Metabolic changes following thermal injury.

Abstract

AbstractPatients with extensive thermal injuries have a tremendous, long‐lasting increase in transcutaneous heat loss by increased evaporation, radiation, and convection. Their ability to regulate skin temperature and heat loss is limited, and the core‐skin insulation is inadequate. The corresponding posttraumatic metabolic response is a massive catabolic drive revealed as insulin insufficiency and increased release of catecholamines and glucagon. This stimulates lipolysis, proteolysis, substrate flow to the liver, and gluconeogenesis of amino acids. The increased heat production is related to an endogenous reset in metabolic activity and is further influenced by environmental conditions. Extensively burned patients cannot overcome the cold stress to which they are exposed by an increased functional heat insulation or by tolerating decreasing body temperature without reacting with a costly increase in heat production and without shivering. If the burn patients are permitted to control the heat supply from infrared heaters until they feel comfortable and all kinds of external environmental disturbances are eliminated, it is possible to reduce their metabolic rate to the normal value for the actual core temperature. The daily caloric requirements can be estimated and, in patients receiving a combined parenteral‐enteral dietary program and infrared heat, weight loss can be entirely avoided. Infrared radiation is a practical and inexpensive way of distributing energy from the environment to the patient, suitable also in disaster situations. The ambient air temperature can be kept comfortable with respect to the patient's airways and to the nursing staff.