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Increased ambient temperatures during the care of severely burned patients are essential for mitigating hypothermia and minimizing the impact of consecutive hypermetabolism. For involved medical staff, those conditions may lead to impaired concentration, possibly negatively affecting optimal patient care. Yet, alleviation strategies are lacking. As a novel coping strategy, cooling wear may be an effective means. This explorative study aimed to investigate the effect of high ambient temperatures on the concentration capacity and cooling wear to alleviate thermal stress. The effects of high ambient temperatures and the additional use of cooling wear on the concentration capacity of medical staff were investigated in six subjects during two simulated burn surgeries. Each individual served as his/her own control undergoing one simulation with and one without cooling wear. Concentration capacity was measured before and after each simulation with a standardized test. The results suggested that high ambient temperatures, as used in burn medicine, negatively affect human concentration capacity. The initial assessment of concentration capacity yielded homogenous values. After heat exposure, subjects wearing cooling wear showed a higher concentration capacity and a lower error rate compared to subjects without cooling wear. Summing up, temperature-related decrements in vigilance and performance among medical personnel may impair the patients’ outcome. As an opportunity to withstand thermal stress and improve medical care and safety, cooling wear showed promising results and may be used as a heat alleviator. Burn medicine may particularly benefit from further development and rigorous investigation of cooling strategies.

Summary Background High temperatures at workplaces lead to health-related risks and premature exhaustion. The coronavirus disease 2019 (COVID-19) pandemic requires many health professionals to perform under unfavorable conditions. Personal protective equipment (PPE) causes thermal stress and negatively affects performance. Patients, materials and methods This pilot project investigated the effects of PPE and additional cooling wear on physiological parameters and concentration of six healthy staff members of the Plastic Surgery Department of the Medical University of Graz, Austria during simulated patient care. In this study two 1‑hour cycles with patient care-related tasks with PPE and PPE + cooling-wear, respectively, were conducted. A third cycle with scrubs exclusively served as baseline/negative control. The assessment occurred immediately pre-cycles and post-cycles. Results Pre-cycle assessments showed no significant differences between the cycles. After PPE cycle, increased physical stress levels and decrements in concentration capacity were observed. Physiological parameters were significantly less affected in the cooling cycle, while concentration capacity slightly increased. Conclusion COVID-19 PPE causes considerable thermal stress, ultimately affecting human performance. As opportunity to withstand thermal stress, and improve patients’ and professionals’ safety, cooling-wear can be considered relevant. Medical personnel performing in exceptional situations may particularly benefit from further development and investigation of cooling strategies.

Background Burn wound progression is a significant problem as burns initially thought to be superficial can actually become full thickness over time. Cooling is an efficient method to reduce burn wound conversion. However, if the cooling agent is below room temperature, depending on the wound size the patient is at risk of hypothermia. Additionally, tissue perfusion is reduced leading to an aggravation of burn wound progression. We investigated if wound dressings based on non-pre-cooled bacterial nanocellulose (BNC) with a high water content cool a burn just by evaporation and reduce the intradermal damages in the skin. Material and methods In a human ex-vivo model, skin explants underwent contact burns using a 100 °C hot steel block. The burned areas were divided into two groups of which one was cooled with a BNC-based wound dressing. Intradermal temperature probes measured temperature in cooled and uncooled burn sites over 24 h. For histological assessments of the burned areas biopsies were taken at different time points. High mobility group box-1 (HMBG1) staining served as marker for cell vitality and necrosis in the different skin layers. Results Intradermal temperature measurement showed that application of the BNC-based wound dressing reduced temperature significantly in burned skin. This cooling effect resulted in a maximum temperature difference of 6.4 ± 1.9 °C and a significant mean reduction of the area under the curve in the first hour after burn of 62% (p Conclusion Based on our results, BNC-based wound dressings cool a burn. Intradermal temperature as well as thermal damage of the tissue was reduced. The tested BNC-based wound dressing can be used without pre-cooling to cool a burn as well as to reduce the burn BNC-based wound progression through its evaporation cooling effect.

Background Bacterial nanocellulose (BNC) is considered a promising carrier for various substances and novel approaches using BNC in combination with antiseptics are well documented. However, the difference in the molecular weight of these molecules influences their uptake by and release from BNC. Analysing the diffusion of standard molecules with different weight, e.g. dextrans, offers the possibility to investigate the mobility of various molecules. We aimed to test the use of BNC regarding uptake and release of different standard molecules as well as two commercially available antiseptics for possible applications in future wound dressings. Material and methods Diffusion profiles, uptake and release of three FITC-dextran molecules differing in weight as well as octenidine (Octenisept®) and povidone-iodine (Betaisodona®)-based antiseptics were tested with BNC-based wound dressings. Furthermore, the antiseptic efficacy of BNC in combination with antiseptics against Staphylococcus aureus was tested. Results Uptake and release capacity for FITC-dextran molecules showed a molecular weight-dependent mobility from BNC into an agarose gel. The loading capacity of BNC was also inversely proportional to the molecular weight of the antiseptics. The release test for octenidine showed a sustained and prolonged delivery into a solid matrix, whereas povidone-iodine was released faster. Both antiseptic solutions combined with BNC showed a good dose-dependent efficacy against S. aureus. Conclusion Results obtained from the mobility of FITC-dextran molecules in the BNC matrix could open possible applications for the combination of BNC with other molecules for medical applications. Combination of both tested antiseptics with BNC showed to be an efficient approach to control bacterial infections.

