Assessment of energy expenditure and CO₂ production with different enteral feeds

The aim of the study is to consider to which extent the production of CO₂ (V_CO2) and the resting energy expenditure (REE) are influenced by overfeeding and to which extent by the composition of enteral nutrition.

Five male and four female patients with Crohn's disease in remission were enrolled. REE and V_CO2 were measured using the method of indirect calorimetry. The measurements were performed under hospitalization in the morning after 10 hours fasting in four modifications: I. high sugar (60%) in dose 1.2 × REE; II. high sugar (60%) and high-energy supply (2.4 × REE); III. high fat (60%) in dose 1.2 × REE; IV. high fat (60%), high energy (2.4 × REE). Between measurements there was a time interval of 7–10 days, when patients were only on home enteral nutrition.

Results did not differ depending on the different composition of nutrition in the case of adequate energy supply I. (REE = 1438 ± 264.1 kcal/24 hours, V_CO2 = 179.1 ± 31.6 ml/min) × III. (REE= 1431 ± 342.7, V_CO2 = 190 ± 54.2), likewise upon overfeeding II. (REE = 1674 ± 389.6, V_CO2 = 218 ± 52.0) × IV. (REE= 1661 ± 378.7, V_CO2 = 202 ± 42.3). In the high-sugar (60%) diet the overfeeding increased REE (P < 0.05) and V_CO2 (P < 0.01) (I. × II.). In the high-lipid (60%) diet the overfeeding increased REE (P < 0.01) but not V_CO2 (III. × IV.)

Conclusion

Excessive energy supply results in higher V_CO2 and in higher REE in comparison with adequate food intake. However, the nutrition with high content of fat does not lead upon overfeeding to significant increase of CO₂ production. The composition of the nutrition with appropriate energy amount does not significantly influence V_CO2 and the REE.