Weight-Based Ordering: An Evaluation of Increased Guideline Use in Hospital Total Parenteral Nutrition Dosing

Background: In the past, parenteral nutrition in the Calgary Health Region was ordered as volumes of standard solutions, which limited individualization. Ordering total parenteral nutrition (TPN) that falls within macronutrient dosing guidelines may minimize complications associated with TPN, such as hyperglycemia, azotemia, hepatic steatosis, or continued malnutrition and catabolism. The Foothills Medical Centre in Calgary changed to a weight-based ordering system for TPN in 1999. This study's purpose was to determine if this change increased adherence to TPN dosing guidelines. Methods: Macronutrient doses in TPN solutions ordered as standard solutions were compared with those ordered by weight. Mean protein, dextrose, lipid, and kilocalorie doses and the number of orders deviating from guidelines were examined. Results: Weight-based dosing showed a significant reduction in deviation from guidelines for kilocalorie dose compared with TPN ordered as standard solutions. There also was a significant increase in mean protein dose and reductions in mean dextrose load and mean kilocalorie dose in the weight-based TPN group only, suggesting these changes were caused by the change in ordering method. Conclusions: Overall, weight-based ordering increased adherence to TPN dosing guidelines. The study did not have the statistical power to show significant differences between weight-based or standard TPN dosing; however, several trends were shown.