EAL

CI: Best Method to Estimate RMR (2010)

Citation:

Stucky CC, Moncure M, Hise M, Gossage CM, Northrop D. How accurate are resting energy expenditure prediction equations in obese trauma and burn patients? J Parenter Enteral Nutr. 2008 Jul-Aug; 32(4): 420-426.

PubMed ID: 18596313

Study Design:

Comparison study.

Class:

C - Click here for explanation of classification scheme.

Quality Rating:

POSITIVE: See Quality Criteria Checklist below.

Research Purpose:

The first goal of the study was to evaluate the accuracy of the Harris-Benedict, Cunningham, and Diabetic prediction equations compared with the REE measured by using indirect calorimetry in populations consisting of obese trauma and burn patients only
The second goal was to determine the need for an accuracy of including a stress factor to correct for the trauma or burn injury.

Inclusion Criteria:

This study included adult obese trauma patients and a population of obese burn patients with BMI of 30kg/m² or more.

Exclusion Criteria:

Therapists initially excluded patients with air leaks in the system and those receiving inspired oxygen greater than FiO₂ of 0.6 (equal to 60%).

Description of Study Protocol:

Recruitment

Subjects were adult obese trauma patients and a population of obese burn patients both with BMI of 30kg/m² or more. Patients were treated in the Trauma and Burn Center of University Kansas Hospital from January 2003 to May 2005.

Design

REE was measured in obese trauma and burn patients. Indirect calorimetry and compared with the Harris Benedict and Cunningham equations and an equation using diabetes type II as a factor.

Statistical Analysis

Paired T-test, 95% or more confidence interval, and the Bland-Altman method was used
The results of this analysis were reported by plotting numerical bias vs mean REE (measured + predicted)/2. The numerical bias is defined as the difference between the measured and predicted REE values. The paired T-test was used to determine significant differences between the measured and predicted REE.

Data Collection Summary:

Timing of Measurements

The REE was measured for each patient by indirect calorimetry using a metabolic cart. Values were obtained between the third and fifth post-injury day and weekly thereafter throughout the duration of the patient's stay in the Intensive Care Unit (ICU). All metabolic cart measurements were used in this analysis for two patients in the trauma population and one patient in the burn population.

Dependent Variables

Calculated difference between measured energy expenditure and the estimation by the equations.

Independent Variables

Harris Benedict Equation:

Men: REE = 13.7(Wt) + 5 (Ht) - 6.76 (Age) + 66.47
Women: REE 9.56 (Wt) + 1.85 (Ht) - 4.67 (Age) + 65.5.

Cunningham Equation:

REE = 370 + 21.6 (FFM).

Diabetic:

Men: 71.761 + 2.337 (Age) + 257.293 + 9.996 (Wt) + 4.132 (Ht) + 145.959 (DM)
Women: 71.761 + 2.337 (Age) + 9.996 (Wt) + 4.132 (Ht) + 145.959 (DM).

Abbreviations:

Age in years
Ht is height in cm
Wt is weight in kg
DM is mellitus type 2: Presence = 1 or absence = 0.

Description of Actual Data Sample:

Initial N

28 patients:

Trauma (N=21)
Burn (N=12).

Age

Trauma (48.57±19.07)
Burn (45.42±17.99).

Anthropometrics

Trauma: BMI (kg/m²) 35.39±3.85
Burn: Height (cm) 33.85±1.53.

Location

University of Kansas Hospital.

Summary of Results:

Measured REE for trauma patients:

2,289 ± 571kcal per day (21.37 ± 5.2kcal per kg)

Equations	Estimated kcal per kg	Bias Compared to Measured REE (%)
Harris-Benedict	18.97±2.05	11.98±21.28
Harris-Benedict x 1.2 injury factor	22.76±2.47	-6.68±17.73
Cunningham	16.23±1.95	31.26±26.05
Cunningham x 1.2 injury factor	19.48±2.35	9.38±21.71
Diabetic	18.45±1.87	15.25±23.32
Diabetic x 1.2 injury factor	22.16±2.25	-3.96±19.43

Author Conclusion:

The author concluded that the measured average REE is significantly less than current guidelines. This finding suggests that a hypocaloric regimen is worth considering for ICU patients. Also, if an injury factor of 1.2 is incorporate in certain equations, patients may be given too many calories.

Funding Source:

University/Hospital:

University of Kansas Hospital

Reviewer Comments:

These investigators did not consider body temperature. However, they did not use the measured REE for validation of Penn State University equation.

Quality Criteria Checklist: Primary Research
Relevance Questions
	1.	Would implementing the studied intervention or procedure (if found successful) result in improved outcomes for the patients/clients/population group? (Not Applicable for some epidemiological studies)	Yes
	2.	Did the authors study an outcome (dependent variable) or topic that the patients/clients/population group would care about?	Yes
	3.	Is the focus of the intervention or procedure (independent variable) or topic of study a common issue of concern to dieteticspractice?	Yes
	4.	Is the intervention or procedure feasible? (NA for some epidemiological studies)	Yes

