Continuous Microwave Enhances the Healing Process of Septic and Aseptic Wounds in Rabbits

Abstract

Evidence indicates that local application of continuous microwave (CM) has positive effects, for instance, on skin grafts and white blood cells. To investigate the role of CM on local wound healing under different conditions (septic and aseptic), a study was performed in an animal model. Seventy-two rabbits were randomly assigned to four groups of 18 each: group 1 and group 2 consisted of animals with aseptic wounds, and group 3 and group 4 consisted of animals with infected wounds. In the medial third of the dorsolateral body of each animal a wound was prepared under local anesthesia. Animals of groups 1 and 3 received CM treatment, and those of groups 2 and 4 served as controls. The treatment consisted of an irradiation with CM (fixed frequency 37 GHz, power flow density 1 mW/cm2) for 30 min once per day for 5 (group 1) or 7 days (group 3). No other conservative or surgical methods were applied. Aseptic wounds were covered with a sterile dressing. Infected wounds of controls (group 4) were irrigated with 10% NaCl once a day. Measurements were visual analysis, planimetric, bacterial, and immunological tests. The wound surface of treated animals with aseptic wounds became dry and plicated faster, the daily decrease of the wound surface area being more than twice as large as that in the control group (group 2, P < 0.05). Complete epithelization and adhesion of wounds appeared around Day 19 (95% Cl, 18.3 to 20.1) in group 3 and around Day 31 (95% Cl, 29.5 to 32.7) in group 4. The daily decrease of wound surface area was 6.3% in group 3 and 2.7% in group 4 (P < 0.05). Clear evidence of a stimulation of the immune system was observed. It is concluded that CM enhances the healing process of septic and aseptic wounds and stimulates the immune system.