An interventional study of 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window and 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window in Critical Illness, Enteral Nutrition and Ventilator Associated Pneumonia, sponsored by Hamad Medical Corporation. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-12-08.
Sponsored by Hamad Medical Corporation · Not applicable, Interventional, and Treatment
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:
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
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.
420 studies on the registry are indexed under Pneumonia, Ventilator-Associated; 85 are open to participants now.
This study's planned enrollment of 150 is above the median of 115 across 276 interventional studies indexed under Pneumonia, Ventilator-Associated.
Browse Pneumonia, Ventilator-Associated studies →Hamad Medical Corporation is the lead sponsor of 139 studies on the registry; 27 are open to participants now.
Compared within Pneumonia, Ventilator-Associated, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Critical Illness. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Participants must meet ALL of the following criteria to be eligible for the study:
Patients receiving EN via:
Exclusion Criteria:
Patients with to enteral feeding or pre-existing gastrointestinal disorders, including:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Feeding 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.
Feeding 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.
Behavioral: 20-Hour Cycled Enteral Nutrition with a 4-Hour Fasting Window
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.
Behavioral: 18-Hour Cycled Enteral Nutrition with a 6-Hour Fasting Window
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.
Also known as: Group Intervention 1
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.
Also known as: Group Intervention 2
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.
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).
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).
Time frame: Assessed daily from Day 3 to Day 7.
Nutritional Adequacy
The percentage of the prescribed daily caloric goal that is actually delivered to the patient.
Time frame: Calculated daily from Day 1 to Day 7
Gastrointestinal Complications
Adverse events related to feeding intolerance.
Time frame: Monitored daily from Day 1 to Day 7
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.
Time frame: Measured every 4 hours, daily from Day 1 to Day 7.
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.
Time frame: Daily, from Day 1 to Day 7 of the intervention.
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.
Time frame: Daily, from Day 1 to Day 7 of the intervention.
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.
Time frame: Measured daily from Day 1 to Day 7. The baseline value is recorded on Day 0.
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.
Time frame: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.
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.
Time frame: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.
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.
Time frame: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.
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.
Time frame: Measured daily from Day 1 to Day 7 of the intervention. The baseline value is recorded on Day 0.
Inflammatory Marker
Level of systemic inflammation by Inflammatory Markers (e.g., CRP)
Time frame: Measured daily from Day 1 to Day 7.The baseline value is recorded on Day 0.
Patient Tolerance
The ability to receive enteral nutrition without significant adverse effects.
Time frame: Measured daily from Day 1 to Day 7
No study locations are listed for this record.
Plan to share: 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.
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Nov 2025. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Pneumonia, Ventilator-Associated →