title: Use of a concentrated enteral nutrition solution to increase calorie delivery to critically ill patients: a randomized, double-blind, clinical trial.
abstract: BACKGROUND
  Critically ill patients typically receive ∼60% of estimated calorie requirements.
  
  
  OBJECTIVE
  We aimed to determine whether the substitution of a 1.5-kcal/mL enteral nutrition solution for a 1.0-kcal/mL solution resulted in greater calorie delivery to critically ill patients and establish the feasibility of conducting a multicenter, double-blind, randomized trial to evaluate the effect of an increased calorie delivery on clinical outcomes.
  
  
  METHODS
  A prospective, randomized, double-blind, parallel-group, multicenter study was conducted in 5 Australian intensive care units. One hundred twelve mechanically ventilated patients expected to receive enteral nutrition for ≥2 d were randomly assigned to receive 1.5 (n = 57) or 1.0 (n = 55) kcal/mL enteral nutrition solution at a rate of 1 mL/kg ideal body weight per hour for 10 d. Protein and fiber contents in the 2 solutions were equivalent.
  
  
  RESULTS
  The 2 groups had similar baseline characteristics (1.5 compared with 1.0 kcal/mL). The mean (±SD) age was 56.4 ± 16.8 compared with 56.5 ± 16.1 y, 74% compared with 75% were men, and the Acute Physiology and Chronic Health Evaluation II score was 23 ± 9.1 compared with 22 ± 8.9. The groups received similar volumes of enteral nutrition solution [1221 mL/d (95% CI: 1120, 1322 mL/d) compared with 1259 mL/d (95% CI: 1143, 1374 mL/d); P = 0.628], which led to a 46% increase in daily calories in the group given the 1.5-kcal/mL solution [1832 kcal/d (95% CI: 1681, 1984 kcal/d) compared with 1259 kcal/d (95% CI: 1143, 1374 kcal/d); P < 0.001]. The 1.5-kcal/mL solution was not associated with larger gastric residual volumes or diarrhea. In this feasibility study, there was a trend to a reduced 90-d mortality in patients given 1.5 kcal/mL [11 patients (20%) compared with 20 patients (37%); P = 0.057].
  
  
  CONCLUSIONS
  The substitution of a 1.0- with a 1.5-kcal/mL enteral nutrition solution administered at the same rate resulted in a 46% greater calorie delivery without adverse effects. The results support the conduct of a large-scale trial to evaluate the effect of increased calorie delivery on clinically important outcomes in the critically ill.
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Peake
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Davies
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Adam M
authors.initials: AM
authors.lastname: Deane
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Kylie
authors.initials: K
authors.lastname: Lange
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: John L
authors.initials: JL
authors.lastname: Moran
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Stephanie N
authors.initials: SN
authors.lastname: O'Connor
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Emma J
authors.initials: EJ
authors.lastname: Ridley
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Patricia J
authors.initials: PJ
authors.lastname: Williams
authors.affiliation: From the Queen Elizabeth Hospital (SLP, JLM, and PJW), the Royal Adelaide Hospital (AMD, SNO, and MJC), the Discipline of Acute Care Medicine, University of Adelaide, Adelaide, Australia; the Department of Epidemiology and Preventive Medicine, Australian and New Zealand Intensive Care Research Centre, Monash University, Victoria, Australia (ARD and EJR); and the Centre for Research Excellence in Translating Nutritional Science into Good Health, National Health and Medical Research Council, University of Adelaide, Adelaide, Australia (KL).
authors.forename: Marianne J
authors.initials: MJ
authors.lastname: Chapman
mesh_terms: D018806:APACHE; D000328:Adult; D000368:Aged; D001315:Australia; D015331:Cohort Studies; D003422:Critical Care; D004311:Double-Blind Method; D002149:Energy Intake; D004750:Enteral Nutrition / Q000009:adverse effects; D005240:Feasibility Studies; D005260:Female; D005526:Food, Formulated / Q000009:adverse effects / Q000032:analysis; D006785:Hospitals, University; D006801:Humans; D056865:Ideal Body Weight; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial; D016019:Survival Analysis