Validity Questions
1.	Was the research question clearly stated?		Yes
	1.1.	Was (were) the specific intervention(s) or procedure(s) [independent variable(s)] identified?	Yes
	1.2.	Was (were) the outcome(s) [dependent variable(s)] clearly indicated?	Yes
	1.3.	Were the target population and setting specified?	Yes
2.	Was the selection of study subjects/patients free from bias?		Yes
	2.1.	Were inclusion/exclusion criteria specified (e.g., risk, point in disease progression, diagnostic or prognosis criteria), and with sufficient detail and without omitting criteria critical to the study?	Yes
	2.2.	Were criteria applied equally to all study groups?	N/A
	2.3.	Were health, demographics, and other characteristics of subjects described?	Yes
	2.4.	Were the subjects/patients a representative sample of the relevant population?	Yes
3.	Were study groups comparable?		Yes
	3.1.	Was the method of assigning subjects/patients to groups described and unbiased? (Method of randomization identified if RCT)	N/A
	3.2.	Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline?	N/A
	3.3.	Were concurrent controls or comparisons used? (Concurrent preferred over historical control or comparison groups.)	Yes
	3.4.	If cohort study or cross-sectional study, were groups comparable on important confounding factors and/or were preexisting differences accounted for by using appropriate adjustments in statistical analysis?	N/A
	3.5.	If case control study, were potential confounding factors comparable for cases and controls? (If case series or trial with subjects serving as own control, this criterion is not applicable.)	N/A
	3.6.	If diagnostic test, was there an independent blind comparison with an appropriate reference standard (e.g., "gold standard")?	Yes
4.	Was method of handling withdrawals described?		Yes
	4.1.	Were follow-up methods described and the same for all groups?	N/A
	4.2.	Was the number, characteristics of withdrawals (i.e., dropouts, lost to follow up, attrition rate) and/or response rate (cross-sectional studies) described for each group? (Follow up goal for a strong study is 80%.)	N/A
	4.3.	Were all enrolled subjects/patients (in the original sample) accounted for?	Yes
	4.4.	Were reasons for withdrawals similar across groups?	N/A
	4.5.	If diagnostic test, was decision to perform reference test not dependent on results of test under study?	Yes
5.	Was blinding used to prevent introduction of bias?		Yes
	5.1.	In intervention study, were subjects, clinicians/practitioners, and investigators blinded to treatment group, as appropriate?	N/A
	5.2.	Were data collectors blinded for outcomes assessment? (If outcome is measured using an objective test, such as a lab value, this criterion is assumed to be met.)	Yes
	5.3.	In cohort study or cross-sectional study, were measurements of outcomes and risk factors blinded?	N/A
	5.4.	In case control study, was case definition explicit and case ascertainment not influenced by exposure status?	N/A
	5.5.	In diagnostic study, were test results blinded to patient history and other test results?	Yes
6.	Were intervention/therapeutic regimens/exposure factor or procedure and any comparison(s) described in detail? Were interveningfactors described?		Yes
	6.1.	In RCT or other intervention trial, were protocols described for all regimens studied?	N/A
	6.2.	In observational study, were interventions, study settings, and clinicians/provider described?	Yes
	6.3.	Was the intensity and duration of the intervention or exposure factor sufficient to produce a meaningful effect?	Yes
	6.4.	Was the amount of exposure and, if relevant, subject/patient compliance measured?	Yes
	6.5.	Were co-interventions (e.g., ancillary treatments, other therapies) described?	N/A
	6.6.	Were extra or unplanned treatments described?	N/A
	6.7.	Was the information for 6.4, 6.5, and 6.6 assessed the same way for all groups?	Yes
	6.8.	In diagnostic study, were details of test administration and replication sufficient?	Yes
7.	Were outcomes clearly defined and the measurements valid and reliable?		Yes
	7.1.	Were primary and secondary endpoints described and relevant to the question?	Yes
	7.2.	Were nutrition measures appropriate to question and outcomes of concern?	N/A
	7.3.	Was the period of follow-up long enough for important outcome(s) to occur?	N/A
	7.4.	Were the observations and measurements based on standard, valid, and reliable data collection instruments/tests/procedures?	Yes
	7.5.	Was the measurement of effect at an appropriate level of precision?	Yes
	7.6.	Were other factors accounted for (measured) that could affect outcomes?	N/A
	7.7.	Were the measurements conducted consistently across groups?	Yes
8.	Was the statistical analysis appropriate for the study design and type of outcome indicators?		Yes
	8.1.	Were statistical analyses adequately described and the results reported appropriately?	Yes
	8.2.	Were correct statistical tests used and assumptions of test not violated?	Yes
	8.3.	Were statistics reported with levels of significance and/or confidence intervals?	Yes
	8.4.	Was "intent to treat" analysis of outcomes done (and as appropriate, was there an analysis of outcomes for those maximally exposed or a dose-response analysis)?	Yes
	8.5.	Were adequate adjustments made for effects of confounding factors that might have affected the outcomes (e.g., multivariate analyses)?	N/A
	8.6.	Was clinical significance as well as statistical significance reported?	N/A
	8.7.	If negative findings, was a power calculation reported to address type 2 error?	N/A
9.	Are conclusions supported by results with biases and limitations taken into consideration?		Yes
	9.1.	Is there a discussion of findings?	Yes
	9.2.	Are biases and study limitations identified and discussed?	Yes
10.	Is bias due to study's funding or sponsorship unlikely?		Yes
	10.1.	Were sources of funding and investigators' affiliations described?	Yes
	10.2.	Was the study free from apparent conflict of interest?	Yes