JPEN J Parenter Enteral Nutr. 2022 May 8. doi: 10.1002/jpen.2393. Online ahead of print.
ABSTRACT
BACKGROUND: Indirect calorimetry (IC) is the gold standard for measuring resting energy expenditure. Energy expenditure (EE) estimated by ventilator-derived carbon dioxide consumption (EEVCO2 ) has also been proposed. In the absence of indirect calorimetry predictive weight-based equations have been recommended to estimate daily energy requirements. This study aims to compare simple predictive weight-based equations with those estimated by EEVCO2 and indirect calorimetry in mechanically ventilated patients of Covid-19.
METHODS: Retrospective study of a cohort of adult critically ill COVID-19 patients requiring mechanical ventilation and artificial nutrition to compare energy estimations by three methods through the calculation of bias and precision agreement, reliability and accuracy rates.
RESULTS: In 58 mechanically ventilated patients, a total of 117 paired measurements were obtained. The mean estimated energy derived from weight-based calculations was 2576±469 kcals/24hours, as compared to 1507±499 kcal/24hours when estimation of EE by indirect calorimetry, resulting in a significant bias of 1069 kcal/day (95% CI (-2158 – 18.7 kcal); p < 0.001). Similarly estimated mean EEVCO2 was 1388±467 kcals/24hours, when compared with estimation of EE from indirect calorimetry, a significant bias of only 118 kcal/day (95% CI (-187 – 422 kcal); p < 0.001) compared by the Bland-Altman plot was noted.
CONCLUSION: The energy estimated with EEVCO2 correlated better with IC values, than energy derived from weight-based calculations. Our data suggests that the use of simple predictive equations may potentially lead to overfeeding in mechanically ventilated Covid-19 patients.
CLINICAL RELEVANCY STATEMENT: Both overfeeding and underfeeding of intensive care unit (ICU) patients are associated with worse outcomes. Ideally, the individual caloric target is based on the frequent assessment of energy expenditure (EE). Indirect calorimetry is considered the gold standard but is not always available. EE estimated by ventilator-derived carbon dioxide consumption (EEVCO2) derived from ventilator and stand-alone monitors has also been proposed as an alternative. Guidelines recommend predictive weight-based dosing when indirect calorimetry (IC) is not feasible to estimate daily energy requirements. This study was able to prove that guideline-recommended weight-based calculations overestimated the energy requirements and we were able to arrive at an energy estimation that can be closer to the EE with IC and EEVCO2 among COVID-19 patients. This study would help in standardizing the more commonly used weight-based calculations for energy estimation. This article is protected by copyright. All rights reserved.
PMID:35526145 | DOI:10.1002/jpen.2393
