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Randomized Controlled Trial
, 21 (1), 142

A Randomized Trial of Supplemental Parenteral Nutrition in Underweight and Overweight Critically Ill Patients: The TOP-UP Pilot Trial

Randomized Controlled Trial

A Randomized Trial of Supplemental Parenteral Nutrition in Underweight and Overweight Critically Ill Patients: The TOP-UP Pilot Trial

Paul E Wischmeyer et al. Crit Care.


Background: Nutrition guidelines recommendations differ on the use of parenteral nutrition (PN), and existing clinical trial data are inconclusive. Our recent observational data show that amounts of energy/protein received early in the intensive care unit (ICU) affect patient mortality, particularly for inadequate nutrition intake in patients with body mass indices (BMIs) of <25 or >35. Thus, we hypothesized increased nutrition delivery via supplemental PN (SPN) + enteral nutrition (EN) to underweight and obese ICU patients would improve 60-day survival and quality of life (QoL) versus usual care (EN alone).

Methods: In this multicenter, randomized, controlled pilot trial completed in 11 centers across four countries, adult ICU patients with acute respiratory failure expected to require mechanical ventilation for >72 hours and with a BMI of <25 or ≥35 were randomized to receive EN alone or SPN + EN to reach 100% of their prescribed nutrition goal for 7 days after randomization. The primary aim of this pilot trial was to achieve a 30% improvement in nutrition delivery.

Results: In total, 125 patients were enrolled. Over the first 7 post-randomization ICU days, patients in the SPN + EN arm had a 26% increase in delivered calories and protein, whereas patients in the EN-alone arm had a 22% increase (both p < 0.001). Surgical ICU patients received poorer EN nutrition delivery and had a significantly greater increase in calorie and protein delivery when receiving SPN versus medical ICU patients. SPN proved feasible to deliver with our prescribed protocol. In this pilot trial, no significant outcome differences were observed between groups, including no difference in infection risk. Potential, although statistically insignificant, trends of reduced hospital mortality and improved discharge functional outcomes and QoL outcomes in the SPN + EN group versus the EN-alone group were observed.

Conclusions: Provision of SPN + EN significantly increased calorie/protein delivery over the first week of ICU residence versus EN alone. This was achieved with no increased infection risk. Given feasibility and consistent encouraging trends in hospital mortality, QoL, and functional endpoints, a full-scale trial of SPN powered to assess these clinical outcome endpoints in high-nutritional-risk ICU patients is indicated-potentially focusing on the more poorly EN-fed surgical ICU setting.

Trial registration: NCT01206166.

Keywords: Calorie delivery; Critical care; Intensive care; Malnutrition; Parenteral Nutrition; Protein; Quality of life.


Fig. 1
Fig. 1
Patient flow diagram. * Exclusion reasons add up to greater than 426 because some patients have multiple exclusion reasons. †The large imbalance between arms is purely due to chance. This imbalance was possible despite the blocked randomization due to the large number of strata with incomplete blocks. ‡ Two EN and three EN+PN patients had no days evaluable for nutritional adequacy due to not having any days after randomization and before discharge or death without oral feeding
Fig. 2
Fig. 2
ICU calorie adequacy. a EN calorie adequacy. b EN + PN calorie adequacy. ○ - SPN + EN group, X - EN alone group. The number of patients in each group on each day of the study is shown at the bottom of the graphs. EN enteral nutrition, PN parenteral nutrition, SPN supplemental parenteral nutrition
Fig. 3
Fig. 3
Hospital and ICU mortality outcomes by subgroup. a Mortality outcomes by admit NUTRIC score <5 (n = 73) and >5 (n = 52). b Mortality outcomes by BMI <25 (n = 65) and >35 (n = 60). Odds ratio for hospital mortality by subgroup. BMI body mass index, EN enteral nutrition, ICU intensive care unit, PN parenteral nutrition

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