CI: Immune-Modulating Enteral Nutrition (2006)

Citation:

Heys SD, Walker LG, Smith I, Eremin O. Enteral nutritional supplementation with key nutrients in patients with critical illness and cancer; a meta-analysis randomized controlled clinical trials. Annals Surgery, vol 229 (4), 1999 pp467-477.

Worksheet created prior to Spring 2004 using earlier ADA research analysis template.
 
Study Design:
Class:
M - Click here for explanation of classification scheme.
Quality Rating:
Neutral NEUTRAL: See Quality Criteria Checklist below.
Research Purpose:

To conduct a meta-analysis of 11 randomized controlled trials comparing enteral nutritional support supplemented with key nutrients versus standard enteral nutritional support to determine effects on morbidity and mortality rats and hospital stay.

Inclusion Criteria:
  • Randomized
  • Controlled trials
  • Published in peer reviewed journals
  • Patients must be critically ill
  • Trials evaluated use of enteral nutritional support vs. standard enteral nutrition
Exclusion Criteria:
  • Outcome criteria focused on immunologic function and not clincial outcome.
Description of Study Protocol:
  • 11 randomized, controlled trials (published in peer-reviewed journals) evaluating the use of enteral nutritional support supplemented with combinations of key nutrients vs. standard enteral nutrition, in a total of 1009 patients with a critical illness.
  • Articles obtained by reviewing reference lists in relevant publications and by manual and computer (Medline) searches of published articles from 1990 to Feb 1998.
  • Two reviewers independently abstracted the data from publications and differences were agreed by consensus.
  • Intent-to-treat analyses for these outcome measures were undertaken. A subgroup of patients undergoing surgery for GI cancer was also analyzed separately.
  • Tests for heterogeneity were performed.
Data Collection Summary:
  • Major infectious complications (wound infection, intrabdominal abscess, pneumonia, septicemia)
  • Nosocmial pneumonia alone
  • Death
  • Effects of the enteral nutritional support on rehabilitation time (time spent in the hospital or intensive therapy unit).
Description of Actual Data Sample:
  • 11 randomized, control trials with 966 patients.
  • Most of the studies evaluated the effects of Impact vs. a standard diet.
  • Two evaluated Immun-Aid vs. Standard diet.
  • 1 study - the experimental diet with enriched with L-arginine and L-glutamine.
  • 7 studies - the control and experimental diet were isonitrogenous and isocaloric.
  • 3 studies – the N content of experimental diet was higher than that of the control.
Summary of Results:

 

Infectious complications

  • 9 studies – overall Odds Ratio (OR) for risk of developing major infectious complications was 0.47 (95% CI 0.32 to 0.70; chi square test for heterogeneity 7.50, p=NS).
    • Therefore the supplemented nutritional support was associated with a significant and substantial decrease in the risk of developing infectious complications.
  • 6 studies – (497 pt with GI cancer) the overall OR for the risk of developing major infectious complications was 0.47 (95% CI 0.30 to 0.73; chi square for heterogeneity 3.55, p=NS).
    • Therefore the use of supplemented nutritional support in postoperative period in pt undergoing surgery for GI cancer was associated with significant decrease in the risk of developing infectious complications.

 

Nosocomial pneumonia

  • 8 studies – OR for the risk of developing nosocomial pneumonia was 0.91 (95% CI 0.53 to 1.56, chi square for heterogeneity 7.5, p=NS).
    • Therefore, use of supplemented nutritional support was not associated with significant decrease in risk of developing nosocomial pneumonia.
  • 4 studies with upper GI cancer – OR for the risk of developing nosocomial pneumonia was 0.71 (95% CI 0.32 to 1.69, chi square for heterogeneity 6.1, p=NS).
    • Therefore, use of supplemented nutritional support in postoperative period in pts undergoing surgery for GI cancer was not associated with significant decrease in risk of developing nosocomial pneumonia.

 

Death rate

  • 11 studies – OR for death was 1.77 (95% CI 1.00 to 3.12; chi square for heterogeneity 3.32, p=NS).
    • Use of supplemented nutritional support was not associated with a significant decrease in the risk of death.
  • 6 studies with GI cancer – OR for death was 1.53 (95% CI 0.44 to 5.372; chi square for heterogeneity 2.28, p=NS).
    • Use of supplemented nutritional support was not associated with a significant decrease in the risk of death.

 

Effect on hospital stay

  • 8 studies – The mean difference in hospital stay for all studies was a significant reduction of 2.5 days in pt receiving targeted nutrition (95% CI 4.0 to 1.0 days; chi square test for heterogeneity 4.73, p=NS).
  • 4 studies reported ICU stay was no significant difference in ICU stay between pts receiving targeted nutrition or standard control.
  • 6 studies with GI cancer – there was a significant reduction of 2.4 days in hospital stay for the targeted nutrition group (95% CI 4.0 to 0.8 days; chi square test for heterogeneity 1.91, p=NS).

 

 

 

Author Conclusion:
  • Our analysis showed that the administration of enteral nutritional support supplemented with key nutrients to critically ill patients significantly reduces the incidence of major infectious complications (major wound infections, pneumonia intraabdominal abscess, septicemia).
  • A similar reduction was also demonstrated in patients with GI cancer who received the nutritional support I the postoperative period. However when the risk of developing pneumonia alone was examined, there was no significant benefit in patients receiving supplemented nutritional support.
  • When the effects of supplemented nutritional support on death were examined, no significant difference was detected in patients receiving this or a standard nutritional regimen although there was a trend toward an increased risk of death in patients receiving supplemented nutrition.
  • However, a major part of the weighting for this analysis was from the study by Bower et.al., where there were more than twice as many deaths in patients receiving supplemented nutritional support. The pt in the supplemented group has significantly higher APACHE II score than the patients receiving standard enteral nutrition.
Funding Source:
University/Hospital: University of Aberdeen
Reviewer Comments:
Inclusion and exclusion criteria not clearly stated.
Quality Criteria Checklist: Review Articles
Relevance Questions
  1. Will the answer if true, have a direct bearing on the health of patients? N/A
  1. Will the answer if true, have a direct bearing on the health of patients? N/A
  2. Is the outcome or topic something that patients/clients/population groups would care about? N/A
  2. Is the outcome or topic something that patients/clients/population groups would care about? N/A
  3. Is the problem addressed in the review one that is relevant to dietetics practice? N/A
  3. Is the problem addressed in the review one that is relevant to dietetics practice? N/A
  4. Will the information, if true, require a change in practice? N/A
  4. Will the information, if true, require a change in practice? N/A
 
Validity Questions
  1. Was the question for the review clearly focused and appropriate? N/A
  1. Was the question for the review clearly focused and appropriate? N/A
  2. Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described? N/A
  2. Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described? N/A
  3. Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased? N/A
  3. Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased? N/A
  4. Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible? N/A
  4. Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible? N/A
  5. Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined? N/A
  5. Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined? N/A
  6. Was the outcome of interest clearly indicated? Were other potential harms and benefits considered? N/A
  6. Was the outcome of interest clearly indicated? Were other potential harms and benefits considered? N/A
  7. Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described? N/A
  7. Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described? N/A
  8. Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included? N/A
  8. Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included? N/A
  9. Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed? N/A
  9. Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed? N/A
  10. Was bias due to the review's funding or sponsorship unlikely? N/A
  10. Was bias due to the review's funding or sponsorship unlikely? N/A