title: Safety and efficacy of oral rehydration therapy until 2 h before surgery: a multicenter randomized controlled trial.
abstract: OBJECTIVE
  In many countries, patients are generally allowed to have clear fluids until 2-3 h before surgery. In Japan, long preoperative fasting is still common practice. To shorten the preoperative fasting period in Japan, we tested the safety and efficacy of oral rehydration therapy until 2 h before surgery.
  
  
  METHODS
  Three hundred low-risk patients scheduled for morning surgery in six university-affiliated hospitals were randomly assigned to an oral rehydration solution (ORS) group or to a fasting group. Patients in the ORS group consumed up to 1,000 ml of ORS containing balanced glucose and electrolytes: 500 ml between 2100 the night before surgery and the time they woke up the next morning and 500 ml during the morning of surgery until 2 h before surgery. Patients in the fasting group started fasting at 2100 the night before surgery. Primary endpoints were gastric fluid volume and pH immediately after anesthesia induction. Several physiological measures of hydration and electrolytes including the fractional excretion of sodium (FENa) and the fractional excretion of urea nitrogen (FEUN) were also evaluated.
  
  
  RESULTS
  Mean (SD) gastric fluid volume immediately after anesthesia induction was 15.1 (14.0) ml in the ORS group and 17.5 (23.2) ml in the fasting group (P = 0.30). The mean difference between the ORS group and fasting group was -2.5 ml. The 95% confidence interval ranged from -7.1 to +2.2 ml and did not include the noninferior limit of +8 ml. Mean (SD) gastric fluid pH was 2.1 (1.9) in the ORS group and 2.2 (2.0) in the fasting group (P = 0.59). In the ORS group, mean FENa and FEUN immediately after anesthesia induction were both significantly greater than those in the fasting group (P < 0.001 for both variables). The ORS group reported they had been less thirsty and hungry before surgery (P < 0.001, 0.01).
  
  
  CONCLUSIONS
  Oral rehydration therapy until 2 h before surgery is safe and feasible in the low-risk Japanese surgical population. Physicians are encouraged to use this practice to maintain the amount of water in the body and electrolytes and to improve the patient's comfort.
authors: Department of Anesthesiology, Tokai University School of Medicine, Tokai University Hospital, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan.
authors: Kenji
authors: K
authors: Itou
authors: Tatsuya
authors: T
authors: Fukuyama
authors: Yusuke
authors: Y
authors: Sasabuchi
authors: Hiroyuki
authors: H
authors: Yasuda
authors: Norihito
authors: N
authors: Suzuki
authors: Hajime
authors: H
authors: Hinenoya
authors: Chol
authors: C
authors: Kim
authors: Masamitsu
authors: M
authors: Sanui
authors: Hideki
authors: H
authors: Taniguchi
authors: Hideki
authors: H
authors: Miyao
authors: Norimasa
authors: N
authors: Seo
authors: Mamoru
authors: M
authors: Takeuchi
authors: Yasuhide
authors: Y
authors: Iwao
authors: Atsuhiro
authors: A
authors: Sakamoto
authors: Yoshihisa
authors: Y
authors: Fujita
authors: Toshiyasu
authors: T
authors: Suzuki
mesh_terms: D000328:Adult; D000368:Aged; D005215:Fasting; D005260:Female; D005440:Fluid Therapy / Q000009:adverse effects*; D005745:Gastric Acidity Determination; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D012964:Sodium / Q000378:metabolism; D013997:Time Factors; D014508:Urea / Q000378:metabolism
chemical_list: D014508:Urea; D012964:Sodium