An Exploratory Retrospective Study of Factors Affecting Energy Expenditure in Critically Ill Children

Abstract

Background Accurate measurement of energy expenditure is not widely available. Patient and clinical factors associated with energy expenditure have been poorly explored, leading to errors in estimation formulae. The objective of this study was to determine clinical factors associated with measured energy expenditure (MEE), expressed in kcal/kg/d, in critically ill children. Methods This was a retrospective study at 2 Canadian pediatric intensive care units (ICUs). Patients were mechanically ventilated children who had 1 or more MEE using indirect calorimetry. Associations between MEE and 28 clinical factors were evaluated in univariate regression and 16 factors in a multivariate regression model accounting for repeated measurements. Results Data from 239 patients (279 measurements) were analyzed. Median (Q1, Q3) MEE was 34.8 (26.8, 46.2) kcal/kg/d. MEE was significantly associated with weight, heart rate, diastolic blood pressure, ICU day of indirect calorimetry (P = 0.004), minute ventilation, vasoactive inotropic score (P = 0.004), opioids, chloral hydrate, dexmedetomidine, inhaled salbutamol (P = 0.02), and propofol dose (all P < 0.0001 unless otherwise specified) in the final multivariate regression model. Conclusions This study demonstrated association between MEE (kcal/kg/d) and factors not previously explored in pediatric critical illness. Further evaluation of these factors to confirm associations and more precisely quantify the magnitude of effect is required to support refinement of formulae to estimate energy expenditure.

Nutritional Management of the Critically Ill Neonate

“…The finding of a change in energy needs during the first week of critical illness is relatively consistent with EE studies in critically ill children, which show that REE values gradually increase with the increasing length of ICU stay (<4, 4–7, and >7 days) (98), but also that EE is affected by other factors such as weight, temperature, heart rate, diastolic blood pressure, minute ventilation, and drugs (98,99).…”

Determining energy and protein needs in critically ill pediatric patients: A scoping review

“…Most studies have reported a positive association between body temperature and EE. Day in the PICU was not correlated with EE in the systematic review, 5 similar to a recent study, 32 whereas a positive correlation was observed in another study 52 …”

“…Similar to this systematic review, three recent studies 34,35,52 observed a positive association between weight and EE in children. One study found a positive association between age and EE 34 …”

“…5 Based on at least two evaluations, factors in children that were positively correlated with EE included T A B L E 1 Findings related to subquestion 1a: Measurement methods of EE in critically ill pediatric patients. Similar to this systematic review, three recent studies 34,35,52 observed a positive association between weight and EE in children. One study found a positive association between age and EE.…”

“…Day in the PICU was not correlated with EE in the systematic review, 5 similar to a recent study, 32 whereas a positive correlation was observed in another study. 52 Among recent studies, one study 52 also showed that neuromuscular blockers and sedatives had a negative association with EE in critically ill pediatric patients, and three studies did not find an association. 32,35,53…”