Can an adequate energy intake be able to reverse the negative nitrogen balance in mechanically ventilated critically ill patients?
OBJECTIVE
Adequate energy provision and nitrogen losses prevention of critically ill patients are essentials for treatment and recovery. The aims of this study were to evaluate energy expenditure (EE) and nitrogen balance (NB) of critically ill patients, to classify adequacy of energy intake (EI), and to verify adequacy of EI capacity to reverse the negative NB.


METHODS
Seventeen patients from an intensive care unit were evaluated within a 24-hour period. Indirect calorimetry was performed to calculate patient's EE and Kjeldhal for urinary nitrogen analysis. The total EI and protein intake were calculated from the standard parenteral and enteral nutrition infused. Underfeeding was characterized as EI 90% or less and overfeeding as 110% or greater of EE. The adequacy of the EI (EI EE(-1) × 100) and the NB were estimated and associated with each other by Spearman coefficient.


RESULTS
The mean EE was 1515 ± 268 kcal d(-1), and most of the patients (11/14) presented a negative NB (-8.2 ± 4.7 g.d(-1)). A high rate (53%) of inadequate energy intake was found, and a positive correlation between EI EE(-1) and NB was observed (r = 0.670; P = .007).


CONCLUSIONS
The results show a high rate of inadequate EI and negative NB, and equilibrium between EI and EE may improve NB. Indirect calorimetry can be used to adjust the energy requirements in the critically ill patients.
Japur
Camila C
CC
Division of Intensive Care, Department of Surgery and Anatomy, Faculty of Medicine of Ribeirão Preto-University of São Paulo, SP 14049-900 Ribeirão Preto, Brazil. camila@fmrp.usp.br
Monteiro
Jacqueline P
JP
Marchini
Júlio Sérgio
JS
Garcia
Rosa Wanda Diez
RW
Basile-Filho
Anibal
A
D000328:Adult; D000368:Aged; D002153:Calorimetry, Indirect; D003422:Critical Care; D016638:Critical Illness; D003430:Cross-Sectional Studies; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism; D002149:Energy Intake; D004734:Energy Metabolism; D004750:Enteral Nutrition; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000378:metabolism* / Q000652:urine; D010288:Parenteral Nutrition; D012121:Respiration, Artificial; D016896:Treatment Outcome
D004044:Dietary Proteins; D009584:Nitrogen