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Critical IllnessNCT07270939

Optimizing Enteral Nutrition Regimen for Critically Ill Patients

A study testing 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window and 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window in people with Critical Illness and Enteral Nutrition, run by Hamad Medical Corporation.

Not yet recruiting

Opening soon. The study is approved but enrolment has not started yet. Sites may already take enquiries.

Official record
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Trial summary

Clinical Trial The goal of this clinical trial is to learn whether different enteral feeding cycles (18-hour, 20-hour, or standard 24-hour continuous feeding) improve outcomes for critically ill ICU patients who need tube feeding. It will also look at tolerance, nutrition delivery, and safety. Read more about this study

Who is it for?
Ages 18 years and older
What is being tested?
20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window and 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window
Could I receive a placebo?
No, everyone receives an active treatment
How many people
150 participants
Where
No sites listed yet
Study dates
30 Dec 2025to 30 Nov 2026
Phase
Interventional
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Participants must meet ALL of the following criteria to be eligible for the study:
  • Patients aged ≥ 18 years.
  • Patients expected to require enteral nutrition (EN) for ≥ 7 days.
  • Critically ill, mechanically ventilated patients in the ICU.
  • New patients initiating EN in the critical care unit.
  • Patients receiving EN via:
  • a nasogastric (NG) tube.
  • orogastric (OG) feeding tube.

Who cannot join

  • Patients with contraindications to enteral feeding or pre-existing gastrointestinal disorders, including:
  • Active GI bleeding.
  • Progressive GI disease.
  • Recent GI tract resection.
  • Indication for a special diet formula.
  • Need for a large volume of feeding (as determined by the clinical team).
Show all 10Show fewer
  • Pre-existing hepatic failure.
  • Use of a nasojejunal tube, gastrostomy, or jejunostomy.
  • Pregnancy confirmed via β-hCG testing for women of childbearing potential.
  • Insulin-dependent diabetes mellitus.

About this study

Official title: Optimizing Enteral Nutrition: A Comparative Study of 18-Hour, 20-Hour, and 24-Hour

Clinical Trial The goal of this clinical trial is to learn whether different enteral feeding cycles (18-hour, 20-hour, or standard 24-hour continuous feeding) improve outcomes for critically ill ICU patients who need tube feeding. It will also look at tolerance, nutrition delivery, and safety.

The main questions it aims to answer are:

Read more

Do shorter feeding cycles (with fasting windows) reduce ICU length of stay?

Do they lower the risk of infections like ventilator-associated pneumonia?

How do they affect calorie delivery, blood sugar control, and gastrointestinal tolerance?

Researchers will compare:

Continuous 24-hour feeding (standard care)

20-hour feeding with a 4-hour fasting window

18-hour feeding with a 6-hour fasting window

Participants will:

Be critically ill adults in the ICU who require at least 7 days of enteral feeding

Be randomized to one of the three feeding schedules

Receive daily monitoring of calories, protein, blood sugar, and GI tolerance

Have outcomes measured, including ICU length of stay, infections, metabolic control, and feeding tolerance

Read the detailed description

This randomized controlled trial will compare three enteral feeding regimens in critically ill ICU patients: standard 24-hour continuous feeding, 20-hour cycled feeding with a 4-hour fasting window, and 18-hour cycled feeding with a 6-hour fasting window. The rationale is that continuous feeding may impair metabolic regulation, increase insulin requirements, and contribute to gastrointestinal intolerance, while cycled feeding could better align with circadian rhythms, support metabolic balance, and reduce complications such as ventilator-associated pneumonia.

Approximately 150 adult patients who require enteral nutrition for at least seven days will be enrolled across Hamad Medical Corporation ICUs. Participants will be randomized in a 1:1:1 ratio using block randomization through REDCap to ensure allocation concealment. All groups will receive isocaloric enteral nutrition through nasogastric or orogastric tubes, with caloric and protein targets guided by indirect calorimetry or weight-based calculations.

