Energy Expenditure in ICU Patients Using Predictive Formulas and Various Body Weights Versus Indirect Calorimetry

Indirect Calorimetry an Essential Tool in the Intensive Care: Comparison of the Energy Expenditure Calculated With Different Body Weights Used in Several Predictive Equations and Indirect Calorimetry Measurements

Indirect calorimetry is the gold standard to measure energy expenditure. In fact it is not always available and inconstantly feasible. Various equations for predicting energy expenditure based on body weights have been created. This study aims at determining the best suitable predictive strategy unless indirect calorimetry is available.

Study Overview

• Status: Completed
• Conditions: Critical Illness; Body Weights

Detailed Description

Several clinical studies have shown that energy deficit as well as overfeeding lead to an increased risk of complications, especially infections, and increased mortality. The gold standard for determining energy expenditure in intensive care patients is indirect calorimetry. This method is expensive and requires a trained team for its use. In addition the reliability of the measurements depends on the clinical situation and may not be feasible (e.g. inspiratory O2 fraction >60%, end expiratory pressure > 9cmH2O, presence of bronchial gap, etc.). Moreover, there is no longer on the market valid indirect calorimeter for clinical use in mechanically ventilated patients, and the maintenance of the old valid one (Deltatrac II®) becomes increasingly problematic because the lack of spare parts. Intensivists have no more choice and use prediction equations for energy expenditure which are based on imprecise anthropometric data (height, weight). Especially for obese or malnourished patients in the intensive care the body weight represents not a reliable data. Similarly, secondary water inflation due to metabolic stress and resuscitation complicates the determination of the real body weight. The difficulty is to know which weight to use in predictive equations. Due to the paucity in literature on this subject, there is currently no consensus on the reference weight to use in the determination of nutritional needs and medication doses. So each prescriber calculates the energy target by taking a reference weight based on his own convictions. This study is part of a quality process of care and practices harmonization, aiming to identify the reference weight to be used and the best suited predictive equation, to predict energy expenditure for patients who cannot benefit from an indirect calorimetry.

• Study Type: Observational
• Enrollment (Actual): 87

Contacts and Locations

Study Locations

• Switzerland
  • Geneva, Switzerland, 1211
    • Service of Intensive Care, Geneva University Hospital,

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

ICU ventilated patients of a tertiary mixed ICU population

Description

Inclusion Criteria:

• Patients admitted to the Geneva ICU
• Length of stay > 72 hours
• Mechanical ventilation with: FiO2 < 60%; positive end expiratory pressure < 9 cmH2O; no air leaks, absence of pulmonary multi-resistant bacteria
• Without mechanical ventilation: no claustrophobia; no oxygen dependence

Exclusion Criteria:

• All patients without inclusion criteria

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
All patients; All ICU patients mechanically ventilated staying more than 72 hours were included and indirect calorimetry was performed and compared to predictive energy expenditure formulas using different body weights.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Best energy expenditure prediction, compared to indirect calorimetry by Deltatrac II vs. various predictive equations based on different body weights (ideal, anamnestic, actual, and adjusted).	Find the best energy expenditure prediction, by comparing results from an indirect calorimetry measurement using the Deltatrac II (considered the reference method), and various predictive equations based on body weight. The ideal body weights (calculated for a body mass index at 22.5 and 25 kg/m2, calculated with the Brocca and Lorentz equations and calculated with the Metropolitan Life Insurance tables), the anamnestic body weight (recorded from the patient/his family members or the electronical medical file), the actual body weight (using a built- in bed scale), and adjusted body weight (determined by correcting the measured body weight according to the cumulative fluid balance) will be recorded and used to calculate various predictive energy expenditure.	Time frame will be 24 hours; no further follow-up will be done.

Collaborators and Investigators

• Sponsor: University Hospital, Geneva
• Investigators: Principal Investigator: Claudia - Paula Heidegger, MD, University Hospital, Geneva

Publications and helpful links

General Publications

• Graf S, Pichard C, Genton L, Oshima T, Heidegger CP. Energy expenditure in mechanically ventilated patients: The weight of body weight! Clin Nutr. 2017 Feb;36(1):224-228. doi: 10.1016/j.clnu.2015.11.007. Epub 2015 Nov 26.

Study record dates

Study Major Dates

• Study Start: April 1, 2014
• Primary Completion (ACTUAL): November 1, 2014
• Study Completion (ACTUAL): November 1, 2014

Study Registration Dates

• First Submitted: August 25, 2015
• First Submitted That Met QC Criteria: September 16, 2015
• First Posted (ESTIMATE): September 17, 2015

Study Record Updates

• Last Update Posted (ESTIMATE): September 17, 2015
• Last Update Submitted That Met QC Criteria: September 16, 2015
• Last Verified: September 1, 2015

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Pathologic Processes; Disease Attributes; Body Weight; Critical Illness
• Other Study ID Numbers: CE:14-070; 13-18 (OTHER_GRANT: APSI)