November/December 2016

New Guidelines on Nutrition Support for the Critically Ill
By Mandy L. Corrigan, MPH, RD, CNSC, FAND
Today's Geriatric Medicine
Vol. 9 No. 6 P. 8

In February, the Society of Critical Care Medicine (SCCM) and the American Society for Parenteral and Enteral Nutrition (ASPEN) released an update to the 2009 nutrition guidelines for critically ill patients.1 Nutrition support clinicians have been awaiting the new guidelines, which were published in the Journal of Parenteral & Enteral Nutrition.

The guidelines, consensus recommendations from SCCM and ASPEN and drawn from current research, are designed to guide the care of critically ill patients requiring nutrition support. They focus on adult patients in surgical or medical ICUs who are expected to remain in the ICU beyond the span of 48 to 72 hours.

Although various ICU nutrition topics are discussed in the 2009 and current edition, the new guidelines expound on specific patient conditions such as organ failure, pancreatitis, surgical populations, open abdomen and sepsis, the chronically critically ill, and management of obese patients. The new guidelines are intended to reach physicians, nurses, pharmacists, and dietitians to improve their roles in caring for the nutritional needs of these patient populations. It's important for members of the geriatric care team in acute care settings to become familiar with the updated guidelines and the evidence that supports their recommendations. This article discusses some of the highlights, changes, and new additions to the guidelines.

Evaluating the Research to Form the New Guidelines
The authors make it clear that the guidelines don't ensure beneficial outcomes and shouldn't take the place of making clinical judgments and decisions based on patients' individual medical needs. While it's important to know what the research says, clinicians, as part of the medical team, should base decisions individual patients' needs.

The research studies the authors reviewed and included in the analysis were published before December 31, 2013. However, the authors mention studies published after this cutoff date in the discussion sections within the guidelines.

The way the authors evaluated the quality of the research in 2009 differed from the way in which they evaluated it to develop the updated guidelines. Authors used a method called GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) to assess research quality. When the way in which certain studies were designed made the use of GRADE impossible, the authors made suggestions based on consensus and expert opinion.

What's New in the Guidelines?
Nutrition Risk Determination
Both the 2009 and 2016 guidelines for critically ill patients state that screening for nutrition risk should be completed on every ICU patient, but the concept of addressing both nutrition status and disease severity is a new recommendation based on expert opinion that's included in the update. Screening tools for determining nutrition risk include the nutritional risk screening (NRS 2002) or the NUTRIC (Nutrition Risk in Critically Ill) score to establish high or low nutrition risk. Because hospitals across the United States haven't previously had a standardized nutrition risk assessment tool, their methods varied widely. The concept of linking disease severity with nutrition status has generated discussion among clinicians regarding the current methods of evaluating nutrition risk. "We haven't done NUTRIC score or NRS 2002 yet, but we've been discussing it," says Kris Mogensen, MS, RD, LDN, CNSC, team leader dietitian at Brigham and Women's Hospital in Boston.

The authors emphasize that surrogate biochemical markers such as albumin, prealbumin, retinol-binding protein, and transferrin aren't validated markers for assessing nutrition status. They agree that the outcome of nutrition screening in accordance with NRS 2002 or NUTRIC scores is associated with appropriate determination for initiating parenteral nutrition.

Gastric Residual Volumes
Over the years, the bedside practices of placing on hold enteral nutrition (EN) orders based on gastric residual volumes (GRVs) or measurements of stomach contents have varied. Typically, a nurse attaches a syringe to the end of the feeding tube, withdraws the contents of the stomach, and measures the volume. Unfortunately, the common practice of measuring GRVs as a way to assess tolerance to EN feeding isn't evidence based. The new guidelines recommend that for patients receiving EN, members of the geriatric care team do not use GRVs routinely, based on the evidence from three studies.2-4 Eliminating routine performance of GRVs has been shown to improve delivery of EN without compromising patient safety. Guideline authors include recommendations for monitoring tolerance to EN in place of administering routine GRVs.1

With the understanding that this represents a departure from historic ICU practice, the authors suggest that if GRVs are used, clinicians should not place EN orders on hold when the GRV is <500 mL.

"I do appreciate the authors recommending discontinuing the practice of routine GRV checks," says Stephanie Dobak, MS, RD, LDN, CNSC, a clinical dietitian at Thomas Jefferson University Hospital in Philadelphia. "They acknowledge it's a big practice change and therefore offer a threshold of 500 mL if GRVs continue to be checked. Our neurocritical care units are no longer routinely checking GRVs, saving nursing time and resources."