Feeding plans will be initiated within 24 hours of ICU admission or stabilization. Patients assigned to the 18-hour and 20-hour arms will have structured fasting periods, while the control group will receive uninterrupted feeding. Daily assessments will capture nutritional delivery, gastrointestinal tolerance, and metabolic parameters, along with safety monitoring for adverse events. Data will be collected electronically via REDCap, de-identified, and audited regularly by the Clinical Trial Unit.

The study is designed to generate high-quality evidence on whether incorporating fasting windows into feeding schedules can optimize nutrition therapy, improve tolerance, reduce ICU stays, and minimize complications. Findings are expected to inform future ICU nutrition guidelines and contribute to the global discussion on intermittent versus continuous feeding practices.

Being tested
20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window, 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window
Keywords
Cyclic feeding, Feeding window, Critical care nutrition, Gastrointestinal tolerance, Nutritional adequacy
Medical subject headings
Critical Illness, Pneumonia, Ventilator-Associated, Hyperglycemia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting WindowBehavioural

    Also called Group Intervention 1

    20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window (Intervention 1) Objective: To evaluate the physiological benefits of a structured daily fasting period while maintaining a conservative approach to caloric delivery.

  • 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting WindowBehavioural

    Also called Group Intervention 2

    Feeding Schedule involves enteral nutrition over an 18-hour period while incorporating a 6-hour fasting window in each 24-hour cycle. This structure is designed to test a more intense intermittent fasting regimen, aiming to enhance physiological benefits by better aligning with circadian rhythms. The expectations include improved metabolic control, enhanced gastrointestinal motility, and reduced infection rates, with careful monitoring for reduced caloric intake risk. Consequently, the feeding rate is increased to meet daily caloric goals within the 18-hour timeframe, resulting in the most intensive feeding schedule among the three examined arms.

Study groups in NCT07270939
Study groupRoleWhat they receive
24-hour continuous feeding (control)No interventionFeeding Schedule provides continuous enteral nutrition over 24 hours with no fasting window. This standard care in many ICUs serves as the baseline for comparison with two experimental cycled feeding regimens. The feeding rate is designed to evenly deliver the total daily caloric goal across the entire period.
20-hour cycled feeding (intervention)Active comparatorFeeding Schedule consists of enteral nutrition delivered over 20 hours, with a structured 4-hour fasting window each day. This approach aims to balance metabolic and gastrointestinal benefits while ensuring adequate daily caloric intake. Consequently, the feeding rate is increased to meet the total caloric goal within the shorter feeding period.
Receives: Behavioral: 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window
18-hour cycled feeding (intervention)Active comparatorFeeding Schedule involves enteral nutrition over an 18-hour period while incorporating a 6-hour fasting window in each 24-hour cycle. This structure is designed to test a more intense intermittent fasting regimen, aiming to enhance physiological benefits by better aligning with circadian rhythms. The expectations include improved metabolic control, enhanced gastrointestinal motility, and reduced infection rates, with careful monitoring for reduced caloric intake risk. Consequently, the feeding rate is increased to meet daily caloric goals within the 18-hour timeframe, resulting in the most intensive feeding schedule among the three examined arms.
Receives: Behavioral: 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. ICU Length of Stay (LOS)

    The total number of days a patient spends in the intensive care unit, calculated from the date of ICU admission to the date of discharge or transfer out of the ICU.

    Measured: From the date of randomization until the date of ICU discharge or transfer, assessed up to 90 days (or until hospital discharge if it occurs earlier).

Secondary outcomes (11)
  1. Nosocomial Infection/Pneumonia Incidence

    Infections acquired after 48 hours of hospital admission, specifically including Ventilator-Associated Pneumonia (VAP). Diagnosed based on CDC criteria (clinical signs, laboratory findings, and imaging).

    Measured: Assessed daily from Day 3 to Day 7.

