CI: Initiation of Enteral Nutrition (2012)

Citation:
Dissanaike S, Pham T, Shalhub S, WArner K, Hennessy L, Moore EE, Maier RV, O'Keefe GE, Cuschieri J. Effect of immediate enteral feeding on trauma patients with an open abdomen: Protection from nosocomial infections. J Am Coll Surg. 2008 Nov; 207 (5): 690-697. PMID 18954781.
PubMed ID: 18954781
 
Study Design:
Retrospective Cohort Study
Class:
B - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

The research purpose was to determine safety and impact of EN initiated within 36 hours of injury and completion of acute resuscitation on patients with open abdomens.

Inclusion Criteria:
  • Aged 16 years or older
  • Blunt trauma wound with open abdomen (required damage-control laparotomy or decompression for abdominal compartment syndrome, without primary fascial closure)
  • Arrival at hospital within six hours of injury
  • Either hypotension (systolic BP, 90mmHg) or elevated base deficit at least 6
  • Blood transfusion within 12 hours of injury
  • Body region exclusive of brain with Abbreviated Injury Scale score of at least 2
  • Survival of at least 48 hours and treated with an open abdomen
  • No transmural intestinal injury
  • Intact cervical spinal cord to exclude those with isolated severe head injuries or spinal cord injuries.
Exclusion Criteria:
  • Aged over 16 years
  • Arrival at hospital more than six hours after injury occurred
  • Survival of less than 48 hours
  • No open abdomen
  • Transmural intestinal injury
  • Isolated severe head injury or spinal cord injury.
Description of Study Protocol:
  • Recruitment: Patients at seven trauma centers participated between April 2004 and March 2007
  • Design: Retrospective cohort study
  • Blinding used: Not applicable
  • Intervention: Exposure to EN within 36 hours.

Statistical Analysis

  • Relationship between EN within 36 hours and injury characteristics
    • X2 analysis for categorical variables
    • T-test for continuous variables.
  • All variables with P<0.1 on uni-variate analysis were entered into a forward step-wise regression model to identify risk factors for delay in abdominal closure and development of pneumomia: Cox proportional hazards regression was used to evaluate the effect of EN on time to development of ventilator-associated pneumonia.
Data Collection Summary:

Dependent Variables

  • Multi-organ dysfunction (MOD score)
  • LOS (ICU and hospital days)
  • Mortality (hospital death)
  • Ventilator-associated pneumonia
  • Abdominal closure (patients closed and day of closure, laparotomies).

Independent Variables

Early enteral feeding.

Control Variables

Step-wise regression for multi-variate analyses.

Description of Actual Data Sample:

Initial N

  • 100 trauma patients with open abdomen
  • 32 (65% male) with EN within 36 hours
  • 68 (73.5% male) with EN later than 36 hours
  • P=0.416.

Attrition (Final N)

Not applicable.

Age

  • Early EN: 40±17 years (N=32)
  • No early EN: 39±18 years (N=68).

Ethnicity

No difference by group (P>0.05)

  • Early EN
    • Caucasian: 93.8%
    • African-American: 3.1%
    • Asian: 3.1%
    • Other: 0%.
  • No early EN
    • Caucasian: 89.7%
    • African-American: 5.9%
    • Asian: 1.5%
    • Other: 2.9%.

Other Relevant Demographics

ISS±SD

  • EN feeds: 34±13
  • Controls: 36±13
  • P=0.786.

Anthropometrics

BMI

  • Early EN: 28±1.0
  • No early EN: 29±0.8
  • P=0.696.

Location

USA.

Summary of Results:

Key Findings

No difference in outcomes except for ventilator-associated

Variables

Early EN
Mean±SD

Control Group
Mean±SD

Statistical Significance of Group Difference

Days on Mechanical Ventilation

17.4±2.7

19.3±3.0

P=0.668

ICU LOS

 20.7±2.7

 22.6±3.0

P=0.689

Hospital LOS

 32.9±4.0

 33.0±3.3

P=0.992

Maximum Multiple Organ Dysfunction Score
7.3±.05
8.0±0.4
P=0.274
Ventilator-Associated Pneumonia (%)
43.8%
72.1%
P=0.008
Mortality
12.5%
23.5%
P=0.285

 Other Findings

 No difference in patients with abdominal closure,day of closure or number of laparotomies.

Author Conclusion:
  • It is safe to provide early EN to patients with severe trauma and there is no effect on abdominal closure rate
  • Reduction of ventilator-associated pneumonia is a benefit of early EN.
Funding Source:
Government: U54 GM062119-1
University/Hospital: Massachusetts General Hospital
Reviewer Comments:

This research was secondary analysis of data from a prior study.

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? Yes
  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) Yes
  3.2. Were distribution of disease status, prognostic factors, and other factors (e.g., demographics) similar across study groups at baseline? Yes
  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? 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? N/A
  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? N/A
  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? 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? Yes
  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? Yes
  6.5. Were co-interventions (e.g., ancillary treatments, other therapies) described? Yes
  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? 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)? N/A
  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? 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