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Indirect calorimetry: applications in practice
1Clinical Nutrition/Pharmacy, St. Joseph Mercy Hospital, 5301 East Huron River Drive, Ann Arbor, MI 48106, USA. wooleyj@trinity-health.org
Respiratory Care Clinics of North America
|December 8, 2006
Summary
Indirect calorimetry (IC) is the standard for measuring energy expenditure in critically ill patients. Measured resting energy expenditure (REE) provides the most accurate caloric target for nutrition support.
Area of Science:
- Critical care medicine
- Nutritional science
- Metabolic research
Background:
- Indirect calorimetry (IC) is the gold standard for assessing energy expenditure in critically ill patients.
- Accurate energy expenditure assessment is crucial for effective nutrition support.
- Standardized protocols are needed to ensure the reliability of IC measurements.
Observation:
- The measured resting energy expenditure (REE) is a patient-specific and objective caloric reference.
- Resting energy expenditure (REE) should be used as the primary caloric target.
- Respiratory quotient (RQ) is primarily an indicator of test validity, not a basis for caloric adjustments.
Findings:
- Measured REE is the most accurate method for determining energy expenditure in intensive care unit (ICU) patients.
- Nutrition support regimens should use measured REE as the target, without added stress or activity factors.
- Protocols for IC methodology are essential for technical accuracy and clinical utility.
Implications:
- Implementing standardized IC protocols can improve the precision of nutrition therapy in ICUs.
- Accurate energy expenditure targets optimize patient outcomes and resource utilization.
- Continuous patient monitoring and data evaluation are vital for effective nutrition intervention.
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