title: Parenteral nutrition and protein sparing after surgery: do we need glucose?
abstract: Although capable of inducing an anabolic state after surgery, parenteral nutrition, including glucose, leads to hyperglycemia. Even moderate increases in blood glucose are associated with poor surgical outcome. We examined the hypothesis that amino acids, in the absence of glucose supply, spare protein while preventing hyperglycemia. In this prospective study, 14 patients with colonic cancer were randomly assigned to undergo a 6-hour stable isotope infusion study (3 hours of fasting followed by 3-hour infusions of amino acids, Travasol [Baxter, Montreal, Canada] 10% at 0.02 mL.kg(-1).min(-1), with or without glucose at 4 mg.kg(-1).min(-1)) on the second day after colorectal surgery. Protein breakdown, protein oxidation, protein balance, and glucose production were assessed by stable isotope tracer kinetics using l-[1-(13)C]leucine and [6,6-(2)H2]glucose. Circulating concentrations of glucose, cortisol, insulin, and glucagon were determined. The administration of amino acids increased protein balance from -16+/-4 micromol.kg(-1).h(-1) in the fasted state to 16+/-3 micromol.kg(-1).h(-1). Combined infusion of amino acids and glucose increased protein balance from -17+/-7 to 7+/-5 micromol.kg(-1).h(-1). The increase in protein balance during nutrition was comparable in the 2 groups (P=.07). Combined administration of amino acids and glucose decreased endogenous glucose production (P=.001) and stimulated insulin secretion (P=.001) to a greater extent than the administration of amino acids alone. Hyperglycemia (blood glucose, 10.1+/-1.9 micromol/L) occurred only in the presence of glucose infusion. In summary, excluding glucose from a short-term feeding protocol does not diminish the protein-sparing effect of amino acids and avoids hyperglycemia.
authors.affiliation: Department of Anesthesia, McGill University Montreal, Canada H3A 1A1. thomas.schricker@mcgill.ca
authors.forename: Thomas
authors.initials: T
authors.lastname: Schricker
authors.forename: Sarkis
authors.initials: S
authors.lastname: Meterissian
authors.forename: Francesco
authors.initials: F
authors.lastname: Donatelli
authors.forename: George
authors.initials: G
authors.lastname: Carvalho
authors.forename: Louise
authors.initials: L
authors.lastname: Mazza
authors.forename: Leopold
authors.initials: L
authors.lastname: Eberhart
authors.forename: Linda
authors.initials: L
authors.lastname: Wykes
authors.forename: Franco
authors.initials: F
authors.lastname: Carli
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000596:Amino Acids / Q000378:metabolism; D000758:Anesthesia; D002153:Calorimetry, Indirect; D002245:Carbon Dioxide / Q000378:metabolism; D005260:Female; D005947:Glucose / Q000378:metabolism* / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005949:Glucose Oxidase / Q000378:metabolism; D006801:Humans; D007651:Keto Acids / Q000097:blood; D007930:Leucine / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption / Q000187:drug effects; D010288:Parenteral Nutrition; D011184:Postoperative Period; D011506:Proteins / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D007651:Keto Acids; D011506:Proteins; D002245:Carbon Dioxide; C013082:alpha-ketoisocaproic acid; D005949:Glucose Oxidase; D007930:Leucine; D005947:Glucose