Preliminary evidence for a medical nutrition therapy protocol: enteral feedings for critically ill patients.

The objective of this study was to evaluate the evidence behind specific but common patient care decisions in support of enteral feedings for patients admitted to intensive care units. Six specific questions were developed and refined to address clinical outcomes specific to clinical practice decisions pertinent to enteral feeding of critically ill patients. The data sources consisted of an intensive literature review from five databases, using standardized search terms. Randomized controlled clinical trials, meta-analyses, consensus statements, reviews, US Food and Drug Administration alerts, and case reports were selected for study. Research reports were abstracted in detail and evaluated for research quality using the criteria developed by the American Dietetic Association. Consensus statements regarding the influence of specific enteral feeding methods on key clinical outcomes (ie, infectious complications, cost, length of hospital stay, and mortality) were developed and graded based on the quality of the available evidence. The data support the use of enteral over parenteral nutrition to reduce infectious complications and cost, and the initiation of enteral feedings within 24 to 48 hours of injury or admission to an intensive care unit to reduce infectious complications and length of hospital stay in head injury and trauma patients. Postpyloric tube placement is associated with reduced gastric residual volume and reflux, but adequately powered trials are not available to support prevention of aspiration pneumonia. Acceptance of gastric residual volumes of up to 250 mL may increase volume of formula delivered. Promotility agents are associated with reduced gastric residual volume. Feeding patients in the semirecumbent rather than supine position is associated with reduced aspiration pneumonia and pharyngoesophageal formula reflux. Actual delivery of 14 to 18 kcal/kg/day or 60% to 70% of goal is associated with improved outcomes, whereas greater intake may not be in some populations. Blue food coloring should not be used with enteral feedings due to its limited sensitivity for aspiration and some risk of mortality. Well-designed, adequately powered, randomized controlled clinical trials are needed to evaluate any benefit of tube tip position on aspiration pneumonia or mortality, and of early enteral feedings on mortality.