Indications for Clinical Nutrition Types
Determining the Optimal Type of Clinical Nutrition Support
When nutritionally-at-risk patients are not able to gain sufficient nutrient intake from hospital food, fortified hospital food or diet, enteral nutrition (EN) including oral nutritional supplements or tube feeding via, nasogastric, nasoenteral or percutaneous tubes may be required to achieve clinical nutrition requirements.1
If EN intake is also determined to be insufficient, parenteral nutrition (PN) should be started as a supplement to, or replacement for enteral tube feeding in order to avoid disease-related malnutrition.2,3 PN is the intravenous administration of nutrients, bypassing the gastrointestinal (GI) tract.2
It is important to note that nutritional support is not restricted to the exclusive administration of EN or PN, but PN and EN may complement each other, e.g. with the use of PN plus minimal “trophic” enteral feeding or EN plus supplemental PN.4
The following chart illustrates the choice of nutrition support:
The following algorithm can be used for the correct enteral and/or parenteral route of administration:
When is EN Indicated?
The rule of thumb states that if the gut works, EN is indicated. In patients with a functioning gastrointestinal (GI) tract, EN is ideally started within 24 to 48 hours of intensive care unit (ICU) admission.5,6,7,8,9,10
When Is PN Indicated?
If EN is contraindicated or a limited tolerance for EN over a prolonged period does not allow sufficient intake to cover the patient’s entire nutritional needs, PN should be started to supplement or replace enteral tube feeding.2,3
- (Post-operative) paralytic and mechanical ileus
- Inflammatory bowel disease
- Enterocolitis (AIDS, chemo/radiation therapy)
- Intestinal resection (short bowel syndrome)
- High output fistula
- Burn injury
- Gastrointestinal (GI) cancer
- Immaturity (premature babies)
When Is Total PN Indicated?
In cases where EN is not tolerated, total PN can supply patients with all of their daily nutritional requirements.7 This route of nutrition is delivered either via a centrally or peripherally placed line.14
In order to prevent under-nutrition and related adverse effects, all ICU patients who are not expected to be on a full oral diet should first receive clinical nutrition, preferably EN within 24 to 48 hours of admission. However, EN alone is often insufficient in providing the required amount of energy and protein.4 This may result in nutritional deficits known to worsen clinical outcomes.15
When Is Supplemental PN Indicated?
Nutritional support is not restricted to the exclusive administration of EN or PN, but PN and EN can complement each other, such as with the use of PN plus minimal “trophic” enteral feeding or EN plus supplemental PN.4 In this approach, PN supplies only part of daily nutritional requirements, supplementing oral intake.
The European Society for Clinical Nutrition and Metabolism (ESPEN) has set guidelines for the use of supplemental PN in intensive care. Those guidelines state:10
Patients receiving less than their targeted enteral feeding after two to three days should be considered for supplemental PN to fill the caloric gap.
The following are contraindications of parenteral nutrition:12
- 1. Lochs H, Allison SP, Meier R et al. Introductory to the ESPEN Guidelines on Enteral Nutrition: Terminology, definitions and general topics. Clin Nutr 2006;25(2):180-186.
- 2. a. b. c. d. National Collaborating Centre for Acute Care (UK). Nutrition Support for Adults Oral Nutrition Support, Enteral Tube Feeding and Parenteral Nutrition. NICE Clinical Guidelines, No. 32 London 2006.
- 3. a. b. Kreymann KG. Early nutrition support in critical care: A European perspective. Curr Opin Clin Nutr Metab Care 2008;11:156-159.
- 4. a. b. c. Heidegger CP, Berger MM, Graf S et al. Optimization of energy provision with supplemental parenteral nutrition in critically ill patients: a randomized controlled clinical trial. Lancet 2013;381(9864):385-393
- 5. Heyland DK. Parenteral nutrition in the critically-ill patient: More harm than good? Proc Nutr Soc 2000;59:457-466.
- 6. Heyland DK, Dhaliwal R, Drover JW et al. Canadian clinical practice guidelines for nutrition support in mechanically ventilated, critically ill adult patients. JPEN 2003;27:355-373.
- 7. a. b. Gramlich L, Kichian K, Pinilla J et al. Does enteral nutrition compared to parenteral nutrition result in better outcomes in critically ill adult patients? A systematic review of the literature. Nutrition 2004;20:843-848.
- 8. Rubinsky MD, Clark AP. Early enteral nutrition in critically ill patients. Dimens Crit Care Nurs 2012;31:267-274.
- 9. McClave SA, Martindale RG, Vanek VW et al. Guidelines for the Provision and Assessment of Nutrition Support Therapy in the Adult Critically Ill Patient: Society of Critical Care Medicine (SCCM) and American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.). JPEN 2009;33:277-316.
- 10. a. b. Singer P, Berger MM, Van den Berghe G et al. ESPEN Guidelines on Parenteral Nutrition: intensive care. Clin Nutr 2009;28(4):387-400.
- 11. Löser C, Aschl G, Hebuterne X et al. ESPEN guidelines on artificial enteral nutrition-percutaneous endoscopic gastrostomy (PEG). Clin Nutr 2005;24:848-861.
- 12. a. b. Austrian Society of Clinical Nutrition (AKE). Recommendations for enteral and parenteral nutrition in adults. Vienna 2008/2010.
- 13. Rothaermel S, Bischoff SC, Bockenheimer-Lucius G et al. Ethical and legal points of view in parenteral nutrition - guidelines on parenteral nutrition. Chapter 12. Ger Med Sci 2009;7:Doc16.
- 14. Jauch KW, Schregel W, Stanga Z et al. Access technique and its problems in parenteral nutrition. - Guidelines on Parenteral Nutrition, Chapter 9. German Medical Science 2009;7:1-18.
- 15. Thibault R, Heidegger CP, Berger MM et al. Parenteral nutrition in the intensive care unit: cautious use improves outcome. Swiss Med Wkly 2014;144:w13997.