Matthias Napp

Skin and wound decontamination of multidrug-resistant bacteria by cold atmospheric plasma coagulation

Novel concepts to limit the spread of multidrug‐resistant bacteria (MDR) are urgently needed. Since treatment with cold atmospheric plasma (CAP) has shown significant antibacterial properties, the purpose of this study was to evaluate the ability of CAP to eliminate MDR‐ compared to non‐MDR‐pathogens in chronic wounds.

Accidental circular saw hand injuries: trauma mechanisms, injury patterns, and accident insurance.

INTRODUCTION Hand injuries due to circular saws are a common reason for patients seeking medical care in emergency departments. With respect to cases of insurance fraud, these injuries are of medico-legal interest. It is the aim of this study to investigate the critical circumstances of the incidents, the accident mechanism, and the specific injury patterns of circular saw related hand injuries with regard to accident insurance coverage. PATIENTS AND METHODS Circular saw related hand injuries for the years 1999 through 2007 were followed-up and assessed in detail. Type, severity and pattern of the injury were assessed. An accident analysis investigated characteristic of the activities, of the saws, of the stock/cutting material, operational activities of the operators prior to/at the time of the incident, and detailed information on the insurance status. RESULTS The follow-up study encompassed 114 patients. A majority of these were covered by private or statutory accident insurances. Compensation payments were made in all cases. All lesions involved one hand, mainly the left non-dominant hand. Thumb and index were at highest risk for injury. One-finger injuries occurred mainly at the middle or distal phalanx. With increasing number of affected fingers, the level of the injury moved closer to the proximal phalanx. A majority of injuries occurred during do-it-yourself activities. Among blade contact injuries, the so-called kickback-mechanism was at highest risk. CONCLUSION Positive circumstantial indications of a self-inflicted injury, which are often cited in the literature are less conclusive for the medico-legal decision finding. The detailed anatomic description of any lesions and the alleged accident mechanism as initially described by the patients in the emergency setting is the basis for any later accident reconstruction.

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.

Distinct cytokine and chemokine patterns in chronic diabetic ulcers and acute wounds.

Wound healing is a central physiological process that restores the barrier properties of the skin after injury and infection.[1] Defective wound healing is a burden to millions of patients worldwide with diabetes mellitus being a major risk factor for chronic wounds.[2] Besides wound bed infections, especially neuropathy and angiopathy accompanied with decreased blood supply and excessive necrotic tissue are the major problems[3] resulting in a mislead inflammation that ultimately disturbs the sequence of events necessary for wound closure.[4] Inflammation is governed mainly by wound bed resident leucocytes and skin cells[5] as well as their intercellular communication which strongly depends on signalling molecules (cytokines and chemokines).[6] Nonhealing wounds were shown to display an imbalance in these molecular signatures.[7]

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.

Humane killers, human injury: functional outcome of vole captive bolt injuries.

BACKGROUND High-pressure blast injuries to the hand due to vole captive bolt devices are serious injuries that are to a great extent unknown to emergency care operators and trauma surgeons. There is no study on the functional outcome of these patients. METHODS We assessed the functional outcome of patients with injuries inflicted by vole captive bolt devices. Therefore, a protocol consisting of a physical examination and an assessment of static muscle power (grip and pinch strength) was performed. To capture the subjective experience of patients regarding their injury related disability and impairment, the DASH follow-up questionnaire was used. Based on clinical/radiologic findings and outcome, a classification of this unique subgroup of blast injuries was developed. RESULTS The functional outcome of 34 patients suffering hand injuries due to captive bolt devices between 2004 and 2007 was assessed. A significant reduction of static muscle testing parameters compared with the uninjured hand was revealed. Fourteen patients lost a digit. Average time lost from work was 5.4 weeks. CONCLUSION Vole captive bolt device-related hand injuries are followed by deterioration of hand function. The present observations alarmed national authorities. The manufacturers were required to take engineering and teaching measures to rule out handling errors that were identified as leading cause of injury.

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.

