CI: Calorie/Energy Needs (2007)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
The purpose was to discuss the multiple methods used to access nutritional status in chronically ill patients, describe the nutritional status of chronically ill patients, and access the relationship between nutritional indicators and outcomes of mechanical ventilation.
Inclusion Criteria:
  • critically ill patients in a mixed ICU
  • 18 years or older
  • on mechanical ventilation for more than 72 hours
  • hospitalized 7 days or more
Exclusion Criteria:
  • not mechanically ventilated prior to admission
  • neuromuscular condition that precluded weaning from mechanical ventilation
Description of Study Protocol:

Recruitment: A convenience sample of 360 critically ill subjects were consecutively enrolled over 14 months.  Patients were admitted to a mixed  (cardiac, medical, surgical, neurological) ICU.

Design: case series, natural history

Compared nutrition intake with MD orders , RD recommendations and measured energy expenditure every 7 days starting at day 1 of enrollment. Measured indicators of nutritional status at baseline and every 7th day thereafter until the patient died or was discharged from the hospital.

Blinding used: not applicable

Statistical Analysis -Multivariate analyses were conducted using SPSS software, version 11.5. The significance level was set apriori at .05

 

Data Collection Summary:

Timing of Measurements: At admission to study (72 afters after initiation of mechanical ventilation) and every 7 days until discharge measured BMI, serum albumin, prealbumin, magnesium, hemoglobin, phosphorus. If physician order to withhold food and fluids or patient was able to take feeds orally, the patient was excluded for the data analysis for that weekly data collection point.

Dependent Variables
  • Nutrition related health indicators (lab values)
  • Nutritional intake measured as 24 hour energy intake measured both as physicans' feeding orders and as patients' intake
  • Nutritional adequacy (categorized as adequate, under- or over-feeding; based on 
    • patients' intake compared with dietitians' recommendations,
    • physicians' orders compared with dietitian's recommendations
    • patients' intake compared with values determined by using indirect calorimetry
    • energy expenditure measured  by indirect calorimetry while patients receiving mechanical ventilation.

       

Independent Variables - MD orders, RD recommendations (used 25 - 35 kcal/kg/day)

 

 

Description of Actual Data Sample:

Initial N: 360 (202 females, 158 males)

Attrition (final N): not applicable

Age: mean 62.3 (range 18-96)

Ethnicity: not described

Illness Severity:  mean APACHE III Score 75.5

Location: University Hospitals of Cleveland, Cleveland, Ohio

 

Summary of Results:

 Comparison of Patients Energy Intake


% of MD Orders % of RD Recommendations % Energy Expenditure
(Measured by IDC)
Energy Intake  83 ± 27
68 ±  33
105 ±  96

MDs ordered 84 ± 31% of RD recommendations.

Other Findings

  • For time required for weaning, significant relationships with mean levels of albumin during hospitalization and levels of prealbumin at the time of discharge.
  • No statistically significant difference in duration of mechanical ventilation among the 3 nutritional designations (underfeeding, appropriate feeding and overfeeding).
Author Conclusion:
  • These findings are not generalizable to community-based ICUs
  • More studies are needed to determine if patients with extremely low or extremely high body weights have different nutritional requirements than do patients with normal body weights are needed.
  • Further studies are needed to determine the best methods to define nutritional adequacy and to evaluate the nutritional status of patients.
  • Need for well-designed clinical trials related to management of all aspects of nutritional supplementation
Funding Source:
Government: NIH
Reviewer Comments:
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) N/A
 
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? N/A
  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? No
  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.) N/A
  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? Yes
  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")? N/A
4. Was method of handling withdrawals described? No
  4.1. Were follow-up methods described and the same for all groups? No
  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%.) No
  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? N/A
5. Was blinding used to prevent introduction of bias? N/A
  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.) N/A
  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? N/A
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? N/A
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  6.6. Were extra or unplanned treatments described? Yes
  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? N/A
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? Yes
  7.3. Was the period of follow-up long enough for important outcome(s) to occur? Yes
  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? Yes
  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)? Yes
  8.6. Was clinical significance as well as statistical significance reported? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? No
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