The Energy Dose Study

The investigators have designed this single-center Randomized Clinical Trial (RCT) to prospectively compare, for the first time, the clinical efficacy of different energy doses in intensive care unit (ICU) patients requiring parenteral nutrition (PN) due to intestinal failure/dysfunction. This study intends to enroll a total of 60 patients (20 per energy dose group) to generate critical preliminary data needed to inform subsequent appropriately powered Phase III multicenter trials.

Protein and/or energy deficits are associated with increased rates of hospital infection, skeletal muscle weakness, impaired wound healing, and prolonged convalescence in ICU patients. To prevent or treat malnutrition, enteral nutrition (EN) and/or parenteral nutrition (PN) are routinely given worldwide to a significant proportion of ICU patients. Optimal caloric requirements in critically ill patients are unknown due to a lack of rigorous randomized clinical trials. The comparative efficacy of energy doses in critically ill patients is unknown and clinical recommendations are conflicting and controversial.

The primary aim of this study is to perform a controlled, double-blind, prospective, randomized, intent-to-treat Phase II clinical trial to test the efficacy of three specific energy doses on 28-day total hospital-acquired infections (primary endpoint), blood stream infections (BSI), and other important clinical outcomes in medical/surgical ICU patients requiring specialized parenteral ± enteral feeding. The investigators would also determine the impact of cumulative and mean daily 28-day energy deficits on clinical outcome endpoints; the practical utility of estimated resting energy expenditure (REE) determined by Harris-Benedict equation versus measured REE across different energy doses. The investigators would also like to determine the impact of administered energy dose and energy deficits on global metabolomic patterns over time and their association with key clinical outcomes.

Participants will be randomized to receive one of three specific energy doses, 0.6, 1.0 and 1.3 times measured REE, given for 28 consecutive days during the ICU and post-ICU course.

Eligibility Criteria:
Inclusion Criteria:

* A signed informed consent is in place on the patient's chart
* The patient is at least 18 but not more than 90 years of age at time of ICU admission
* The patient has a body mass index (BMI) less than 40 kg/m\^2
* The patient has been admitted to either a medical or surgical (non-neurological) ICU and is expected to survive and remain in the ICU for at least 72 hours after entry
* There is central venous access for administration of the study PN
* The patient's primary physician(s) will allow the investigative team to manage the study PN and enteral feedings during the current hospitalization
* The patient is expected to require total or partial central venous PN for 7 or more subsequent days after entry on a clinical basis

Exclusion Criteria:

* The patient is pregnant
* The patient has unresuscitated clinical sepsis, defined as unstable blood pressure despite vasopressor support and mean arterial pressure (MAP) \< 60 mm Hg on at least 3 consecutive readings within a 3-hour period during the 24 hours prior to study entry
* The patient was admitted to the ICU following trauma or burns
* The patient has significant renal dysfunction (defined as serum creatinine \> 2.5 mg/dL or deemed to have significant acute kidney injury by the primary physicians) and is not receiving continuous renal replacement therapy (CRRT) or intermittent hemodialysis
* The patient has previously undergone an organ transplantation
* The patient has a current malignancy or is currently receiving an active regimen of chemotherapy and/or radiotherapy to treat a previously diagnosed malignancy
* The patient has a history of HIV/AIDS
* The patient has received any investigational drug within 60 days prior to study entry
* The patient is unable or unwilling to participate in study procedures such as longitudinal blood draws and administration of study nutrient formulations