Enteral Formula Selection
The 2016 guidelines include new recommendations for selecting enteral formulas, endorsing the use of a standard polymeric formula for patients receiving EN in the ICU. Due to the high costs of specialty formulas and the insufficient or conflicting data on health outcomes with their use, the choice to use a polymeric formula is commonplace in many institutions. Much of the research on specialty formulas may not apply to all patient populations. And if providers use a product different from what was used in a particular study, patients may not experience the same results. Specialty enteral formulas vary slightly in composition from one another. "We are minimalists when it comes to specialty formulas for the most part, which is in line with the new guidelines," Mogensen says.

Studies on specialty formulas completed after the 2009 guidelines were released showed conflicting data on the use of enteral formulas containing omega-3 fish oils in acute respiratory distress syndrome and acute lung injury patients. The strong recommendation in 2009 to use omega-3 specialty enteral formulas has been downgraded, eliminating such a recommendation in the new guidelines. "The evidence to support disease-specific enteral tube feeding formulas [in these patients] just was not there," Dobak says.

One area in which specialty formulas were recommended was in postoperative surgical ICU patients requiring EN. The authors noted that immune-modulating enteral formulas needed to contain both fish oil and arginine, based on data showing a decrease in hospital length of stay and reduction in infections.

The authors discuss the importance of protein as the key macronutrient for ICU patients, suggesting the need to follow feeding protocols to increase the delivery of EN (eg, clinical algorithms promoting better initiation and delivery of nutrition, ways to troubleshoot problems), continuing EN in the presence of diarrhea until the cause is determined (eg, infectious, medication related), and achieving blood glucose levels between 150 and 180 mg/dL for the general ICU population.

Conclusion
The new 2016 guidelines will help members of the geriatric care team who work in ICUs incorporate evidence-based practices for routine patient care. Becoming familiar with and implementing these recommendations require a team approach and should be undertaken with the intention of monitoring outcomes to recalibrate nutrition practices.

— Mandy L. Corrigan, MPH, RD, CNSC, FAND, is a nutrition support clinician and consultant based in St. Louis.

References
1. McClave SA, Taylor BE, Martindale RG, 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 J Parenter Enteral Nutr. 2016;40(2):159-211.

2. Powell KS, Marcuard SP, Farrior ES, Gallagher ML. Aspirating gastric residuals causes occlusion of small-bore feeding tubes. JPEN J Parenter Enteral Nutr. 1993;17(3):243-246.

3. Poulard F, Dimet J, Martin-Lefevre L, et al. Impact of not measuring residual gastric volume in mechanically ventilated patients receiving early enteral feeding: a prospective before-after study. JPEN J Parenter Enteral Nutr. 2010;34(2):125-130.

4. Reignier J, Mercier E, Le Gouge A, et al. Effect of not monitoring residual gastric volume on risk of ventilator-associated pneumonia in adults receiving mechanical ventilation and early enteral feeding: a randomized controlled trial. JAMA. 2013;309(3):249-256.

IMPLEMENTING THE NEW GUIDELINES
When undertaking implementation of the new guidelines, consider the following:

• Understand the current nutrition practices within your institution, such as variations among practitioners/staff, units, outdated or gaps in practice, policies and procedures surrounding nutrition care and delivery of nutrition support.

• Identify barriers to implementing new practices.

• Look for opportunities to implement new practices. Keep in mind evaluation and outcomes when in the implementation phase. Administrators and physicians may plan to develop a method to track outcomes.

• Identify key stakeholders to obtain buy-in from across the interdisciplinary team.

• Collaborate with members of the interdisciplinary team to implement changes to patients' nutrition care. Gather members of the interdisciplinary team to discuss the guidelines, research, and educational needs within the institution, and brainstorm implementation strategies. Collaboration fosters a shared sense of accomplishment, varying viewpoints and ideas, and varying perspectives on nutrition care across disciplines.

• Identify colleagues who can be "change agents" to help promote evidence-based practices.

• Consider using a variety of educational strategies.

• Develop educational strategies and consider the ongoing educational needs for new employees.

• Use active dissemination and implementation rather than passive methods. Active methods can include the work of champions and opinion leaders to spread knowledge, enlist support, and offer leadership to change a practice or initiate a new practice, provide education across many settings with a variety of instructional methods, and target interventions to overcome possible barriers. Passively handing out information on nutrition guidelines or posting information on a web page doesn't educate team members as effectively or lead to changes in practice.

• Share with colleagues outside of your institution the best practices for implementation.

— MLC