title: Randomised clinical study comparing the effectiveness and physiological effects of hypertonic and isotonic polyethylene glycol solutions for bowel cleansing.
abstract: OBJECTIVE
  Bowel cleansing is necessary before colonoscopy, but is a burden to patients because of the long cleansing time and large dose volume. A low-volume (2 L) hypertonic polyethylene glycol-ascorbic acid solution (PEG-Asc) has been introduced, but its possible dehydration effects have not been quantitatively studied. We compared the efficacy and safety including the dehydration risk between hypertonic PEG-Asc and isotonic PEG regimens.
  
  
  METHODS
  This was an observer-blinded randomised study. Participants (n=310) were allocated to receive 1 of 3 regimens on the day of colonoscopy: PEG-Asc (1.5 L) and water (0.75 L) dosed with 1 split (PEG-Asc-S) or 4 splits (PEG-Asc-M), or PEG-electrolyte solution (PEG-ES; 2.25 L) dosed with no split. Dehydration was analysed by measuring haematocrit (Ht).
  
  
  RESULTS
  The cleansing time using the hypertonic PEG-Asc-S (3.33±0.48 hours) was significantly longer than that with isotonic PEG-ES (3.05±0.56 hours; p<0.001). PEG-Asc-M (3.00±0.53 hours) did not have this same disadvantage. Successful cleansing was achieved in more than 94% of participants using each of the 3 regimens. The percentage changes in Ht from baseline (before dosing) to the end of dosing with PEG-Asc-S (3.53±3.32%) and PEG-Asc-M (4.11±3.07%) were significantly greater than that with PEG-ES (1.31±3.01%).
  
  
  CONCLUSIONS
  These 3 lower volume regimens were efficacious and had no serious adverse effects. Even patients cleansed with isotonic PEG-ES showed significant physiological dehydration at the end of dosing. The four-split PEG-Asc-M regimen is recommended because of its shorter cleansing time without causing serious nausea.
  
  
  BACKGROUND
  UMIN000013103; Results.
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Hiro-O
authors.initials: HO
authors.lastname: Yamano
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Hiro-O
authors.initials: HO
authors.lastname: Matsushita
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Yoshikawa
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Takagi
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Harada
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Nakaoka
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Ryogo
authors.initials: R
authors.lastname: Himori
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yoshida
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Kentarou
authors.initials: K
authors.lastname: Satou
authors.affiliation: Digestive Disease Center, Akita Red Cross Hospital , Akita , Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Imai
keywords: COLONOSCOPY; ENDOSCOPIC PROCEDURES; ENDOSCOPY