Long‐term Measurements of Energy Expenditure in Severe Burn Injury

Abstract

The objective of this study was to evaluate resting energy expenditure (REE) in spontaneously breathing and artificially ventilated burn patients during the entire intensive care period. In 27 patients with 51 +/- 20% body surface area burned (BSAB) the REE was determined via indirect calorimetry. Three groups were formed according to the mortality prognosis index of Zawacki et al. In groups A, B, and C the predicted mortality rates were <20%, 20% to 80%, and >80%, respectively. The frequency of acute respiratory distress syndrome (ARDS), sepsis, renal failure, and mortality increased from group A toward group C. The REE test revealed wide individual variation and was usually overestimated by all tested formulas. The mean REE was comparable in groups A, B, and C during the first 20 days (49 +/- 16% vs. 59 +/- 21% vs. 57 +/- 18% above the REE calculated by the Harris-Benedict equation, or HBEE). The REE of patients in groups A and B declined after this period, whereas the long-term ventilated patients in the prognostically unfavorable group C showed a high REE up to the 45th day, usually accompanied by severe organ dysfunction and major metabolic disorders. During this time a nutritional regimen meeting the actual REE could not be achieved. In the clinical situation when indirect calorimetry is not available, REE can be stated to be 50% to 60% above HBEE in patients with >20% BSAB for at least 20 days. Expecting a stable clinical course in patients with a predicted mortality of <20% (group A), oral nutrition usually seems sufficient after a short period of artificial nutritional support (1 week). Patients with a predicted mortality of more than 20% have a complication-burdened clinical course and a prolonged period of ventilation (groups B and C). These patients need parenteral and enteral nutrition for at least 20 days after trauma to prevent severe malnutrition.

Accuracy of predictive methods to estimate resting energy expenditure of thermally‐injured patients

“…39,45 Days postthermal injury may also be an important influencing factor. 28,35,42,44 Our data are in agreement with others in that patients with thermal injury demonstrate a sustained hypermetabolic plateau which may persist for 20 days or longer postburn (Fig. 4).…”

“…The extent of thermal injury (%BSAB) has been suggested as a primary influencing factor by numerous investigators and, as a result, has been included in their predictive methods. 1,28,31,32,35,36,[38][39][40][41][42][43][44] The more recent publications suggest a maximum MEE of about twice that of basal. 3,35,36,38 Our data corroborate these findings as none of the patients exceeded hypermetabolism beyond 207% of predicted by the Harris Benedict equations.…”

Proteasome Inhibition After Burn Injury

“…Furthermore, the magnitude of the increase in REE that we observed in animals compares well with increases in REE that have been measured with indirect calorimetry in patients with similar burn sizes (33, 34). …”

Metabolic Flux Analysis of Postburn Hepatic Hypermetabolism

“…It is followed by a flow phase, where patients exhibit increased resting energy expenditure, hyperglycemia, and net proteolysis of myofibrillar protein in muscle. This hypermetabolic and hypercatabolic state can persist for several weeks and even months (Khorram-Sefat et al, 1999). While hypermetabolism is believed to be beneficial for the short term in that it mobilizes host resources in order to aid in wound healing, if persistent, it is associated with the development of cell and organ injury, progressive multiple organ dysfunction syndrome, and, eventually, death (Cerra, 1987(Cerra, , 1992.…”