Nutrient Uptake During Continuous Enteral Feeding

NCT ID: NCT05628844

Last Updated: 2022-12-02

Basic Information

• Recruitment Status: NOT_YET_RECRUITING
• Total Enrollment: 20 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2023-01-01
• Study Completion Date: 2026-12-31

Brief Summary

Continuous enteral nutrition is used to feed patients in intensive care who are unable to eat normally. The goal of this observational study is to learn about the uptake of nutrients from feeding formula. The study method will first be applied in healthy persons to establish workability and normal values, then in patients in the intensive care unit to learn how nutrient uptake is affected by critical illness.

The main questions this study aims to answer are:

• what is the time course of uptake of phenylalanine (an amino acid) and glucose (a sugar) from enteral feeding formula given continuously over several hours
• what is the time course of the filling volume of the stomach during continuous enteral feeding

Participants receive feeding formula through a nasogastric feeding tube and blood samples are taken at short intervals to analyse uptake of nutrients into blood. Simultaneously, the filling volume of the stomach is measured by gastric ultrasound.

Detailed Description

Background

The investigators have previously studied the uptake of dietary isotope-labeled phenylalanine and plasma amino acid concentrations in critically ill patients and healthy subjects. During continuous feeding, uptake was unexpectedly found to be highly variable over time. Due to infrequent sampling, the time course of variability could not be modeled mathematically. Also, the underlying physiological mechanisms remain unclear, though it is hypothesized that gastric emptying is a major factor determining temporal variability.

The study here described is a follow-up that includes serial abdominal ultrasound studies to measure gastric emptying, additional indicators/tracers to determine more detail of uptake vs. digestion/transport/metabolism, and makes use of more frequent sampling to allow for detailed mathematical modeling of temporal variability.

Experimental protocol

ICU patients:

• Standard care and treatment as per clinical routines
• Pre-experiment ongoing nutrition for ≥ 6 hrs by nasogastric feeding tube or gastrostomy (not postpyloric)
• Bed rest during experiment as feasible

Healthy subjects

• Keep dietary and training habits for ≥ 2 days before experiment start
• Overnight fast
• Bed rest during experiment as feasible
• Nasogastric feeding tube
• Arterial line in radial or ulnar artery

Nutrition, sampling, measurements

• Experimental nutrition by continuous infusion for 10 hrs
• Infusion rate corresponding to 25 kcal/kg body weight/day (calculated including metabolizable tracers/indicators)
• Arterial blood sampling (à 1 ml) every 5 min in pilot study (may adjust to 10 or 15 min depending on results of pilot study)
• Serial abdominal ultrasound for determination of gastric volume (pilot study will determine how often)

Experimental nutrition

• Commercially available feeding formula for ICU use (Fresubin® HP Energy or similar) with added phenylalanine and glucose indicators
• Intrinsically labeled protein: 13C-L-phenylalanine intrinsically labeled milk protein
• Nonmetabolisable phenylalanine analogue: D-phenylalanine
• Free amino acid tracer: stable isotope-labeled phenylalanine tracer (2H5-L-Phe)
• Non-metabolizable glucose analogue: 3-O-Methyl-d-glucose (3-OMG)
• Free glucose tracer: isotope labeled D-glucose

Analyses

• arterial plasma amino acid and glucose tracers as above
• arterial plasma 3-OMG
• arterial plasma aminograms
• arterial plasma glucose, insulin, c peptide

Conditions

Critical Illness

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Healthy subjects

Healthy persons ≥ 18 yrs of age

Continuous enteral feeding

Intervention Type: PROCEDURE

Enteral nutrition by continuous infusion for 10 hrs at a dose corresponding to 25 kcal/kg body weight/day

Critically ill patients

Critically ill patients ≥ 18 yrs of age admitted to the ICU

Continuous enteral feeding

Intervention Type: PROCEDURE

Enteral nutrition by continuous infusion for 10 hrs at a dose corresponding to 25 kcal/kg body weight/day

Interventions

Continuous enteral feeding

Enteral nutrition by continuous infusion for 10 hrs at a dose corresponding to 25 kcal/kg body weight/day

Intervention Type: PROCEDURE

Other Intervention Names

Gastric ultrasound

Eligibility Criteria

Inclusion Criteria

• stable enteral nutrition of >80% of measured or calculated energy expenditure by nasogastric feeding tube or gastrostomy

• healthy volunteer

Exclusion Criteria

• enteral nutrition by postpyloric route such as jejunostomy or postpyloric tube
• remaining ICU stay expected < 12 hrs
• ongoing bleeding that requires surgery/intervention or transfusion of > 2 units red cells/24 hrs
• inability to use feeding tube or arterial line

• any condition or medication affecting nutrition or metabolism

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Karolinska University Hospital

OTHER

Sponsor Role: collaborator

Karolinska Institutet

OTHER

Sponsor Role: collaborator

Felix Liebau

OTHER_GOV

Sponsor Role: lead

Responsible Party

Felix Liebau

Principal Investigator

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Felix Liebau, MD PhD

Role: PRINCIPAL_INVESTIGATOR

Karolinska University Hospital

Central Contacts

Felix Liebau, MD PhD

Role: CONTACT

felix.liebau@regionstockholm.se

Olav Rooyackers, Prof Phd

Role: CONTACT

olav.rooyackers@ki.se

+46702069227 ext. +46702069227

References

Liebau F, Kiraly E, Olsson D, Wernerman J, Rooyackers O. Uptake of dietary amino acids into arterial blood during continuous enteral feeding in critically ill patients and healthy subjects. Clin Nutr. 2021 Mar;40(3):912-918. doi: 10.1016/j.clnu.2020.06.018. Epub 2020 Jun 30.

Reference Type: BACKGROUND

PMID: 32709553 (View on PubMed)

Other Identifiers

2022-04200-01

Identifier Type: -

Identifier Source: org_study_id