• Doig GS. Evidence-based guidelines for nutritional support of the critically ill: results of a bi-national guideline development conference. Carlton (Australia): Australian and New Zealand Intensive Care Society (ANZICS); 2005. 282 p. [387 references]

This is the current release of the guideline.

Critical illness that would normally or usually require care in an intensive care unit

Assessment of Therapeutic Effectiveness
Management

Critical Care
Nutrition

Advanced Practice Nurses
Dietitians
Nurses
Physician Assistants
Physicians

To develop or update and validate an evidence-based feeding guideline for critically ill patients

Critically ill patients who would normally or usually be cared for in an intensive care unit for two days or longer

1. Enteral nutrition vs. standard care
2. Early enteral nutrition (<24 hours) vs. delayed enteral nutrition
3. Parenteral nutrition compared to standard care
4. Parenteral nutrition compared to enteral nutrition
5. Parenteral nutrition compared to early enteral nutrition (<24 hours)
6. Parenteral nutrition compared to delayed enteral nutrition
7. Gastric vs. post-pyloric enteral nutrition.
8. Use of prokinetics
9. Enteral nutrition and parenteral nutrition compared to enteral nutrition alone
10. Enteral nutrition supplemented with arginine compared to standard enteral nutrition (considered but no recommendation made)
11. Enteral nutrition supplemented with arginine vs parenteral nutrition (considered but no recommendation made)
12. Parenteral nutrition with glutamine vs. standard parenteral nutrition
13. Enteral nutrition with glutamine vs. standard enteral nutrition
14. Hypocaloric (Dose) of parenteral nutrition
15. Parenteral nutrition composition - Branched Chain Amino Acid (BCAA) content: High BCAA (>40%) vs. Low (<27%) content (considered but no recommendation made)

Mortality

Hand-searches of Published Literature (Primary Sources)
Hand-searches of Published Literature (Secondary Sources)
Searches of Electronic Databases

An extensive literature search was conducted for controlled trials of feeding interventions conducted in critically ill patients. Terms were also specified to identify methodologically rigorous guidelines, overviews, and meta-analyses. A complete listing of search terms is available from the guideline developer on request. On-line searching of Medline and EMBASE, and hand searching the reference lists of retrieved review papers, was undertaken. Recognised experts and industry were contacted for additional references. The final close-out date for this search process was April 2003.

Medline was searched using the PubMed search engine from 1966 to April 2003. EMBASE was searched using OVID from 1980 to April 2003.

The reference lists of several review articles were hand searched. For a complete list see the original guideline document.

Although the literature search itself was not limited to the identification of non-English language publications, the review process focused on English language publications only. Similarly, only studies published full-paper format that could be adequately critically appraised were considered for review.

The Medline/EMBASE search retrieved 2,287 abstracts. Independent review of all abstracts identified approximately 465 papers that may have been controlled trials or review papers on the topic of interest. All 465 papers were retrieved. Review of these 465 papers identified 337 primary studies that evaluated feeding interventions. Detailed review or critical appraisal of the 337 identified primary studies revealed 111 primary feeding studies that were conducted in critically ill patients and reported clinically meaningful outcomes. All 111 were appraised in detail to determine validity.

In addition the literature search identified one evidence-based guideline for nutritional support in the intensive care unit that had previously been validated in a cluster randomised trial.

Weighting According to a Rating Scheme (Scheme Given)

Levels of Evidence

Level I: adequately powered* (low false +ve or false -ve), well conducted trials

Level II: small, under-powered (high false +ve and false -ve), well conducted trials

Level III**: non-randomised concurrent (contemporary) controls

Level IV**: non-randomised historical controls

Level V**: case series without controls

*The guideline developers defined power as a measure of the probability that a clinical trial will detect a treatment effect of a given magnitude (X), under the assumption that the treatment effect actually exists. To qualify as a Level I trial (adequately powered), the trialists must have established that it was plausible to assume that the treatment effect of magnitude X actually existed. Data from earlier trials is the best way to establish the plausibility of the magnitude of the expected treatment effect (Halpern, S.D., Karlawish, J.H., and Berlin, J.A. [2002]. The continuing unethical conduct of underpowered clinical trials. JAMA 288, 358-362).

** These Levels of Evidence were not considered at this guideline conference.

Meta-Analysis of Randomized Controlled Trials
Review of Published Meta-Analyses
Systematic Review

Fixed effects meta-analysis using the odds ratio metric. Heterogeneity was assessed using the I² method.

Expert Consensus (Consensus Development Conference)

Grades of Recommendations

A+: More than one well conducted, adequately powered randomized controlled trial (RCT) with consistent results between studies (no heterogeneity), Level of Evidence Required: I

A: At least one well conducted, adequately powered RCT, Level of Evidence Required: I

A-: More than one well conducted, adequately powered RCT with inconsistent results (heterogeneity) between studies, Level of Evidence Required: I

B+: More than one well conducted RCT with consistent results between studies, Level of Evidence Required: II

B: At least one well conducted RCT, Level of Evidence Required: II

B-: More than one well conducted RCT with inconsistent results (heterogeneity) between studies, Level of Evidence Required: II

A formal cost analysis was not performed and published cost analyses were not reviewed.

Clinical Validation-Pilot Testing

The final ratified guideline was evaluated in a 27 hospital cluster randomised trial conducted in Australia and New Zealand.

The levels of evidence (I-IV) and grades of recommendations identifying the type of supporting evidence (A+, A, A-, B+, B, B-) are defined at the end of the "Major Recommendations" field.

