreases the volume of polyethylene glycol electrolyte lavage solution (PEG-ELS) required for colonoscopy without compromising preparation quality. We compared the use of 4 L of PEG-ELS with the use of 2 L plus a laxative.
  
  
  METHODS
  One hundred fifty consecutive patients (148 men) undergoing outpatient colonoscopy were randomly selected for one of three preparations (Prep 1: 4 L PEG-ELS; Prep 2: 2 L PEG-ELS plus 296 mL magnesium citrate 1 hour prior; Prep 3: 2 L PEG-ELS plus bisacodyl 20 mg). Endoscopists were blinded as to the type of preparation.
  
  
  RESULTS
  Colonoscopy times were 37, 33, and 29.5 minutes (p = 0.02). Satisfaction scores (0 to 11) during preparation were 2.75, 1.84, and 2.54 (p = 0.05). Preparation times were 519, 397, and 379 minutes (p < 0.001). Preparation satisfaction scores (0 to 10) were 6.2, 7.7, and 7.4 (p < 0.001). Endoscopists' scores of preparation quality (1 to 10) were 7.3, 7.8, and 8.1 (p = 0.03). Volumes of liquid stool aspirated were 181, 103, and 90 mL (p < 0.001). Twenty-four patients receiving Prep 2 and 16 receiving Prep 3 had previous colonoscopy using full volume PEG-ELS; 88% who received Prep 2 and 56% who received Prep 3 preferred the newer preparation (p = 0.006).
  
  
  CONCLUSIONS
  Two liters of PEG-ELS plus laxative improved preparation quality and patient satisfaction and reduced preparation time. Magnesium citrate pretreatment had fewer symptoms and was preferred to bisacodyl. PEG-ELS in 2 L quantities could reduce costs, and consideration should be given to making it available commercially.
authors.affiliation: Division of Digestive Diseases and Nutrition, Dorn Veterans' Affairs Medical Center, University of South Carolina at Columbia, 29203-6808, USA.
authors.forename: V K
authors.initials: VK
authors.lastname: Sharma
authors.forename: S K
authors.initials: SK
authors.lastname: Chockalingham
authors.forename: E A
authors.initials: EA
authors.lastname: Ugheoke
authors.forename: A
authors.initials: A
authors.lastname: Kapur
authors.forename: P H
authors.initials: PH
authors.lastname: Ling
authors.forename: R
authors.initials: R
authors.lastname: Vasudeva
authors.forename: C W
authors.initials: CW
authors.lastname: Howden
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001726:Bisacodyl / Q000008:administration & dosage*; D002400:Cathartics / Q000008:administration & dosage*; D019343:Citric Acid / Q000008:administration & dosage*; D003113:Colonoscopy; D005260:Female; D005751:Gastric Lavage / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage*; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D011446:Prospective Studies
chemical_list: D002400:Cathartics; D009942:Organometallic Compounds; D001726:Bisacodyl; D019343:Citric Acid; D011092:Polyethylene Glycols; C110422:magnesium citrate