CI: Gastric vs. Small Bowel Feeding (2011)


Kearns PJ, Chin D, Mueller L, Wallace K, Jensen WA, Kirsch CM. The incidence of ventilator-associated pneumonia and success in nutrient delivery with gastric vs. small intestinal feeding: A randomized clinical trial. Crit Med. 2000; 28: 1,742-1,746.

PubMed ID: 10890612
Study Design:
Randomized Controlled Trial
A - Click here for explanation of classification scheme.
Quality Rating:
Positive POSITIVE: See Quality Criteria Checklist below.
Research Purpose:

To investigate incidence of VAP and adequacy of nutrient delivery with NG and SB tube feedings.

Inclusion Criteria:
  • All MICU patients who required enteral nutrition for at least three days
  • Able to tolerate either NG or SB feedings.
Exclusion Criteria:
  • Hypotension
  • Abdominal surgery
  • Pancreatitis
  • GI bleeding
  • Ileus.
Description of Study Protocol:


Patients admitted to a 24-bed ICU at a county hospital during a 15-month period.


Randomized controlled trial.


Sealed envelope.


Nurses unaware of location of tube tip.


EN delivered via NG or SB feeding tube.

Statistical Analysis

  • Continuous variables analyzed by Mann-Whitney U-test or unpaired student’s T-test
  • Categorical variables analyzed by Chi square test with a continuity correction and Fisher’s exact test
  • All tests two-tailed with significance set at α=0.05
  • Power analysis was based on published reports of aspiration and predicted that 20 subjects per group allowed 80% power to demonstrate 20% difference in incidence of VAP at α=0.05.
Data Collection Summary:

Timing and Method of Measurements

Patients evaluated 24 hours after intubated for mechanical ventilation. 

Dependent Variables (Outcomes)

  • Primary outcomes: Ratio of mean calories to percent of estimated needs and incidence of VAP
  • Secondary outcomes:
    • Survival
    • Duration of tube feeding
    • ICU and hospital LOS
    • Number of feeding tubes placed
    • Number of blood cultures
    • Days with diarrhea.
Independent Variables (Intervention or Procedure)

Gastric or SB feeding tube placement.

Control Variables
  • REE determined by indirect calorimetry
  • Feedings initiated and maintained per a standard protocol.
Description of Actual Data Sample:
  • Initial N: 44; randomized as 23 in NG group (67% male) and 21 in SB group (70% male)
  • Final N (percent attrition): 42 (one in each group)
  • Age: 49±4 years in NG group and 54±3 years in SB group (P=0.38)
  • Anthropometrics: 
    • APACHE II score: 20±1 NG group and 22±2 in SB group (P=0.38)
    • Weight: 71±3kg and 67±3kg (P=0.40)
  • Location: San Jose, CA.
Summary of Results:

Key Findings

No difference in VAP between EN administered via NG or SB feeding tubes; however, patients receiving SB feedings receive higher amounts of energy and protein.

Outcomes for NG vs. SB Feeding

Outcome NG group SB group Statistical Significance
Percentage REE delivered 47±7 69±7 P<0.05
Mortality 6% 5% P=0.86
ICU LOS (days) 8±1 9±1 P=0.71
Hospital LOS (days) 43±11 39±10 P=0.78
Positive blood cultures (%) 5/16 (31%) 3/11 (27%) P=0.82
Days with diarrhea 2±1 3±1 P=0.13

Other Findings

Number of feeding tubes placed was similar.

Author Conclusion:

There is no clear difference in the incidence of ventilator-associated pneumonia in NG vs. SB feedings. EN delivered in SB do achieve higher caloric and protein intakes.

Funding Source:
Government: California Institute for Medical Research
Ross Laboratories
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) 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? 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")? N/A
4. Was method of handling withdrawals described? Yes
  4.1. Were follow-up methods described and the same for all groups? Yes
  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%.) Yes
  4.3. Were all enrolled subjects/patients (in the original sample) accounted for? Yes
  4.4. Were reasons for withdrawals similar across groups? Yes
  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? Yes
  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? 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? Yes
  6.2. In observational study, were interventions, study settings, and clinicians/provider described? N/A
  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? 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? N/A
  7.7. Were the measurements conducted consistently across groups? N/A
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)? No
  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? Yes
  8.7. If negative findings, was a power calculation reported to address type 2 error? Yes
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