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Measuring the Metabolic Cost of Fever

Measuring Energy Expenditure Before and After Fever in Critically Ill Children

Status
Terminated
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT02939781
Acronym
IGUANA
Enrollment
12
Registered
2016-10-20
Start date
2016-11-30
Completion date
2018-11-30
Last updated
2021-06-25

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Child, Critical Illness, Fever

Brief summary

Fever is part of the body's immune response, often triggered by infection. Fever is commonly treated with medicines such as paracetamol, mainly because people feel unwell with fever. However fever does have a role in fighting infection: it enables the rest of the immune system to function more efficiently, and may directly stop bacteria and viruses from multiplying. In most cases however treating fever does not matter because the rest of the immune system can cope well enough to fight the infection (with or without additional treatment, like antibiotics). In critically ill patients however any advantage in the fight against infection may be crucial. In a large observational study of adult patients in the intensive care unit, patients who developed an early fever with temperature between 38.5-39.5 degrees C fared relatively better than patients who were colder. So it is possible that in critical illness fever may be beneficial. However in critical illness the body does have limited energy resources. In order to raise the body temperature energy is required. However the investigators do not know how much energy is required to generate a fever in critically ill children. This study will aim to try and measure the energy required to generate a fever in a critically ill child. The investigators will measure energy expenditure directly in children admitted to the intensive care unit by measuring the levels of oxygen and carbon dioxide they breathe in and out (a method called indirect calorimetry). This will enable the investigators to judge whether the benefits of a fever can be justified by the energy costs in the energy depleted state that is critical illness.

Interventions

DEVICEIndirect calorimetry

Indirect calorimetry measurement at baseline (stable state), at onset of fever and continued till fever dehiscence

Sponsors

Great Ormond Street Hospital for Children NHS Foundation Trust
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
0 Years to 15 Years
Healthy volunteers
No

Inclusion criteria

\- all children on the paediatric intensive care unit at Great Ormond Street Hospital who 1. are likely to or have developed a fever (suspected infection, following trauma, post major surgery) 2. are over 10kg (approx 1 year of age) 3. are invasively ventilated

Exclusion criteria

\- Children who 1. have a brain injury, where active temperature control may be instituted 2. patients post cardiac surgery 3. patient with or at risk of cardiac arrhythmias 4. patients post cardiac arrest 5. patient with refractory status epilepticus 6. children with a greater than 5% leak around the endotracheal tube 7. children with a fraction of inspired oxygen \>0.6

Design outcomes

Primary

MeasureTime frameDescription
Percentage Change in Energy Expenditure Per Degree Celsius During Fever and Defervescence6 hoursChildren at risk of fever will have energy expenditure measured by indirect calorimetry at baseline, when the develop a fever, and continuously until fever dehisces. Change in energy expenditure during fever to be calculated as difference in energy expenditure at the maximum temperature minus the energy expenditure at baseline, divided by the difference in temperature. Change in energy expenditure during defervescence to be calculated as difference in energy expenditure at the maximum temperature and the lowest temperature following the fall in temperature, divided by the difference in temperature. Both will also be expressed as a % of the starting energy expenditure (i.e. from baseline for change during fever, from maximum temperature during defervescence)

Participant flow

Participants by arm

ArmCount
Febrile Critically Ill Children
Children above 10kg admitted to the paediatric intensive care unit at Great Ormond Street Hospital who are mechanically ventilated and have a high likelihood of developing a fever. Energy expenditure will be measured using indirect calorimetry at baseline, and continuously during fever, until fever subsides. Indirect calorimetry: Indirect calorimetry measurement at baseline (stable state), at onset of fever and continued till fever dehiscence
12
Total12

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyProtocol Violation8
Overall StudyWithdrawal by Subject1

Baseline characteristics

CharacteristicFebrile Critically Ill Children
Age, Categorical
<=18 years
12 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
0 Participants
Age, Continuous3.7 years
Height106 centimetres
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
2 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
10 Participants
Region of Enrollment
United Kingdom
12 participants
Sex: Female, Male
Female
4 Participants
Sex: Female, Male
Male
8 Participants
Weight16.9 kilograms

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 11
other
Total, other adverse events
0 / 11
serious
Total, serious adverse events
0 / 11

Outcome results

Primary

Percentage Change in Energy Expenditure Per Degree Celsius During Fever and Defervescence

Children at risk of fever will have energy expenditure measured by indirect calorimetry at baseline, when the develop a fever, and continuously until fever dehisces. Change in energy expenditure during fever to be calculated as difference in energy expenditure at the maximum temperature minus the energy expenditure at baseline, divided by the difference in temperature. Change in energy expenditure during defervescence to be calculated as difference in energy expenditure at the maximum temperature and the lowest temperature following the fall in temperature, divided by the difference in temperature. Both will also be expressed as a % of the starting energy expenditure (i.e. from baseline for change during fever, from maximum temperature during defervescence)

Time frame: 6 hours

Population: Only one patient had a calorimetry measurement at baseline followed by a measurement during fever and two patients had measurements during fever, followed by fall in temperature.

ArmMeasureValue (MEAN)Dispersion
Change in Energy Expenditure During FeverPercentage Change in Energy Expenditure Per Degree Celsius During Fever and Defervescence18.8 percentage changeStandard Deviation 6.8
Change in Energy Expenditure During Fever DefervescencePercentage Change in Energy Expenditure Per Degree Celsius During Fever and Defervescence6.3 percentage changeStandard Deviation 6.2

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026