Using indirect calorimetry to guide nutrition in critically ill obese patients

GuiDIng Energy Provision Using indiREct CalorimeTry: a Pilot Feasibility Randomised Controlled Trial in Critically Ill Adults With Obesity

Not applicable Interventional Australian and New Zealand Intensive Care Research Centre · NCT06053216

This study tests if using a special method to measure how much energy critically ill obese patients need can help them get the right amount of nutrition while they're on a ventilator.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment60 (estimated)
Ages18 Years and up
SexAll
SponsorAustralian and New Zealand Intensive Care Research Centre Academic / other
Locations5 sites (Blacktown, New South Wales and 4 other locations)
Trial IDNCT06053216 on ClinicalTrials.gov

What this trial studies

The DIRECT trial is a multi-centre, feasibility pilot trial aimed at assessing the use of indirect calorimetry to personalize energy delivery in critically ill patients with obesity. It will recruit 60 mechanically ventilated patients from various ICUs in Australia and New Zealand. By measuring energy expenditure through indirect calorimetry, the study seeks to mitigate the risks of under- and overfeeding, which can adversely affect patient outcomes. The trial will also gather data on nutrition, clinical, and safety outcomes to inform a larger definitive trial in the future.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with a body mass index of 30 kg/m2 or higher, receiving invasive mechanical ventilation in the ICU.

Not a fit: Patients receiving extracorporeal membrane oxygenation support or those with major burns may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could lead to improved nutritional management and outcomes for critically ill patients with obesity.

How similar studies have performed: While indirect calorimetry is an established method, this specific application in critically ill obese patients is novel and has not been extensively tested in prior studies.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Adult (≥ 18 years) patients
* Body mass index ≥30 kg/m2
* Between day 3 and 6 of index ICU admission
* Receiving invasive mechanical ventilation
* Receiving enteral or parenteral nutrition

Exclusion Criteria:

* Receiving extracorporeal membrane oxygenation support
* Major burns (≥20% total body surface area)
* Unable to perform indirect calorimetry within 24 hours of randomisation
* Known pregnancy
* Death is imminent
* Treating clinician believes the study is not in the best interest of the patient

Where this trial is running

Blacktown, New South Wales and 4 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Critical IllnessObesityCritical care nutritionIndirect calorimetry
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.