Metabolic Changes Following Major Burn Injury: How to Improve Outcome

The changes in patient metabolism following a major burn may be seen for more than 12 months after the initial injury. The ensuing period of hypermetabolism and catabolism post-burn leads to impaired immune function, decreased wound healing, erosion of lean body mass, and hinders rehabilitative efforts delaying reintegration into normal society. The typical changes in metabolism are the development of a hyperdynamic circulation [1], increased body temperature [2], increased protein catabolism with peripheral protein wasting [3], increased lipolysis leading to fatty infiltration of the liver [4], increased glycolysis and futile substrate cycling 5. These changes are responsible for much of the morbidity and mortality seen with such an injury and as such are important targets for available treatments including: early excision and grafting; aggressive treatment of sepsis, early commencement of high protein, high carbohydrate enteral feeding, elevation of the immediate environmental temperature to 31.5°C (±0.7°C); and early institution of an aerobic resistive exercise program. Several pharmacotherapeutic options are also available to further reduce erosion of lean body mass; these include anabolic agents such as recombinant human growth hormone, insulin, oxandrolone and beta-blockade with propranolol. This chapter will discuss the metabolic changes seen following a major burn and how different treatment options affect outcome.