Hermann Haase

Skin decontamination by low-temperature atmospheric pressure plasma jet and dielectric barrier discharge plasma

BACKGROUND Over the past few years, plasma medicine has become an important field in medical science. Cold plasma has proven anti-inflammatory, antimicrobial and antineoplastic effects. AIM To test the decontamination power of two cold plasma sources [low-temperature atmospheric pressure plasma jet (APPJ) and dielectric barrier discharge plasma (DBD)] in vivo on human fingertips. METHODS After 3, 15, 30, 60, 90, 120, 150, 180, 210 and 240 s of spot treatment with the APPJ and DBD, the log reduction factors (RFs) of physiological (PF) and artificially (AF) contaminated flora (Staphylococcus epidermidis and Micrococcus luteus) were calculated. The bacterial load was determined after counting. Tolerance (paresthesia, pain and heat) was measured using a numerical rating scale. FINDINGS Both plasma devices led to a significant reduction in PF and AF. The maximum log reduction factors for PF were 1.3 for the DBD at 210 s and 0.8 for the APPJ at 60 s. For AF, the maximum log reduction factors were 1.7 for the DBD at 90 s and 1.4 for the APPJ at 120 s. Treatment with both devices was well tolerated. CONCLUSION Both the APPJ and DBD were highly effective in eradicating PF and AF from the fingertips of healthy volunteers. No plasma-resistant isolates were observed. Cold plasma appears to have potential for skin disinfection. For hand hygiene purposes, plasma exposure times would need to be reduced significantly by technical means.

Cold plasma is well‐tolerated and does not disturb skin barrier or reduce skin moisture

Background: Cold plasma, a new treatment principle in dermatology based on ionic discharge delivering reactive molecular species and UV‐light, exhibits strong antimicrobial efficacy in vitro and in vivo. Before implementing plasma as new medical treatment tool, its safety must be proven, as well as assessing skin tolerance and patient acceptance.

Comparison between cold plasma, electrochemotherapy and combined therapy in a melanoma mouse model.

The study was undertaken to compare antitumor efficacy of electrochemotherapy (ECT) with cold plasma therapy (CP) in a melanoma mouse model. After melanoma implantation into the flank of C57BL/6N mice, CP by two different plasma sources (APPJ and DBD) was applied directly to the tumor surface. ECT was performed with bleomycin intravenously at a field strength of 1000 V/cm without or combined with CP. Primary endpoints were tumor growth acceleration (TGA), daily volume progression (DVP) and survival after treatment. Both plasma sources as single treatment showed a significant TGA delay, which proved less effective than ECT. CP (APPJ) combined with ECT (ECJ) significantly improved per cent mouse survival, with significant superiority compared with ECT. Plasma therapy alone albeit less effective seems a potential alternative to ECT in patients with melanoma and can be applied manifold in a session without general anaesthesia. Accordingly, CP alone and combined with ECT may serve as new option in palliative skin melanoma therapy.

Cutaneous vasomotion in patients with chronic venous insufficiency and the influence of compression therapy

We investigated in patients with chronic venous insufficiency (CVI) and after compression therapy the fluxmotion within characteristic frequency bands, which were described earlier by Bracic and Stefanovska (Bull. Math. Biol. 60 (1998), 919-935).Therefore, the frequency spectra of laser Doppler flux data of the 36 patients legs were compared with 41 legs of healthy subjects. In addition, 14 patients with CVI wore a compression stocking (interface pressure: 25-32 mmHg) or compression bandages and were measured after 4 weeks therapy. Data were analyzed by means of a Wavelet packet transformation (a combination of the Daubechies filter of order 4 and the Haar filter).We found significant differences between the patients and the healthy subjects in the frequency intervals of myogenic 0.06-0.16 Hz, respiratory 0.16-0.6 Hz and heart activity 0.6-1.6 Hz (p<0.05, Mann-Whitney U test). Furthermore, the main energy peak height in these frequency intervals increased with the severity of venous disease and was highest in patients with venous leg ulceration. Compression therapy had a significant influence in myogenic vessel activity, which has been proved by a positive frequency shift of 20% (p=0.007, one-sided by the exact Wilcoxon test).In venous disease fluxmotion was increased. Compression therapy over a period of 4 weeks improved myogenic vessel activity.

In vitro susceptibility of methicillin-resistant and methicillin-susceptible strains of Staphylococcus aureus to two different cold atmospheric plasma sources

BackgroundStaphylococcus aureus may be the most important wound pathogen and causative for most of surgical site infections. As many anti-staphylococcal drugs are useless because of resistance, novel antimicrobial strategies are strongly needed and may be provided by cold atmospheric plasma (CP), which is being currently investigated for antiseptic efficacy.MethodsTo test the antimicrobial properties of CP against Staphylococcus aureus, 168 methicillin-susceptible isolates (MSSA) and 50 methicillin-resistant isolates (MRSA) were treated with two technically different plasma sources [an atmospheric pressure plasma jet (APPJ) and a dielectric barrier discharge plasma (DBD)] in vitro.ResultsCP treatment allowed a reproducible and significant growth reduction of MRSA and MSSA. However, MRSA was significantly less susceptible to treatment with DBD than was MSSA, while no difference between MRSA and MSSA was found using APPJ.ConclusionsAs the initial physical antiseptic on skin, CP may be suitable for rapid decolonization of microbial pathogens in vivo. Each device must undergo validated efficacy testing prior to clinical application, as device related differences may occur.

