Principles of the measurement of energy expenditure
Thorin, D.; Chiolero, R.
Agressologie Revue Internationale de Physio-Biologie et de Pharmacologie Appliquees Aux Effets de l'Agression 31(1): 59-61
1990
ISSN/ISBN: 0002-1148 PMID: 2363484 Document Number: 349254
Numerous methods can be used to assess energy expenditure (EE). The Fick method allows an easy calculation of EE in critically ill patients with Swan-Ganz catheters. Indirect calorimetry can be performed using either closed circuit or open circuit techniques. The latter is accurate when the patient is breathing air or low-FiO2 gaz mixture, but inaccurate at high FiO2. The accuracy of instruments, the presence of a leak-free system and the mathematical manipulations are critical points. Calorimetric studies performed in patients receiving high FiO2 must be interpreted with caution.