The repetitive use of non-thermal dielectric barrier discharge plasma boosts cutaneous microcirculatory effects
Background: Non-thermal atmospheric plasma has proven its benefits in sterilization, cauterization and even in cancer reduction. Furthermore, physical plasma generated by dielectric barrier discharge (DBD) promotes wound healing in vivo and angiogenesis in vitro. Moreover, cutaneous blood flow and oxygen saturation can be improved in human skin. These effects are mostly explained by reactive oxygen species (ROS), but electric fields, currents and ultraviolet radiation may also have an impact on cells in the treated area. Usually, single session application is used. The aim of this study was to evaluate the effects of the repetitive use of cold atmospheric plasma (rCAP) on cutaneous microcirculation. Hypothesis: The repetitive use of non-thermal atmospheric plasma boosts cutaneous microcirculation effects. Methods: Microcirculatory data was assessed at a defined skin area of the radial forearm of 20 healthy volunteers (17males, 3 females; mean age 39.1 ± 14.8 years; BMI 26.4 ± 4.6 kg/m2). Microcirculatory measurements were performed under standardized conditions using a combined laser Doppler and photospectrometry system. After baseline measurement, CAP was applied by a DBD plasma device for 90 s and cutaneous microcirculation was assessed for 10 min. Afterwards, a second session of CAP application was performed and microcirculation was measured for another 10 min. Then, the third application was made and another 20 min of microcirculatory parameters were assessed. Results: Tissue oxygen saturation and postcapillary venous filling pressure significantly increased after the first application and returned to baseline values within 10 min after treatment. After the second and third applications, both parameters increased significantly vs. baseline until the end of the 40-minute measuring period. Cutaneous blood flow was significantly enhanced for 1 min after the first application, with no significant differences found during the remainder of the observation period. The second application improved and prolonged the effect significantly until 7 min and the third application until 13 min. Conclusion: Zhese data indicate that the repetitive use of non-thermal atmospheric plasma boosts and prolongs cutaneous microcirculation and might therefore be a potential tool to promote wound healing.