Repetitive Immunoadsorption Cycles for Treatment of Severe Atopic Dermatitis

The purpose of the study was to investigate the clinical efficacy of repetitive IgE immunoadsorption (IA) cycles in severe atopic dermatitis (AD) with high serum IgE levels. A total of seven patients with severe AD with a history of no significant or longterm Scoring Atopic Dermatitis (SCORAD) reduction and total serum IgE levels >700 IU/mL were enrolled. The patients received one to five series of IA (Ig‐Therasorb adsorber columns; Miltenyi Biotec, Teterow, Germany) each consisting of five consecutive treatments which were performed on a monthly regimen. Overall, one patient received one, two patients two, one patient three, two patients four and one patient five cycles of IA. IA was well tolerated in all the studied AD patients and led to a significant decrease of SCORAD and IgE levels during each IA cycle in all the patients. The relative decrease of SCORAD and serum IgE levels after treatment was 11.1% and 80%, respectively, after five immunoadsorption series, 24.1% and 83.6%, respectively, after four series, 37.6% and 75.9%, respectively, after three series, 27.9% and 74.2%, respectively, after two series, and 25.1% and 74.8% after the 1st IA cycle. One of the patients exhibited a long lasting clinical benefit over more than 12 months after the 5th IA cycle. Repetitive IA with more than two cycles at intervals of 4 weeks induces a profound and persisting IgE reduction which is remarkable clinical efficacy improving SCORAD in severe AD with high serum IgE levels.

Compression therapy of leg ulcers with PAOD.

Objectives: To assess the clinical safety of a new short-stretch 2-layer compression system (3Mtm Cobantm 2 Lite) in patients with peripheral arterial occlusive disease (PAOD). This system combines a low resting pressure with a high working pressure. Methods: A pilot study was performed in 15 subjects with moderate PAOD, i.e. an ABPI of 0.5-0.8. Co-existing chronic venous insufficiency or leg ulcer was not mandatory. All subjects received the compression system which was reapplied at each study visit (days 1, 2, 3, 4, 7, 10, 14). The safety parameters were: sub-bandage pressure immediately after application, pressure-related skin damage, hypoxia-related pain, and adverse events. A product comfort questionnaire was completed at the last visit. Results: The average sub-bandage pressure of 30 mmHg defined by the protocol was achieved. No pressure-related skin damage or hypoxia-related pain was found. The reported adverse device effects were as expected for compression therapies, including dry skin and pruritus. The product comfort questionnaire completed by the subjects showed a good tolerability profile. Conclusion: The short-stretch 2-layer compression system (3Mtm Cobantm 2 Lite) was safe and well tolerated in subjects with moderate PAOD.

Antimicrobial Efficacy of a Historical High-Frequency Plasma Apparatus in Comparison With 2 Modern, Cold Atmospheric Pressure Plasma Devices.

Background. Today, highly sophisticated devices deliver cold atmospheric pressure plasma (CAPP) with a multitude of bioactive properties, opening the window to a new medical field: plasma medicine. Different techniques to create the optimal plasma device for different medical indications are currently being explored. However, even a 100 years ago, CAPP was briefly used in the related form of high-frequency therapy. The objective of our study was to compare historic with modern techniques regarding antimicrobial efficacy. Methods. First, 26 different clinical isolates of relevant wound pathogens were treated in vitro with a historic violet wand (VW) and 2 modern plasma sources (kINPen 09 and dielectric barrier discharge [DBD]) and the obtained inhibition areas (IAs) were compared. Second, a biofilm model was used to compare biofilm inactivation by VW, DBD, ethanol, and polyhexanide treatment. Results. DBD with the largest electrode produced the largest IAs. VW showed results similar to 2 different modes of the kINPen 09. IAs of VW were enlargeable by attaching a larger electrode. Against biofilms, VW was less effective than DBD but more effective than ethanol 70% and polyhexanide. Conclusion. The proven antimicrobial efficacy of VW may encourage the development of new, potent plasma devices based on the very simple and inexpensive technique of the historic high-frequency apparatus.

Hygienic safety of a new hydrodynamic wound debridement system.

BACKGROUND Unprotected hydrodynamic debridement can produce aerosols, with the risk of cross‐contamination and infection for patients and medical staff. OBJECTIVE To evaluate the hygienic safety and the role of aerosol prevention of a pulsatile debridement. METHODS & MATERIALS Bacterial emissions during debridement of chronic ulcer wounds of seven patients using the Debri‐Jet hydrodynamic in different modifications were analyzed. RESULTS Only a special aerosol prevention system (vacuum sensor, flexible cuff applicator) was able to effectively avoid the emission of infection relevant pathogens. The emitted pathogenic spectrum reflects the wound colonization of the individual patient wound; the most mobilized and emitted species were Staphylococcus aureus and Pseudomonas aeruginosa. CONCLUSION Unprotected pulsatile debridement can produce highly relevant bacterial emissions. Equipped with an elaborate aerosol prevention technique, the Debri‐Jet is a hygienically safe and effective debridement system and poses no more hygienic risks than conventional debridement. Because even conventional nonhydrodynamic debridement can produce cross‐contamination, basic hygienic precautions, including the wearing of masks, gloves, and eye‐shield, and performance of the procedure by trained staff must be used during debridement. This work was supported in part by financial support from Human Med Aktiengesellschaft, D‐19061 Schwerin without any influence over the scientific results of the investigation. Human Med, Schwerin, loaned the Debri‐Jet system.

Risk factors for MRSA colonization in dermatologic patients in Germany.

Detection of methicillin‐resistant Staphylococcus aureus (MRSA) carriage requires well‐defined risk factors (RFs). Except for “chronic wounds”, RFs are mostly specified in national recommendations. To avoid ineffective and expensive screening, we divided the entity “wounds” into different categories and calculated further RFs in dermatologic patients.