Prebiotic Fiber to Prevent Pathogen Colonization in the ICU

Study Overview
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Brief Summary
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This is a pilot trial testing enteral feeds that are high versus low in prebiotic fiber in 20 critically ill adults. The long-term goal is to determine the efficacy of fiber for the prevention of pathogen colonization/infection in the ICU.

Detailed Description
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This study will test prebiotic fiber in 20 adults who are receiving broad-spectrum antibiotics in the medical or surgical ICU by open-label randomization of patients to approximately 20 g prebiotic fiber/day including 45% short-chain fructooligosaccharides versus 0 g fiber/day by providing one of two feeds. Per 10 ounces of feed, both the high and low fiber feeds contain identical micronutrients and have 296 kilocalorie (kCal), 19 g protein, 8 g fat, and 39 g carbohydrates. The sole difference is that the fiber-containing feed has 4 g fiber including 45% short-chain fructooligosaccharides per 10 ounces whereas the other feed has 0 g fiber. Randomization will take place at the time the order for enteral feeding is placed. Rather than supplying the feed itself, the investigators will supply a randomized recommendation for a feed type (i.e., high vs low fiber) and the feed will be obtained from the hospital pharmacy in the usual manner. Determination of the feed rate and duration will be decided on the individual patient's needs by the treating ICU team. The primary outcome will be to determine whether high fiber feeds alter the gut microbiome in the face of antibiotics and critical illness, calculated by comparing within-individual microbiome differences from baseline to Day 3 in each intervention group.

Official Title
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Prebiotic Fiber to Prevent Pathogen Colonization in the Intensive Care Unit (ICU)

Conditions
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Sepsis

Intervention / Treatment
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* Dietary Supplement: High Fiber
* Dietary Supplement: Low Fiber


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Medical or surgical ICU patients ≥18 years old at our institution; Receiving broad-spectrum antibiotics at the time of enrollment; Deemed appropriate for the study by the treating ICU team; With capacity to give consent or have an appropriate surrogate; Able to undergo assessment within 4 hours of the order for enteral feeds; Expected to receive enteral feeds for ≥3 days but not yet receiving them. Exclusion Criteria: Inability to receive enteral feeds; Celiac disease or known allergy to fiber; Surgery involving the intestinal lumen within 30 days; Limited treatment goals (i.e., do-not-resuscitate (DNR), do-not-intubate (DNI), or no escalation of care); Lack of capacity to consent and lack of an appropriate legally authorized representative.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High Fiber<br>Per 10 ounces of feed: 4 g oat-soy fiber with 45% short-chain fructooligosaccharides, 296 kCal, 19 g protein, 8 g fat, and 39 g carbohydrates. Feed rate/duration individualized for each patient. | Dietary Supplement: High Fiber<br>* See intervention description.<br>|
| Active Comparator: Low Fiber<br>Per 10 ounces of feed: 0 g fiber, 296 kCal, 19 g protein, 8 g fat, and 39 g carbohydrates. Feed rate/duration individualized for each patient. | Dietary Supplement: Low Fiber<br>* See intervention description.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in microbiome measured by LEfSe | An untargeted hierarchical linear discriminant analysis effect size algorithm (LEfSe) will be used to test for within-individual taxonomic differences comparing baseline to Day 3 in the high fiber group as it is an established method for identifying differences in bacterial taxa between any two groups. For those taxa which are significantly altered on LEfSe, the relative change in the high fiber group versus the relative change in the low fiber group will be computed using a rank-sum test. | Baseline and Day 3 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Prebiotic fiber