Introduction Cooling of burn injuries is most important, not only to reduce pain but also to reduce the intradermal damage as well as the burn wound conversion. Studies have shown that cooling for about 20 to 30 minutes using only plain tap water at moderate temperature is most efficient resulting in least intradermal damage. However, many burn injuries reach the hospital without any pre-clinical cooling, possibly due to the lack of a cooling agent. After a pilot study, we investigated if a bacterial nanocellulose (BNC)-based wound dressing containing about 95% water can cool a burn injury and if so the effect suffices to reduce the damage in the skin. Methods Skin explants from human donors were burned with inflicted a contact burn injury, of which half were treated with a BNC-based wound dressing and a paraffin gauze dressing. Intradermal temperature sensors measured the temperature changes in the dermis over the course of 24 hours. Biopsies were taken for histological evaluation at different time points. Results The intradermal measurements show high temperature spikes at the moment of the burn injuries. After the application of a BNC-based wound dressing the intradermal skin temperature was significantly reduced. The area under the curve in the treated group was significantly less than the untreated. The histological assessment showed according results with less damage in the treated group in comparison to the untreated. Conclusions Bacterial nanocellulose-based wound dressings with high water content significantly lower the intradermal temperature after a contact burn and reduce the thermal damage inflicted to the skin. A secondary dressing that permits the water to evaporate slower additionally prolongs the cooling effect. The use of such a wound dressing could find use in a preclinical setting where other cooling options are not available. Applicability of Research to Practice The findings of this experiment should be tested in an in-vivo setting prior to clinical use to investigate the possibility of inducing hypothermia with this treatment.

Background With the increase of antimicrobial resistance in recent decades, other methods of preventing and fighting infections must be considered. Burn patients, whose wound areas are often extensive, are especially prone to wound infections. The loading of bacterial nanocellulose (BNC) with antiseptics has already been successfully performed but unfortunately, the described procedure is time-consuming and thus not applicable in a clinical emergency setting. Therefore, a clinically feasible approach was established. Material and methods Sheets of BNC-based wound dressings were placed into antiseptic solutions containing PHMB (Prontosan® and LAVANID® 2) and were left to soak for up to two hours. At different time points, samples were analysed for their concentration of PHMB and antiseptic efficacy. Results Within 30 min, clinically relevant concentrations of PHMB were achieved in the BNC-based wound dressing. The 30-min PHMB uptake for Prontosan® and LAVANID® 2 resulted in concentrations of 0.05% and 0.019%, respectively. Samples from the PHMB loaded dressing showed a dose dependent antiseptic efficacy for Staphylococcus aureus. Conclusion This experiment showed that the loading of BNC-based wound dressings with PHMB-containing antiseptics was achieved by a simple and quick procedure. According to studies a PHMB concentration of 0.001% can already inhibits all bacterial growth, indicating that the concentrations of PHMB in the BNC-based wound dressings after 30 min are higher than the minimal inhibitory concentration and the antiseptic efficacy after 120 min loading analysed by an standardized bacterial disk diffusion assay was shown to be comparable to the clinically used Suprasorb® X + PHMB wound dressing.

Introduction Bacterial nanocellulose (BNC) is a novel wound dressing that consists of nearly 95% water. This hydrophilicity allows this matrix to absorb and release aqueous substances. We investigated how well BNC can absorb antiseptic substances in order to create on demand antimicrobial wound dressings. Methods Sheets of BNC-based wound dressings were placed in four different antiseptic substances. Punch biopsies were taken at different time points and the concentrations of the antiseptic agent was measured. Two PHMB-containing solutions, one octenidine-containing and one povidone-iodine-containing solution were tested. In addition, the release of the substances from the punch biopsies was examined. To test the efficacy of these novel wound dressing, the antimicrobial activity of the BNC sheets loaded with the antiseptic solutions were tested against Staphylococcus aureus. Results All antiseptic solutions showed excellent uptake into the BNC as well as release. Especially the PHMB- and octenidine-containing solutions already showed high values after only 30 minutes. The overall achieved concentrations were all highly effective against Staphylococcus aureus and were all higher than the minimal bactericidal concentration against MRSA. Conclusions Antiseptic, water-based solutions are excellently absorbed in a very short time and are released steadily over a period of time dependant on the size of the molecules. All tested antiseptic solutions reached effective antibacterial concentrations making them all suitable for the making of antiseptic BNC-based wound dressings. However, when using a commercially available solution and not a solution containing only the active ingredient, it must be taken into consideration that all ingredients have an effect on the uptake of the active substance and thus influence the maximum uptake and release concentration. Applicability of Research to Practice The findings of this experiment are ready to be used in practice.

