348 The Role of Inflammation, Platelets, and Microparticles/Nanoparticles in Burn Wounds

Abstract Introduction In the US, the incidence of burn injury is > 2 million cases/year. A significant amount of burn related morbidity and mortality is due in part to immune dysfunction and wound healing complications which leads to increased risks of infection, coagulopathy, multi-organ failure, and sepsis. Methods We conducted a prospective observational study of burn patients (≥18y). Citrated samples were collected at patient presentation. Whole blood aggregation (WBAgg) studies were performed immediately. TEGs were ordered as clinically indicated. Additional samples were collected at days 3, 7, 10, 14, 21, and 28, processed immediately, and plasma was kept frozen at -80oC until analysis. Samples were studied for microRNA, cytokines/chemokines, coagulation factors, and microparticles (MPs) concentration and identity. Results 57 patients have been enrolled in this study. The majority of patients had burns caused by flame exposure. The mean (± SD) age of patients was 47±16 and 70% were male. The mean total body surface area (TBSA) burn was 9.7±9.5% (range 0.3-76.0%). Most patients had abnormal WBAgg in response to ADP, collagen, and arachidonic acid. This was very obvious even in patients with as little as 1% TBSA. Significant increase in platelet counts were detected over the 28 days follow up. Most TEG tracings were normal or had shortened R times indicating hypercoagulable state. Higher TBSA% were associated with increased MP concentrations. Decreased IL-1α and IL-7 and increased IL-10, MCP-1 and IL-1RA levels at presentation were also seen with higher TBSA% (p