Pediatric Critical Illness
Conditions
Keywords
Pediatric Critical Illness, weight under 10 kilogram, Indirect calorimetry, Energy expenditure, Nutritional assessment, Q-NRG+, Pediatric intensive care, chofield equation, Metabolic monitoring
Brief summary
Indirect calorimetry is considered the reference method for measuring energy expenditure in intensive care patients. However, in infants and small children weighing less than 10 kilograms, its clinical use has historically been limited due to technical challenges related to low tidal volumes, potential increases in dead space, and measurement precision. The goal of this observational study is to evaluate the feasibility and performance of indirect calorimetry using the Q-NRG+ device in critically ill children weighing less than 10 kg who are admitted to a pediatric intensive care unit.
Detailed description
Indirect calorimetry measures oxygen consumption and carbon dioxide production to calculate resting energy expenditure and is considered the reference method in intensive care. In mechanically ventilated pediatric patients, resting energy expenditure is commonly used as a surrogate for total energy expenditure, as activity-related expenditure is minimal due to sedation and ventilation. Despite its clinical relevance, the use of indirect calorimetry in children weighing less than 10 kg has been limited by technical challenges related to low tidal volumes and measurement precision. The Q-NRG+ is an indirect calorimeter designed to measure resting energy expenditure in mechanically ventilated and spontaneously breathing patients. This prospective, single-center observational study will be conducted in a pediatric intensive care unit. Critically ill children weighing less than 10 kg who require mechanical ventilation or are spontaneously breathing and able to tolerate indirect calorimetry measurement using a canopy hood will be eligible for inclusion. Indirect calorimetry measurements will be performed according to a predefined protocol during the course of critical illness. For the measurement, a sampling module will be connected to the ventilator circuit without increasing ventilator dead space. The system continuously samples inspired and expired gases, and energy expenditure is calculated based on measured oxygen consumption and carbon dioxide production in combination with ventilator parameters. The primary objective is to evaluate the feasibility of indirect calorimetry using the Q-NRG+ in critically ill children weighing less than 10 kg, defined as the proportion of technically valid and clinically interpretable measurements. Secondary objectives are to describe measured resting energy expenditure (kcal/kg/day) in this population, to evaluate changes in measured energy expenditure over the course of critical illness, and to compare measured energy expenditure with predicted energy requirements calculated using standard predictive equations. Demographic and clinical variables relevant to metabolic status (age, weight, diagnosis, ventilator settings, sedation, and phase of illness) will be collected from medical records. Descriptive and comparative statistical analyses will be performed.
Interventions
DEVICEQ-NRG+
The Q-NRG+ is an indirect calorimetry device used to measure resting energy expenditure in mechanically ventilated or spontaneously breathing patients. In this study, the device is connected to the ventilator circuit or used with a canopy hood to measure oxygen consumption and carbon dioxide production for calculation of energy expenditure. Measurements are performed in addition to standard clinical care and do not alter routine treatment.
Sponsors
Karolinska Institutet
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Healthy volunteers
No
Inclusion criteria
Newborns and infants admitted to the PICU with body weight from 0,5 up to 10 kilograms. Either requiring mechanically ventilation, with FiO2 \< 70%, PIP\<30 cmH2O and no leakage in the ventilation system. Or spontaneous breathing patients tolerating measurements with canopy.
Exclusion criteria
In mechanically ventilated patients' unstable ventilation including ventilation settings changed during the last 60 minutes (FiO2 \>70%, PIP\>30 cmH2O, or ventilation system leakage). Patients spontaneous breathing not tolerating measurements with canopy.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Feasibility of Q-NRG+ indirect calorimetry measurements | From first enrollment until end of study (During PICU stay (Q2 2026 - Q4 2027) | Feasibility is defined as the proportion of attempted Q-NRG+ measurements in infants weighing 0.5-10 kg that result in technically valid and clinically interpretable data according to predefined quality criteria (i) variability \<10% over a 15-minute period with constant Vt/MV (tidal volume/minute ventilation) and (ii) respiratory Quotient (RQ) within the range of \</=1 or \>/=0.7. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Agreement between carbon dioxide production measured by Q-NRG+ and volumetric capnography, Capnostat 5 | During PICU stay (Day 1 to Day 7), when simultaneous Q-NRG+ and Capnostat 5 measurements are available (up to 5 measurements per patient). | Comparison of carbon dioxide production measured using the Q-NRG+ device with obtained via other volumetric capnography already used in the clinic when available. |
| Agreement between measured resting energy expenditure and predicted through Schofield equation. | During PICU stay, at each Q-NRG+ measurement (up to 5 measurements per patient). | Comparison between resting energy expenditure measured by Q-NRG+ and estimated using the Schofield equation, commonly used in peadiatric intensive care units. |
| Change in measured resting energy expenditure across phases of critical illness. | Daily during PICU stay, up to 5 Q-NRG+ measurements per patient. | Evaluation of variation in measured REE during acute, stable, and recovery phases of critical illness. |
| Agreement between oxygen consumtion and carbondioxid production derived from blood gas respiratory quotient and Q-NRG+ measurements | Measurements will be collected from the time of first enrollment until the end of the study (Q2 2026 - Q4 2027). | Comparison between oxygen consumtion and carbondioxid production calculated from blood gas central venous and arteriall and measured using Q-NRG+. |
| Development of predictive model for resting energy expenditure in critically ill children under 10 kilograms. | During PICU stay, based on repeated Q-NRG+ measurements (up to 5 measurements per patient). | Exploratory analysis to develop predictive equations for REE based on repeated Q-NRG+ measurements. |
Countries
Sweden
Contacts
CONTACTMirjam Larsson, Ass Senior Consultant PhD stud
CONTACTUrban Fläring, Ass prof, senior consultant
Outcome results
None listed