Control of the hypermetabolic response to burn injury using environmental factors

This study was performed to establish the relative efficiency of occlusive dressings and variable ambient temperature (group I) versus no dressings and variable ambient temperature (group II) versus no dressings and electromagnetic heaters (group III) for controlling the postburn hypermetabolic response. Fifteen burn patients and five normal controls (group IV) were studied when subjectively comfortable using partitional calorimetry, after which each patient was cold stressed by sequentially decreasing external energy support, and repeating calorimetry studies and serial plasma catecholamine assays. The percentage increase in heat production above predicted normal values was significantly increased for all groups when cold (C) versus neutral (N) (group I: [N] 24 +/- 24 versus [C] 49 +/- 25%; group II: [N] 46 +/- 35 versus [C] 74 +/- 47%; group III: [N] 21 +/- 20 versus [C] 78 +/- 25%; group IV: [N] -9 +/- 12 versus [C] 16 +/- 10%, p less than 0.05 all comparisons). Plasma catecholamine values did not increase significantly when patients were subjectively cold. These studies do not support the role of catecholamines as the primary mediator in the cause of the postburn hypermetabolic response. Using the patients' subjective comfort status as a guide for external energy support, it is possible to greatly reduce but not to eliminate the hypermetabolic response to burn injury.