Titre du Document

Factors affecting the measurement of energy expenditure during energy balance studies in preterm infants

PERRING Jeffrey ; HENDERSON Marjorie ; COOKE Richard J.

Our objective was to examine factors that affect the accuracy of energy expenditure measurements (EE), when using flow-through indirect calorimetry (IC), to determine the minimum length of time needed to measure 24- and 48-h EE and to compare cross-over and parallel designs as methods of investigation during energy balance collections (EB) in preterm infants. A baby doll manikin was used to determine equilibration times and to compare VCO_{2} and VO_{2} as measured by flow meter and indirect calorimetry under different study conditions, one of which simulated an EB. Continuous EE was measured to determine the minimum length of time needed to accurately reflect 24- and 48-h EE and to compare parallel and cross-over studies as methods of study design in a group of normal enterally fed preterm infants. The mean (±SD) errors between flow meter and indirect calorimetry determinations for VCO_{2} and VO_{2} were - 1.9 ± 2.5 and - 1.8 ± 4.3% under conditions that simulated an EB. Cumulative 6-h EE accurately predicted 24-and 48-h EE. Expressed in absolute terms (kcal/d), EE did not change on a day-to-day basis but did increase over the 2-wk study period. Expressed on body weight basis (kcal/kg/d), EE did not change on a day-to-day or week-to-week basis. The variance in EE due to biologic variability; i.e. the parallel design, was ∼6 times greater than that due to age, weight, and weight gain; i.e. the cross-over design. Indirect calorimetry, therefore, accurately me

Editeur

Lippincott Williams & Wilkins

Identifiant

PMID : 11004244 ISSN :

0031-3998
CODEN : PEREBL

Source

Pediatric research
A.

2000, vol. 48, n° 4, pp. 518-523 [bibl. : 31 ref.]

Langue

Anglais