P566 - COMPARISON BETWEEN ESTIMATED AND MEASURED ENERGY REQUIREMENTS IN CRITICALLY ILL PATIENTS USING INDIRECT CALORIMETRY

P566

COMPARISON BETWEEN ESTIMATED AND MEASURED ENERGY REQUIREMENTS IN CRITICALLY ILL PATIENTS USING INDIRECT CALORIMETRY

 

G. Bernardes Yacoub^1,*, D. Toledo Oliveira¹, E. Giantomassi Paiva¹, F. Antunes Ribeiro¹, J. Reginas Moraes¹, J. Manoel Silva Jr¹

¹Hospital Israelita Albert Einstein, São Paulo, Brazil

 

Rationale: Accurate energy assessment in critically ill patients is essential, affecting recovery, mechanical ventilation duration, and mortality. Although predictive formulas (e.g., 25 kcal/kg) are widely used, they often lead to misestimations. Indirect calorimetry (IC) is the gold standard, enabling personalized nutrition. This study compares caloric needs estimated by prediction with those measured by IC.

Methods:  Retrospective analysis of critically ill patients undergoing IC (April–November 2022). Data included weight, BMI, age, sex, and energy expenditure (predicted by P × 25 kcal/kg vs. IC). Nutritional adequacy was assessed by caloric intake vs. measured needs. Statistical analysis used ANOVA and chi-square tests (p < 0.05).

Results: Among 154 patients (65 ± 18 years, 61% male), IC revealed higher energy needs (1892 ± 515 kcal/day) than predictions (1745 ± 412 kcal/day; p < 0.0001), with 32% underfed, 42% adequate, and 26% overfed. Underfed patients had lower BMI (23.2 ± 4.7 kg/m²) vs. overfed (28.6 ± 5.6 kg/m²; p < 0.0001). Age >70 correlated with underfeeding (41%); age <50 with overfeeding (34%; p = 0.001). Weight <60 kg showed the largest prediction error (−312 ± 198 kcal/day).

Conclusion: Predictive formulas often misestimate needs, underestimating in elderly/low-weight patients and overestimating in high-BMI cases. IC enables precise nutrition, reducing metabolic risks. These findings support IC’s broader use in critical care.

References: Singer P, et al. Clin Nutr. 2019;38:48–79.

Castro MG, et al. BRASPEN J. 2018;33(Supl 1):2–36.

Gupta RD, et al. Indian J Endocrinol Metab. 2017;21:594–599.

Delsoglio M, et al. J Clin Med. 2019;8(9):1387.

Boullata J, et al. J Am Diet Assoc. 2007;107:393–401.

Berger MM, et al. Clin Nutr. 2019;38:584–593.

Disclosure of Interest: None declared