Improving Muscle Function in Nutritionally at Risk, Elderly Patients

Phase II, Multi-center, Randomized Control Trial of Beta- Hydroxy-Methyl-Butyrate (HMB) in Improving Physical Muscle Function, in Nutritionally at Risk, Elderly Patients

The investigators propose to conduct a randomized, control trial of β-hydroxy-β-methylbutyrate (HMB) supplementation in elderly patients (≥65 years of age) with acute respiratory failure, who are identified at high risk for malnutrition by ICU-specific nutritional risk scores. Patients will receive either 3g of HMB daily, or control, daily until day 28 following randomization (even if discharged).The investigators will measure functional outcomes using standard, validated measures prior and after discharge.

The investigators propose to conduct a randomized, control trial of HMB supplementation in elderly patients (≥65 years of age) with acute respiratory failure, who are identified at high risk for malnutrition by ICU-specific nutritional risk scores. Patients will receive either 3g of HMB daily, or control, daily until day 28 following randomization (even if discharged).the investigators will measure functional outcomes using standard, validated measures prior and after discharge. The investigators hypothesize that this inexpensive nutrient, HMB, along with our supportive measures, reduces muscle loss, improves physical muscle function, and improves quality of life in the longer term following critical illness.

Intervention patients will receive 2 x 237mL bottles of the commercially available liquid HMB protein supplement (3g) (Ensure Active™ Muscle Health) throughout the study. In addition, all patients will be fed according to the Canadian Critical Nutrition Practice Guidelines, and protein/energy requirements will be determined by the local dietitians according to their local practice standards.

Control patients will receive 2 x 237mL bottles of the commercially available nutritional supplement (Ensure® Original) throughout the study. In addition, all patients will be fed according to the Canadian Critical Nutrition Practice Guidelines, and protein/energy requirements will be determined by the local dietitians according to their local practice standards.

HMB 3g/day or iso-nitrogenous control (discussed below) in addition to standard enteral, and parenteral nutritional supplementation and standard nutrition when transferred to the ward. The dose of HMB was chosen based on multiple studies revealing efficacy of 3g/day improving muscle mass and demonstrating an excellent safety profile. Feeding will be initiated as per local practice. Enrolled patients will be randomized to supplementation with HMB (3g) or control will begin within 72 hours of admission to ICU.

Control patients will receive 2 x 237mL bottles of the commercially available nutritional supplement (Ensure® Original) in addition to standard enteral, and parenteral nutritional supplementation and standard nutrition when transferred to the ward throughout the study. While the patient is intubated, the control nutritional supplement will be delivered via the enteral feeding tube. The participant will switch to oral administration once extubated

Inclusion Criteria: Patients age ≥65 years. Acute respiratory failure (ARF, defined by expected mechanical ventilation for > 72 hours from the point of screening) Elevated nutritional risk (NUTRIC score>5 - see below). Exclusion Criteria: Over 72 hours from ICU admission. Not expected to survive another 48 hours Lack of commitment to full, aggressive care Patients who have an absolute contraindication to EN (obstruction, perforation, high output fistula), Pregnant women Prisoners Known allergy to study nutrients Unable to walk prior to current illness.