Examination of Local and Systemic In Vivo Responses to Electrical Injury Using an Electrical Burn Delivery System.

摘要

Electrical injuries are devastating and are difficult to manage due to the complexity of the tissue damage and physiological impacts. A paucity of literature exists which describes models for electrical injury. To date, those models have been used primarily to demonstrate thermal and morphological effects at the points of contact. Creating a more representative model for human injury and further elucidating the physics and pathophysiology of this unique form of tissue injury could be helpful in designing stage-appropriate therapy and improving limb salvage. An electrical burn delivery system was developed to accurately and reliably deliver electrical current at varying exposure times. A series of Sprague-Dawley rats were anesthetized and subjected to injury with 1000 V of direct current at incremental exposure times (2-20 seconds). Whole blood and plasma were obtained immediately before shock, immediately postinjury, and then hourly for 3 hours. Laser Doppler images of tissue adjacent to the entrance and exit wounds were obtained at the outlined time points to provide information on tissue perfusion. The electrical exposure was nonlethal in all animals. The size and the depth of contact injury increased in proportion to the expousure times and were reproducible. Skin adjacent to injury (both entrance and exit sites) exhibited marked edema within 30 minutes. In adjacent skin of upper extremity wounds, mean perfusion units increased immediately postinjury and then gradually decreased in proportion to the severity of the injuries. In the lower extremity, this phenomenon was only observed for short contact times, while longer contact times had marked malperfusion throughout. In the plasma, interleukin-10 and vascular endothelial growth factor levels were found to be augmented by injury.