title: Beneficial Effects of Early Enteral Nutrition After Major Rectal Surgery: A Possible Role for Conditionally Essential Amino Acids? Results of a Randomized Clinical Trial.
abstract: OBJECTIVE
  To investigate direct postoperative outcome and plasma amino acid concentrations in a study comparing early enteral nutrition versus early parenteral nutrition after major rectal surgery. Previously, it was shown that a low plasma glutamine concentration represents poor prognosis in ICU patients.
  
  
  METHODS
  A preplanned substudy of a previous prospective, randomized, open-label, single-centre study, comparing early enteral nutrition versus early parenteral nutrition in patients at high risk of postoperative ileus after surgery for locally advanced or locally recurrent rectal cancer. Early enteral nutrition reduced postoperative ileus, anastomotic leakage, and hospital stay.
  
  
  METHODS
  Tertiary referral centre for locally advanced and recurrent rectal cancer.
  
  
  METHODS
  A total of 123 patients with locally advanced or recurrent rectal carcinoma requiring major rectal surgery.
  
  
  METHODS
  Patients were randomized (ALEA web-based external randomization) preoperatively into two groups: early enteral nutrition (early enteral nutrition, intervention) by nasojejunal tube (n = 61) or early parenteral nutrition (early parenteral nutrition, control) by jugular vein catheter (n = 62). Eight hours after the surgical procedure artificial nutrition was started in hemodynamically stable patients, stimulating oral intake in both groups. Blood samples were collected to measure plasma glutamine, citrulline, and arginine concentrations using a validated ultra performance liquid chromatography-tandem mass spectrometric method.
  
  
  RESULTS
  Baseline concentrations were comparable for both groups. Directly after rectal surgery, a decrease in plasma amino acids was observed. Plasma glutamine concentrations were higher in the parenteral group than in the enteral group on postoperative day 1 (p = 0.027) and day 5 (p = 0.008). Arginine concentrations were also significantly increased in the parenteral group at day 1 (p < 0.001) and day 5 (p = 0.001).
  
  
  CONCLUSIONS
  Lower plasma glutamine and arginine concentrations were measured in the enteral group, whereas a better clinical outcome was observed. We conclude that plasma amino acids do not provide a causal explanation for the observed beneficial effects of early enteral feeding after major rectal surgery.
authors.affiliation: 1Department of Surgery, Research Institute for Nutrition, Toxicology and Metabolism, Maastricht University Medical Centre, Maastricht, The Netherlands. 2Department of Surgery, Catharina Hospital Eindhoven, Eindhoven, The Netherlands. 3Department of Surgery, St. Elisabeth Hospital Tilburg, Tilburg, The Netherlands. 4Department of Clinical Chemistry, Leiden University Medical Centre, Leiden, The Netherlands. 5Department of Clinical Genetics, Maastricht University Medical Centre, Maastricht, The Netherlands. 6Department of Intensive Care Medicine, Catharina Hospital Eindhoven, Eindhoven, The Netherlands. 7Department of Surgery, Research Institute for Growth and Development, Maastricht University Medical Centre, Maastricht, The Netherlands. 8Department of Surgery, Leiden University Medical Centre, Leiden, Maastricht, The Netherlands.
authors.forename: Kevin W Y
authors.initials: KW
authors.lastname: van Barneveld
authors.forename: Boudewijn J J
authors.initials: BJ
authors.lastname: Smeets
authors.forename: Fanny F B M
authors.initials: FF
authors.lastname: Heesakkers
authors.forename: Joanna W A M
authors.initials: JW
authors.lastname: Bosmans
authors.forename: Misha D
authors.initials: MD
authors.lastname: Luyer
authors.forename: Dareczka
authors.initials: D
authors.lastname: Wasowicz
authors.forename: Jaap A
authors.initials: JA
authors.lastname: Bakker
authors.forename: Arnout N
authors.initials: AN
authors.lastname: Roos
authors.forename: Harm J T
authors.initials: HJ
authors.lastname: Rutten
authors.forename: Nicole D
authors.initials: ND
authors.lastname: Bouvy
authors.forename: Petra G
authors.initials: PG
authors.lastname: Boelens
mesh_terms: D000368:Aged; D000596:Amino Acids / Q000097:blood*; D057868:Anastomotic Leak / Q000209:etiology; D001120:Arginine / Q000097:blood; D002956:Citrulline / Q000097:blood; D004750:Enteral Nutrition; D005260:Female; D005973:Glutamine / Q000097:blood; D006801:Humans; D045823:Ileus / Q000209:etiology; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D010288:Parenteral Nutrition; D011182:Postoperative Care / Q000379:methods*; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000596:Amino Acids; D005973:Glutamine; D002956:Citrulline; D001120:Arginine