Introduction Many professional groups have to work in places with high temperatures; this includes, for example, doctors and nursing staff working at burn centres. Increased ambient temperature during the care of severely burned patients in the operating theatre and intensive care unit is used to mitigate the loss of thermoregulation, prevent hypothermia, and minimize the impact of hypermetabolism. However, experimental evidence indicates, that even relatively mild thermal stress may affect human performance. Novel cooling strategies have been invented for reducing thermal stress in people, who are occupationally exposed to high temperatures and have for instance already been tested in the military field. Here, the present study investigated the effects of cooling wear on the performance under high ambient temperatures. Methods Effects of cooling wear on concentration and performance of surgeons were investigated in 12 subjects during a simulated burn surgery. Subjects were divided into two groups, one group wearing cooling wear and one control group with normal scrubs. Directly before the exposure to high ambient temperatures, subjects of both groups underwent standardized tests for concentration, manual dexterity and measurements of physiological parameters. After a simulated burn surgery of 1 hour, subjects underwent the same analysing procedure again. Results Results proved that even relatively mild thermal stress affects performance whereby complex actions, that require high concentration, are primarily affected. Initial values of both groups showed approximately homogenous values. After heat exposure, however, subjects who received cooling wear showed higher results in tests for concentration and manual dexterity. Furthermore, the comparison of physical parameters indicates the ability of cooling wear to reduce thermal stress and its’ negative effects on the human organism. Conclusions Decrements in vigilance, performance and endurance are well-documented effects of thermal stress. As an opportunity to withstand thermal stress and therefore improve medical care, cooling wear showed good results in many aspects. Applicability of Research to Practice Based on these promising results cooling strategies may be used as an important tool in medical sectors in the future. Burn medicine may particularly profit from further development and rigorous investigation of cooling strategies.

Introduction Inflammation is part of the physiological phases of wound healing. It serves the purpose to attract different immune cells in order to clean the wound from pathogens and debris and create an ideal environment for fibroblasts and keratinocytes to differentiate, migrate and divide in order to close the wound. Pathological inflammation caused by many different factors is often the underlying cause of prolonged wound healing and unfavourable outcome in burn patients. We wanted to investigate what influence an induced hyper-inflammation on wound healing has in a controlled environment. Methods In a porcine wound model, pigs received full-thickness wounds on their backs where hyper-inflammation was induced by application of a chemotherapeutic for 6 days. Control wounds were left without induction. Wound were scored on a daily basis for 16 days in total and biopsies were taken for RNA analysis as well as histological assessment. Results The results showed a rise in inflammation of the wounds and the surrounding tissue due to the induction. The wounds healed slower, needing up to seven more days to completely heal. The results of the RNA analysis showed high values of pro-inflammatory cytokines after the induction in comparison to the baseline and control wounds. Histological assessment showed thick layers of necrosis, adipocyte as well as leucocyte infiltration in the hyper-inflamed wounds compared to completely healed control wounds with all layers of epidermis visible. Conclusions Hyper-inflammation, even just for a short period of time, can significantly prolong the time of wound healing. These findings underline the importance of preventing and treating wound infections of burn patients in order to support physiological wound healing as well as to avert complications such as infections with multi-resistant microbes that are associated with prolonged hospital stays. Applicability of Research to Practice The findings of these experiments cannot be directly applied to practice however, the influence of inflammation should kept in mind when treating burn patients.

Background Different research groups have identified microorganisms on breast implants by sonication with significant correlation to the rate of capsular contracture. This substantiated the hypothesis of an infectious etiology of capsular contracture. However, no clinical consequence has been drawn from these results yet. Aim of this study was to review sonication results from breast implants and to evaluate the current preoperative antibiotic regime for breast-implant surgery. Methods We compared breast implant sonication culture results from published reports and our own database. Current perioperative antibiotic recommendations were compared with the susceptibility profile of the found organisms. Results We found Coagulase-negative staphylococci and Propionibacteria to be the main group of microorganism found by sonication on explanted breast implants. Most guidelines recommend cephalosporins for preoperative antibiotical prophylaxis for breast-implant surgery. Conclusion There is a discrepancy between antibiotic activity of commonly used antibiotics for preoperative prophylaxis of surgical site infections, and microorganisms found by sonication on breast implants, suspected to trigger the formation of capsular contracture. A targeted antibiotic prophylaxis for breast implant surgery with glycopeptides (e.g. Vancomycin) should be considered for the prevention of capsular contracture.

The aim of the study was to analyze the antimicrobial susceptibility of Austrian clinical Klebsiella spp. and Enterobacter spp. isolates linked to patient-related data over a time period from 1998 to 2014. The main findings of this study were (i) a marked difference of antibiotic susceptibility rates between different infection sites for both Klebsiella spp. and Enterobacter spp., (ii) significantly greater percentages of resistant isolates among both Klebsiella spp. and Enterobacter spp. in male patients compared to female patients and (iii) significantly greater percentages of resistant isolates among both Klebsiella spp. and Enterobacter spp. from hospital-derived samples compared to samples from the community. In conclusion, our statistical data analysis clearly indicated a strong association of patient-related data and Klebsiella spp. and Enterobacter spp. susceptibility profiles.