PROSPECTIVE, RANDOMIZED, CONTROLLED COMPARISON OF THE USE OF POLYETHYLENE-GLYCOL ELECTROLYTE LAVAGE SOLUTION IN 4-LITER VERSUS 2-LITER VOLUMES AND PRETREATMENT WITH EITHER MAGNESIUM CITRATE OR BISACODYL FOR COLONOSCOPY PREPARATION

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 f ifty 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; P rep 3: 2 L PEG-ELS plus bisacodyl 20 mg). Endoscopists were blinded as to the type of preparation. Results: Colonoscopy times were 37, 33, a nd 29.5 minutes (p = 0.02). Satisfaction scores (0 to 11) during prepa ration were 2.75, 1.84, and 2.54 (p = 0.05). Preparation times were 51 9, 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 p reparation quality (1 to 10) were 7.3, 7.8, and 8.1 (p = 0.03). Volume s of liquid stool aspirated were 181, 103, and 90 mL (p < 0.001). Twen ty-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). Con clusions: Two liters of PEG-ELS plus laxative improved preparation qua lity 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 shou ld be given to making it available commercially.