Aseptisches Operieren in Orthopädie und Unfallchirurgie

ZusammenfassungHintergrundPostoperative Wundinfektionen in Unfallchirurgie und Orthopädie sind in einer Ära von technischem Fortschritt und alternder Bevölkerung von besonderer Bedeutung, da sie meist einen komplizierten, langwierigen und teuren Heilungsverlauf verursachen. ErregerspektrumTypische Erreger sind Staphylococcus aureus, Biofilm produzierender Staphylococcus epidermidis, hämolysierende Streptokokken und die gramnegativen Stäbchen Escherichia coli und Pseudomonas aeruginosa. ProblematikKritische Punkte in der Infektiogenese sind präoperative Hautdesinfektion, Händehygiene, sichere chirurgische Technik, Barrieremaßnahmen zum Schutz vor Erregerverbreitung sowie ein funktionierendes Hygieneregime im Rahmen eines adäquaten Qualitätsmanagements. Die Basisinfektrate in Unfallchirurgie und Orthopädie ist im Vergleich zu anderen chirurgischen Disziplinen höher, nichtsdestotrotz kann durch Implementierung risikoadaptierter Präventionsmaßnahmen eine Verbesserung erzielt werden.AbstractBackgroundSurgical site infections (SSI) in traumatology and orthopedics in the era of increasing technical improvements and an aging and increasingly fragile population are of crucial importance mostly showing complicated, long-term and expensive outcome. Spectrum of pathogensTypical wound pathogens of these infections include Staphylococcus aureus, biofilm-producing Staphylococcus epidermidis, hemolytic Streptococci and the Gram-negative rods Escherichia coli and Pseudomonas aeruginosa. ProblemsCritical points in the development of SSI are preoperative skin antisepsis, hand hygiene, safe and skilled technique by surgeons, barrier nursing to prevent spread of pathogens, postoperative wound surveillance and a functioning hygiene regime in the context of an adequate quality management system. Baseline infection incidence in traumatology and orthopedics is inherently higher compared with other surgical disciplines; nevertheless, significant improvements can be achieved by the implementation of risk-adapted infection control measures.

Cold Atmospheric Plasma in the Treatment of Osteosarcoma

Human osteosarcoma (OS) is the most common primary malignant bone tumor occurring most commonly in adolescents and young adults. Major improvements in disease-free survival have been achieved by implementing a combination therapy consisting of radical surgical resection of the tumor and systemic multi-agent chemotherapy. However, long-term survival remains poor, so novel targeted therapies to improve outcomes for patients with osteosarcoma remains an area of active research. This includes immunotherapy, photodynamic therapy, or treatment with nanoparticles. Cold atmospheric plasma (CAP), a highly reactive (partially) ionized physical state, has been shown to inherit a significant anticancer capacity, leading to a new field in medicine called “plasma oncology.” The current article summarizes the potential of CAP in the treatment of human OS and reviews the underlying molecular mode of action.

Influence of preoperative skin sealing with cyanoacrylate on microbial contamination of surgical wounds following trauma surgery: a prospective, blinded, controlled observational study

OBJECTIVE Intraoperative bacterial contamination is a risk factor for surgical site infections (SSIs). This prospective, randomized, blinded, controlled trial (Reg. No. BB08/12) investigated the effect of a cyanoacrylate-based skin sealant (InteguSeal) on intraoperative wound contamination during trauma surgery. METHODS A total of 128 patients undergoing trauma surgery were assigned randomly to an intervention (n=62) or a control group (n=66). Surgical sites were investigated at three locations: maximum incision depth (base), wound margin prior to wound closure (margin), and the surgical sutures (suture). Colony-forming units (CFU) were counted after 48h of incubation. RESULTS Overall, significantly lower CFU counts were obtained for samples from the intervention group at all three sample sites compared to the control group. The difference, however, was only significant for the suture site (p=0.040). CONCLUSIONS Preoperative sealing reduced microbial contamination on sutures during surgery, while the overall wound contamination remained unchanged. Hence, prevention of the clinically more relevant deep SSIs may not be expected. However, this study was not designed to detect differences in the rate of SSI. The role of the reduction in suture contamination with regard to the prevention of SSI remains to be evaluated.