LB013 - PRIORITIZING INDIRECT CALORIMETRY ASSESSMENT OF CRITICALLY ILL ADULTS

LB013

PRIORITIZING INDIRECT CALORIMETRY ASSESSMENT OF CRITICALLY ILL ADULTS

J. Schulz^1,*, M. Brown¹, W. Dahl²

¹Food and Nutrition, University of Florida Health, ²Food Science and Human Nutrition, University of Florida, Gainesville, United States

Rationale: Although indirect calorimetry (IC) is the gold standard for assessing resting energy expenditure (REE), its routine use in all critically ill patients is often impractical, and thus, insight into prioritization of IC resources and appropriate weight-based energy estimations for use in the absence of IC is needed. This study explored how weight-based estimations performed compared to REE measured by IC in patient subpopulations and which patient characteristics were associated with REE overestimation.

Methods: In a tertiary care facility with 240 intensive care unit (ICU) beds, a retrospective chart review of critically ill adults (>18 years) assessed by IC (Q-NRG+, Baxter) from June 2023 to May 2025 was conducted. Measured REE (mREE) by IC (n=169) was compared to REE estimated by predictive equations and kcal/kg guidelines. Statistical modeling was conducted to determine which patient characteristics most contributed to poor REE prediction.

Results: As expected, predictive equations (Mifflin-St. Jeor, Harris-Benedict, and Penn State) performed poorly for REE prediction. Compared to the commonly recommended range of 25-30 kcal/kg, most (93%) non-obese Neuro ICU patients (excluding traumatic brain injury) measured 20-25 kcal/kg actual body weight (ABW), and 58% of all stroke patients measured 10-15 kcal/kg ABW. A majority of (86%) obese trauma patients measured over 30 kcal/kg ideal body weight (IBW). Most (85%) patients with decompensated cirrhosis measured below the recommended range of 30-35 kcal/kg ABW. Modeling of all patients showed that characteristics of BMI < 25, ≥ 51 years, and severe malnutrition most contributed to REE overestimation by dietitians.

Conclusion: In conclusion, mREE differed from estimated REE based on predictive equations and weight-based guidelines. Further research is needed to confirm patient characteristics contributing to REE overestimation and which patients would benefit most from IC.

Disclosure of Interest: None declared