Topical application of cerium nitrate prevents burn edema after burn plasma transfer

Thermal injuries of more than 20% body surface area (BSA) result in systemic capillary leakage with subsequent edema. This can similarly be induced by burn plasma transfer (BPT) from burned individuals to healthy rats. We evaluated if cerium nitrate (CN) bathing can prevent edema after BPT. Therefore, donor rats (DR) underwent thermal injury (100 degrees C water, 30%BSA, 12 s) for positive controls and were additionally bathed in CN (0.05M, at 10 and 120 min) for study groups. For negative controls DR underwent shamburn (37 degrees C water, 30%BSA, 12 s). DR-plasma (harvested 4 h post trauma) was transferred to healthy individuals. Intravital microscopy was performed in mesenteric venules (0/60/120 min). Edema was assessed by FITC-albumin extravasation. Additionally, leukocyte sticking (cells/mm(2)) and micro hemodynamic parameters were assessed. Significant systemic capillary leakage was observed after BPT at 120 min. Edema formation was significantly lower in negative controls. Topical CN application after 10 and 120 min reduced FITC-efflux to baseline levels. Adherent leukocytes increased slightly in all groups. Leukocyte-sticking tended to be reduced after CN bathing. In conclusion, BPT induces burn edema in healthy individuals. CN bathing after 10 and 120 min reduces mediator levels in burned individuals. Therefore, BPT after CN application does not induce burn shock anymore. Burn edema is partially independent from leukocyte activation because CN significantly influences macromolecular leakage whereas leukocyte activation is not significantly altered.