CI: Introduction (2012)

CI: Introduction (2012)

Guideline Overview

Guideline Title

Critical Illness (2012) Evidence-Based Nutrition Practice Guideline

Guideline Narrative Overview

The focus of this guideline is on the nutrition care of the critically ill adult patient who requires nutrition support. The goals of nutrition support in well-nourished and malnourished critically ill patients are to minimize physiologic deterioration and promote anabolism and recovery. Clinical judgment is crucial in the application of this guideline.

Guideline Development

This guideline outlines the most current information on nutrition support practice in the critically ill patient. The recommendations developed in this guideline were based upon a systematic review of the literature in multiple practice areas. A summary of the evidence analysis is below:
Topics include:
  • Determining Resting Metabolic Rate
  • Enteral vs. Parenteral Nutrition
  • Initiation of Enteral Nutrition
  • Feeding Tube Site
  • Enteral Nutrition Energy Delivery
  • Blue Dye Use
  • Optimizing Enteral Nutrition Delivery
  • Immune-Modulating Enteral Nutrition
  • Enteral Nutrition and Fiber
  • Supplemental Enteral and Intravenous Glutamine
  • Hypocaloric, High Protein Feeding Regimen
  • Blood Glucose Control 
The number of supporting documents for these topics is below:
  • Recommendations: 22
  • Conclusion Statements: 136
  • Evidence Summaries: 116
  • Article Worksheets: 190.

At the time of this publication, the majority of research has been completed in the adult population; therefore, clinical judgment is crucial in the application of these guidelines for individuals in other age groups and settings.

Guideline Development

To learn about the Academy systematic review and guideline development and review process, visit the Policy and Process section. 

Application of the Guideline

This guideline will be accompanied by a set of companion documents (i.e., a toolkit) to assist the practitioner in applying the guideline. The toolkit will contain outcomes management tools, resources and case studies. The toolkit is currently under development and will undergo pilot-testing through the Academy of Nutrition and Dietetics Dietetic Practice-Based Research Network prior to publication.


All Academy guidelines are revised every five years. The literature search will begin for each guideline topic three years after publication to identify new research that has been published since the previous search was completed. An expert work group will convene to determine the need for new and revised recommendations.

Medical Nutrition Therapy and Critical Illness

Medical and surgical conditions where the critical illness guideline may apply include those in which the patient requires care in an intensive care unit (ICU), such as:

  • Sepsis and systemic inflammatory response syndrome (SIRS)
  • Trauma
  • Neurological injury such as traumatic brain injury, stroke, ALS, etc.
  • Pancreatitis
  • Respiratory failure
  • Multi-organ failure
  • Surgery.

New research may warrant a revision to a specific question or recommendation prior to the full project or guideline revision. Once identified, information is gathered and the EAL oversight committee will make a decision on the appropriately action.

Populations to Whom This Guideline May Apply

Scientific evidence supports the importance of the Registered Dietitian (RD) as a member of the interdisciplinary team caring for critically ill adults.

The RD plays an integral role on the interdisciplinary care team by determining the optimal nutrition prescription and developing the nutrition care plan for critically ill patients in all phases of illness. Based on the patient’s clinical status, plan for treatment, comorbidities,  the dietitian monitors and evaluates the effectiveness of the nutrition care plan in promoting the patient’s nutritional health and quality of life. The dietitian adjusts the nutrition care plan as necessary to achieve desired outcomes.

Study Limitations

Some ICU studies are limited by small sample size or the lack of statistical power analyses. These limitations may be reflected in statements made in reviewing evidence summaries, conclusions and associated grades of evidence. Performing power analysis and sample size estimation is an important aspect of designing a research study,  because without these calculations, the number of subjects recruited for a specific research question may be too few. When the sample size is too small, the study will lack the precision to provide reliable answers to the questions it is investigating.

Power is broadly defined as the probability that a test having statistical significance will reject the null hypothesis for a specified value of an alternative hypothesis. Stated more simply, power may be defined as the ability of a test to detect an effect, given that the effect actually exists.

Other Guideline Overview Material

For more details on the guideline components, use the links on the left to access:
  • Scope of Guideline
  • Statement of Intent and Patient Preference
  • Guideline Methods
  • Implementation of the Guideline
  • Benefits and Harms of Implementing the Recommendations.


This guideline should not be used when aggressive medical care is no longer desired. The appropriateness of a clinical intervention involves a substantial element of personal choice or values of the patient, which includes advance directives. Although nutrition support is often warranted for the critically ill patient, occasionally, support may be contraindicated due to the patient's clinical status or patient preference. Therefore, a comprehensive nutrition assessment and ongoing reassessment is necessary to determine whether the initiation or continued provision of support is appropriate.

  1. Vrees MD, Albina JE. Metabolic response to illness and its mediators. Clinical Nutrition: Parenteral Nutrition, Rombeau JL, Rolandelli RH (eds). WB Saunders, Philadelphia, 2000, pp. 21, 034.
  2. A.S.P.E.N. Board of Directors: Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients.J Parenter Enteral Nutr. 26 (suppl) 1S, 2002.
  3. Compher C. Frankenfield D. Keim N, Roth-Yousey L. for the Evidence Analysis Working Group. Best practice methods to apply to measurement of resting metabolic rate in adults: a systematic review. J Am Diet Assoc. 2006; 106: 881-903.