Dépense énergétique en réanimation

The exact proportion of energy expenditure that should be provided to an intensive care unit (ICU) patient is still debated. However, because gross under- or over-feeding is harmful nutritional support should be based on an accurate assessment of energy expenditure. The determinants of energy expenditure in ICU patients include injury and disease, body composition and treatments such as nutritional support or mechanical ventilation. Indirect calorimetry remains the reference method for measuring energy expenditure but equipment cost, insufficient technical expertise and various conditions present in ICU patients limit its application. Conversely, traditional estimations of energy expenditure from predicted basal metabolic rate plus a 'stress factor' are highly inaccurate. However, new predictive multiparameter equations permit practical and relatively accurate estimation of energy expenditure that is necessary for routine practice. Moreover, the assessment of energy balance may have a particular significance in the nutritional management of the most critically ill patients. The further development of clinical tools for assessing body composition, especially body mass cell, could help to provide the relevance of the concept of optimal energy intakes in ICU patients.