  2. Nutritional Adequacy

    The percentage of the prescribed daily caloric goal that is actually delivered to the patient.

    Measured: Calculated daily from Day 1 to Day 7

  3. Gastrointestinal Complications

    Adverse events related to feeding intolerance.

    Measured: Monitored daily from Day 1 to Day 7

  4. Gastric Emptying Index

    A measure of gastrointestinal motility, indicated by delayed gastric emptying. Aspirate gastric contents via a nasogastric (NG) or orogastric (OG) tube at regular intervals (every 4 hours). gastric residual volume ≤ 500 mL, persistently high GRV (>500 mL) indicates delayed emptying.

    Measured: Measured every 4 hours, daily from Day 1 to Day 7.

  5. Glycemic Control

    The regulation of blood glucose levels during the enteral nutrition intervention period.Average daily blood glucose level (mmol/L or mg/dL), calculated from point-of-care testing performed throughout the day.

    Measured: Daily, from Day 1 to Day 7 of the intervention.

  6. Insulin Requirement

    The total daily exogenous insulin dose required to maintain blood glucose within target range.Total insulin dose administered per 24-hour period, measured in units.

    Measured: Daily, from Day 1 to Day 7 of the intervention.

  7. Serum Creatinine level, measured in mg/dL (or µmol/L)

    The change in serum creatinine concentration from baseline serves as a specific biomarker of glomerular filtration rate (GFR) and kidney function.

    Measured: Measured daily from Day 1 to Day 7. The baseline value is recorded on Day 0.

  8. Blood Urea Nitrogen (BUN) level, measured in mg/dL (or mmol/L)

    Change in blood urea nitrogen concentration from baseline, as a biomarker of nitrogenous waste accumulation influenced by renal function, protein catabolism, and hydration status.

    Measured: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.

  9. Alanine Aminotransferase (ALT) level, measured in U/L

    The change in serum alanine aminotransferase (ALT) concentration from baseline serves as a specific biomarker of hepatocellular injury.

    Measured: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.

  10. Aspartate Aminotransferase (AST) level, measured in U/L

    Change in serum aspartate aminotransferase (AST) concentration from baseline, as a biomarker of hepatic inflammation and injury.

    Measured: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.

  11. Total Bilirubin level, measured in mg/dL (or µmol/L)

    The change in serum total bilirubin concentration from baseline serves as a biomarker of hepatic excretory function and bile flow.

    Measured: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted8 Dec 2025
  2. Study start30 Dec 2025 (estimated)
  3. Primary completion30 Nov 2026 (estimated)
  4. Study completion30 Nov 2026 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Model description
Interventional Study Model: Parallel Assignment. Participants are randomized in a 1:1:1 ratio to one of three parallel groups (24-hour continuous feeding, 20-hour cycled feeding, 18-hour cycled feeding) and remain in their assigned group for the study duration.
Masking
None (open label)
Enrolment
150 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT07270939
Sponsor's protocol ID
MRC-01-25-949
Status last verified
Nov 2025
First submitted
23 Sep 2025
Last updated
8 Dec 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No: Data will be collected and de-identified, codes will be used to cover patient identifiers such as Name, HC no., DOB. Any link between code and identifier will be deleted at the end of the data collection and anonymized data will be kept for at least 5 years after study completion. Study participation is documented using a unique study ID (e.g., "EN-001") rather than patient names. Access to identifiers is restricted to the research team and audited by the clinical trial unit (CTU) in HMC. The data that will be collected for this study will remain confidential.

Questions about this trial

What is this clinical trial studying?

A study testing 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window and 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window in people with Critical Illness and Enteral Nutrition, run by Hamad Medical Corporation.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 8 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: opening soon, as of the sponsor's last update on 8 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

ICU Length of Stay (LOS) (time frame: From the date of randomization until the date of ICU discharge or transfer, assessed up to 90 days (or until hospital discharge if it occurs earlier).). It is what the study was designed to measure, not a finding.

Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 Dec 2025.

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