The optimal amount of energy and protein a given patient should receive to reduce morbidity and mortality is unclear and remains controversial. Our recent International multicenter observational study of 2772 ICU patients from 165 ICUs showed a significant inverse linear relationship between the odds of mortality and total daily calories received. Increased amounts of calories were most important for the BMI<20 group followed by the BMI 20-<25 group and BMI >35 group with no benefit of increased calorie intake for patients in the BMI 25-<35 group. Thus, a prospective randomized trial is warranted to confirm our hypothesis that in patients with a BMI of <25 and those with a BMI >35 increasing the provision of more energy and protein can impact clinical outcomes.
This pilot study is a multicenter, randomized trial of 160 critically ill patients (>18 years old) with BMI <25 or >35 from 8 - 9 tertiary care ICU’s in Canada, United States, and Europe. Patients will be randomized to one of 2 interventions: enteral nutrition (EN) alone or enteral nutrition plus parenteral nutrition (supplemental PN group). Patients will be stratified on the basis of admission BMI: <25 or >35, medical or surgical admission diagnosis, and by site.
The primary outcome for the definitive study is 60 day mortality. Secondary outcomes include 28 day mortality, hospital mortality, duration of stay (ICU and hospital), multiple organ dysfunction (SOFA and PODS), duration of mechanical ventilation, development of ICU-acquired infections, functional status at hospital discharge, and 3 and 6 month survival and health-related quality of life.
If the results of this pilot study are positive, then we will proceed to a large scale trial of 2000 patients across approximately 40 ICUs to determine the efficacy of the proposed nutritional strategy.