Use of a non-contact radiant heat bandage on ischemic dermal infections in an ovine model

Background: Chronic non-healing foot wounds are common complication in the diabetic population. Local radiant heat bandage has recently been proposed as an effective adjuvant. The purpose of this study was to evaluate the efficacy of such bandage in controlling infection in an ovine ischemic wound model. Material/Methods: Bilateral flank ischemic wounds were created in a total of 42 sheep. 14 sheep were challenged with Pseudomonas aeruginosa (PA), 13 with Escherichia Coil (EC), and 15 with Methicillin resistant staphylococcus aureus (MRSA). The left flank was designated the treatment. side and the right the control side. The radiant heat bandage was applied for a total of 10 clays. The animal were then euthanized and the wounds harvested for bacterial quantification. Results: 39 sheep completed the study. Mean bacterial counts were has follows: for MRSA, control 7.6x10⁵ CFU/gm vs. heated 2.0x10⁵ CFU/gm (p=0.16); for EC, control 1.1x10⁶ CFU/gm vs. heated 2.7x10⁵ CFU/gm (p=0.006); PA, control 1.7x10⁶ CFU/gm vs. heated 3.9x10⁹ CFU/gm (p=0.001). Conclusion: Non-contact radiant bandages controls bacterial growth in ischemic wounds infected with MRSA or EC and may potentially improve wound healing. Wounds infected with PA should no be submitted to such treatment.