title: Effects of a New Metabolic Conditioning Supplement on Perioperative Metabolic Stress and Clinical Outcomes: A Randomized, Placebo-Controlled Trial.
abstract: BACKGROUND
  Insulin resistance is a measure of metabolic stress in the perioperative period. Before now, no clinical trial has determined the summative effects of glutamine, L-carnitine, and antioxidants as metabolic conditioning supplements in the perioperative period.
  
  
  OBJECTIVE
  The purpose of this study was to determine the effects of a new conditioning supplement on perioperative metabolic stress and clinical outcomes in non-diabetic patients.
  
  
  METHODS
  In this randomized controlled trial, 89 non-diabetic patients scheduled for coronary artery bypass grafting, with ejection fractions above 30%, were selected. Using the balanced block randomization method, the patients were allocated to one of four study arms: 1) SP (supplement/placebo): supplement seven days before and placebo 30 days after the surgery; 2) PS: placebo before and supplement after the surgery; 3) SS: supplement before and after the surgery; and 4) PP: placebo before and after the surgery. The supplement was composed of glutamine, L-carnitine, vitamin C, vitamin E, and selenium, which was manufactured for the first time by this research team. Five blood samples were drawn: seven days preoperatively, at the entrance to the operating room, while leaving the operating room, seven days postoperatively, and 30 days postoperatively. Levels of glucose, insulin, and HbA1c were measured in blood samples. Insulin resistance and sensitivity were calculated using a formula. Surgical complications were assessed 30 days postoperatively. Data analysis was done using one-way ANOVA, the Chi-square test, and a general linear model repeated-measures analysis with Bonferroni adjustment.
  
  
  RESULTS
  Blood glucose levels were increased postoperatively in the four groups (< 0.001), but a significantly higher increase occurred in the PP group compared to the SP (0.027), PS (0.026), and SS (0.004) groups. The superficial wound infection rate was significantly different between the four groups (0.021): 26.08% in PP, 9.09% in SP, 4.54% in PS, and 0% in SS.
  
  
  CONCLUSIONS
  Our new metabolic conditioning supplement, whether given pre- or postoperatively, led to better perioperative glycemic control and decreased postsurgical wound infections in non-diabetic patients.
authors.affiliation: Department of Clinical Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Marzieh
authors.initials: M
authors.lastname: Akbarzadeh
authors.affiliation: Department of Clinical Nutrition, School of Nutrition and Food Sciences, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Mohammad Hassan
authors.initials: MH
authors.lastname: Eftekhari
authors.affiliation: Department of Surgery, School of Medicine, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Masih
authors.initials: M
authors.lastname: Shafa
authors.affiliation: Department of Pharmaceutics, School of Pharmacy, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Alipour
authors.affiliation: Department of Epidemiology, School of Health, Shiraz University of Medical Sciences, Shiraz, IR Iran.
authors.forename: Jafar
authors.initials: J
authors.lastname: Hassanzadeh
keywords: Blood Glucose; Infection; Insulin Resistance; Metabolic Stress; Surgery