title: Anticatabolic effects of avoiding preoperative fasting by intravenous hypocaloric nutrition: a randomized clinical trial.
abstract: OBJECTIVE
  We tested the hypothesis that the avoidance of preoperative fasting by hypocaloric nutrition attenuates protein catabolism after surgery.
  
  
  BACKGROUND
  Prolonged fasting before major abdominal procedures has been demonstrated to accentuate the catabolic response to surgery.
  
  
  METHODS
  Twenty-two patients undergoing colorectal cancer surgery were randomly assigned to receive glucose and amino acids intravenously starting either 20 hours before the operation or with surgical skin incision. Nutrition was administered until the second postoperative day, with glucose providing 50% and amino acids 20% of each patient's measured resting energy expenditure. Whole body leucine and glucose kinetics were assessed by L-[1-(13)C]leucine and [6,6-(2)H(2)]glucose before and after surgery. Fractional synthesis rates of muscle protein, albumin, and fibrinogen were determined using primed continuous infusions of L-[(2)H(5)]phenylalanine postoperatively, whereas the expression of mRNA of proteolytic genes in muscle (Mafbx/atrogin-1, ubiquitin, Murf 1) was determined by quantitative RT-PCR. Circulating concentrations of glucose, lactate, amino acids, insulin, glucagon, and cortisol were also measured. This study has been registered at ClinicalTrials.gov (Identifier: NCT00614133).
  
  
  RESULTS
  Preoperative feeding inhibited endogenous protein breakdown (fasting group: 128 +/- 23 micromol . kg(-1) . h(-1); nutrition group: 96 +/- 22 micromol . kg(-1) . h(-1); P = 0.02) and blunted the increase in amino acid oxidation (fasting group: 27 +/- 5 micromol . kg(-1) . h(-1); nutrition group: 20 +/- 5 micromol . kg(-1) . h(-1); P = 0.03), resulting in positive whole-body protein balance after surgery (fasting group: -10 +/- 4 micromol . kg(-1) . h(-1); nutrition group: 1 +/- 3 micromol . kg(-1) . h(-1); P < 0.001). This anabolic response was associated with decreased muscle proteolytic gene expression and increased hepatic albumin synthesis. Total plasma protein, fibrinogen, and muscle protein synthesis were not affected.
  
  
  CONCLUSIONS
  Hypocaloric nutrition decreases protein catabolism, with a contribution from the ubiquitin pathway in muscle, and stimulates albumin synthesis after colorectal surgery if initiated 1 day before the operation.
authors.affiliation: Department of Anesthesia, McGill University, Royal Victoria Hospital, Montreal, Quebec, Canada. thomas.schricker@mcgill.ca
authors.forename: Thomas
authors.initials: T
authors.lastname: Schricker
authors.forename: Sarkis
authors.initials: S
authors.lastname: Meterissian
authors.forename: Ralph
authors.initials: R
authors.lastname: Lattermann
authors.forename: Olasunkamni A J
authors.initials: OA
authors.lastname: Adegoke
authors.forename: Errol B
authors.initials: EB
authors.lastname: Marliss
authors.forename: Louise
authors.initials: L
authors.lastname: Mazza
authors.forename: Leopold
authors.initials: L
authors.lastname: Eberhart
authors.forename: Franco
authors.initials: F
authors.lastname: Carli
authors.forename: Evan
authors.initials: E
authors.lastname: Nitschman
authors.forename: Linda
authors.initials: L
authors.lastname: Wykes
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage* / Q000097:blood; D001786:Blood Glucose / Q000032:analysis; D015179:Colorectal Neoplasms / Q000601:surgery; D017558:Elective Surgical Procedures; D004734:Energy Metabolism; D005215:Fasting; D005934:Glucagon / Q000097:blood; D005947:Glucose / Q000008:administration & dosage*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007328:Insulin / Q000097:blood; D018482:Muscle, Skeletal / Q000378:metabolism; D009752:Nutritional Status; D011300:Preoperative Care; D011506:Proteins / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D007328:Insulin; D011506:Proteins; D005934:Glucagon; D005947:Glucose; D006854:Hydrocortisone