Impact of Isolated Burns on Major Organs: A Large Animal Model Characterized

Severe burn results in systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction (MOD). Currently, large-animal models of burn-induced SIRS/MOD mostly use secondary insults resulting in a paucity of knowledge on the effect of burn alone on different organ systems. The objective of the current study was to develop and characterize a large animal model of burn-induced SIRS over the course of 2 weeks. Yorkshire swine (n = 16) were randomized to sham controls (n = 4) or 40% total body surface area contact burns (n = 6 at 2 and 14 days post-burn). Blood chemistry and complete blood count analyses were performed at baseline and post-burn days 1, 2, 3, 7, 10, and 14. Upon euthanasia, tissue samples were taken for histopathology. Burns were found to be full thickness and did not re-epithelialize. SIRS was evidenced by increased body temperature, respiration rate, pulse, and white blood cell count for the duration of the experiment. Both acute liver injury and acute kidney injury were induced as determined biochemically and histologically. Histology also revealed atelectasis of the lungs which was associated with increased myeloperoxidase activity. Intestinal structure as well as enterocyte homeostasis was also disrupted. All of these organ abnormalities recovered to varying degrees by 14 days post-burn. We report a unique reproducible large animal model of burn-induced SIRS that can be tailored to specific organ systems for investigation into potential immunomodulatory interventions that prevent organ failure or promote organ recovery after burn injury.