The following evidence-based recommendations were ratified at the guideline development conference.

• Enteral Nutrition (EN) in preference to Standard Care (nothing by mouth [NPO]), Grade B+ recommendation

  5 Level II randomized controlled trials (RCTs). Ratified by positive meta-analysis and validated evidence-based guideline (Algorithms for Critical Care Enteral and Parenteral Therapy [ACCEPT]).

• Early EN (<24 hours) in preference to delayed EN, Grade B recommendation

  3 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• Parenteral Nutrition (PN) in preference to Standard Care (Intravenous [IV] Glucose), Grade B recommendation

  5 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• Early EN (<24 hours) in preference to PN, Grade B recommendation

  6 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• Early PN (<24 hours) in preference to delayed (>24 hours) EN, Grade B+ recommendation

  5 Level II RCTs. Ratified by positive meta-analysis and validated evidence-based guideline (ACCEPT). The results of the meta-analysis supporting this evidence-based recommendation (EBR) have been published elsewhere.

• Post-pyloric feeding when gastric feeding not tolerated, Grade B recommendation

  8 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• Use of prokinetics when gastric feeding not tolerated, Grade B recommendation

  5 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• EN supplemented with PN if 80% of goals not met with EN alone (after attempts at postpyloric feeding and use of prokinetics) by 72 hours, Grade B recommendation

  4 Level II RCTs. Ratified by validated evidence-based guideline (ACCEPT).

• PN with glutamine vs. standard PN, Grade B- recommendation

  4 Level II RCTs. Ratified by meta-analysis, heterogeneity present.

  Glutamine may be beneficial in select patients. To identify which patients may benefit, each constituent RCT should be reviewed and clinical judgement should be exercised.

• Management of diarrhoea, Grade B recommendation

  Ratified by validated evidence-based guideline (ACCEPT).

• Gastric residual values and tolerance, Level B evidence

  Ratified by validated evidence-based guideline (ACCEPT).

Definitions:

Levels of Evidence

Level I: adequately powered* (low false +ve or false -ve), well conducted trials

Level II: small, under-powered (high false +ve and false -ve), well conducted trials

Level III**: non-randomised concurrent (contemporary) controls

Level IV**: non-randomised historical controls

Level V**: case series without controls

*The guideline developers defined power as a measure of the probability that a clinical trial will detect a treatment effect of a given magnitude (X), under the assumption that the treatment effect actually exists. To qualify as a Level I trial (adequately powered), the trialists must have established that it was plausible to assume that the treatment effect of magnitude X actually existed. Data from earlier trials is the best way to establish the plausibility of the magnitude of the expected treatment effect (Halpern, S.D., Karlawish, J.H., and Berlin, J.A. [2002]. The continuing unethical conduct of underpowered clinical trials. JAMA 288, 358-362).

** These Levels of Evidence were not considered at this guideline conference.

Grades of Recommendations

A+: More than one well conducted, adequately powered randomized controlled trial (RCT) with consistent results between studies (no heterogeneity), Level of Evidence Required: I

A: At least one well conducted, adequately powered RCT, Level of Evidence Required: I

A-: More than one well conducted, adequately powered RCT with inconsistent results (heterogeneity) between studies, Level of Evidence Required: I

B+: More than one well conducted RCT with consistent results between studies, Level of Evidence Required: II

B: At least one well conducted RCT, Level of Evidence Required: II

B-: More than one well conducted RCT with inconsistent results (heterogeneity) between studies, Level of Evidence Required: II

Algorithms are provided in the original guideline document for:

• Intensive care unit feeding
• Addressing tube feeding associated diarrhea

The type of supporting evidence is identified and graded for each recommendation (see "Major Recommendations" field).

When evaluated in a cluster randomised trial including 499 patients from 14 hospitals, the adoption of this guideline resulted in a 10% reduction in mortality (p = 0.058) and an average decrease in hospital stay of 10 days (p = 0.003).

Not stated

Expected intensive care unit (ICU) length of stay less than 2 days. Expected or scheduled return to oral intake in less than 2 days.

Some of the critical appraisal summaries included in the original guideline document in the section titled "randomized controlled trials (RCTs) excluded due to major methodological flaws" may appear incomplete. In these randomized controlled trials, the major flaw that was detected was considered so significant that it precluded the trial from consideration in the guidelines development process and thus the appraisal of other issues was considered unnecessary.

A detailed implementation strategy is available from the guideline developer (see the "Availability of Companion Documents" field in this summary).

Getting Better
Living with Illness

Effectiveness

• Doig GS. Evidence-based guidelines for nutritional support of the critically ill: results of a bi-national guideline development conference. Carlton (Australia): Australian and New Zealand Intensive Care Society (ANZICS); 2005. 282 p. [387 references]

Not applicable: The guideline was not adapted from another source.

2005

Australian & New Zealand Intensive Care Society - Private Nonprofit Organization

Australian & New Zealand Intensive Care Foundation

ANZICS CTG Feeding Investigators Group

Primary Authors: Gordon S. Doig, Senior Lecturer in Intensive Care, Northern Clinical School, University of Sydney; Fiona Simpson, Clinical Associate Lecturer, Human Nutrition Unit, School of Molecular and Microbial Biosciences, University of Sydney

Not stated

This is the current release of the guideline.

None available

This NGC summary was completed by ECRI on October 11, 2005. The information was verified by the guideline developer on October 18, 2005.

This summary is based on the original guideline, which is subject to the guideline developer's copyright restrictions.