Wound Irrigation Solutions Research Articles

The efficacy of antimicrobial solutions against multispecies bacterial biofilm with or without negative pressure wound therapy in an in vitro wound model.

Biofilm is the major challenge in chronic wound management. Instilling a wound cleansing solution aids in wound bed cleaning and infectious pathogen elimination. Negative pressure wound therapy (NPWT) improves the wound-healing process. This study investigated the efficacy of two antimicrobials (Vashe Wound Cleanser and Prontosan Wound Irrigation Solution) against a multispecies bacterial biofilm with or without NPWT in an in vitro wound model. A mixed multispecies biofilm containing Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, and Acinetobacter baumannii was developed and verified by scanning electron microscopy and fluorescent in situ hybridization. The efficacy of Vashe and Prontosan against multispecies biofilm with or without NPWT was evaluated by colony-forming unit (cfu) of each species and total bacterial number, and visually confirmed by live/dead stain and confocal microscopy. Prontosan reduced biofilm cell numbers significantly: 6 instils over 24 h resulting in 3.86 ± 0.14 cfu log10 reduction without NPWT and 4.75 ± 0.13 cfu log10 reduction combined with NPWT (P < 0.01) and 12 instils over 48 h resulting in 5.24 ± 0.11 cfu log10 reduction without NPWT and biofilm eradication with NPWT (P < 0.001). NPWT alone or combined with Vashe failed to reduce multispecies biofilm numbers significantly over 24 or 48 h. Prontosan significantly reduced biofilm cell numbers, with better efficacy over 48 than 24 h, emphasizing the necessity for persistent and robust treatment. NPWT enhanced the effectiveness of Prontosan instillation. However, NPWT alone or combined with Vashe showed limited efficacy and difficulty when combating the multispecies biofilm in vitro.

Minocycline-rifampin-impregnated penile prosthesis surfaces retain antimicrobial activity following irrigation with 0.05% chlorhexidine gluconate and antibiotic solutions.

0.05% Chlorhexidine gluconate (CHG; Irrisept [IrriMax]) is a commercial wound irrigation solution approved by the Food and Drug Administration that has seen recent adoption in the field of prosthetic urology; however, no study has evaluated whether 0.05% CHG is compatible with the minocycline-rifampin-impregnated surface (InhibiZone) of the AMS 700 penile prosthesis (Boston Scientific). To evaluate whether 0.05% CHG alters the antibiotic efficacy of the minocycline-rifampin-impregnated penile prosthesis surface. Discs (8 mm) were taken by a punch biopsy (Sklar) from sterile penile prosthesis reservoirs whose surfaces had been impregnated with rifampin and minocycline. Discs (n = 10) were suspended in 0.05% CHG, vancomycin and gentamicin, or normal saline for 2minutes to simulate intraoperative irrigation. Discs were then rinsed in normal saline to remove any unbound solution and incubated with methicillin-sensitive Staphylococcus aureus for 48hours. Adherent surface bacteria were suspended by shaking in a 0.3% Tween 20 solution, serially diluted, plated onto 3M PetriFilms, and counted. Kirby-Bauer disc diffusion assays were conducted to generalize findings across various organisms. Outcomes included (1) bacterial adherence to the implant surface measured as bacterial counts (in colony-forming units per milliliter) and (2) bacterial growth reduction measured as zones of inhibitions (in millimeters). Incubation of implant surfaces in 0.05% CHG did not alter recovered bacterial counts as compared with normal saline and vancomycin/gentamycin. Similarly, within a single bacterial species, 0.05% CHG and vancomycin/gentamycin did not alter zone-of-inhibition measurements in Kirby-Bauer disc diffusion studies. This study demonstrates in vitro that 0.05% CHG may be used directly on the minocycline-rifampin-impregnated surface without altering the antibiotic efficacy of the coating. Strengths include that this is the first study to evaluate if 0.05% CHG affected the minocycline-rifampin-impregnated surface. Limitations include the use of in vitro studies, which serve as a proxy for in vivo practices and may not be entirely accurate or translatable in a clinical setting. 0.05% CHG does not alter the antimicrobial activity of the minocycline-rifampin-impregnated surface as compared with vancomycin/gentamycin and normal saline in vitro; however, its efficacy in clinical practice remains to be evaluated.

Assessment between antiseptic and normal saline for negative pressure wound therapy with instillation and dwell time in diabetic foot infections

Negative pressure wound therapy with instillation and dwell time (NPWTi-d) is increasingly used for a diverse range of wounds. Meanwhile, the topical wound irrigation solution consisting of polyhexamethylene biguanide and betaine (PHMB-B) has shown efficacy in managing wound infections. However, the effectiveness of this solution as a topical instillation solution for NPWTi-d in patients with diabetic foot infections (DFIs) has not been thoroughly studied. The objective of this retrospective study was to evaluate the impact of using PHMB-B as the instillation solution during NPWTi-d on reducing bioburden and improving clinical outcomes in patients with DFIs. Between January 2017 and December 2022, a series of patients with DFIs received treatment with NPWTi-d, using either PHMB-B or normal saline as the instillation solution. Data collected retrospectively included demographic information, baseline wound characteristics, and treatment outcomes. The study included 61 patients in the PHMB-B group and 73 patients in the normal saline group, all diagnosed with DFIs. In comparison to patients treated with normal saline, patients with PHMB-B exhibited no significant differences in terms of wound bed preparation time (P = 0.5034), length of hospital stay (P = 0.6783), NPWTi-d application times (P = 0.1458), duration of systematic antimicrobial administration (P = 0.3567), or overall cost of hospitalization (P = 0.6713). The findings of the study suggest that the use of either PHMB-B or normal saline as an instillation solution in NPWTi-d for DFIs shows promise and effectiveness, yet no clinical distinction was observed between the two solutions.

High-Intensity Blue Light (450-460 nm) Phototherapy for Pseudomonas aeruginosa-Infected Wounds.

Background: Nosocomial wound infection with Pseudomonas aeruginosa (PA) is a serious complication often responsible for septic mortality of burn patients. High-intensity antimicrobial blue light (aBL) treatment may represent an alternative therapy for PA infections. Methods: Antibacterial effects of an light-emitting diode (LED) array (450-460 nm; 300 mW/cm2; 15/30 min; 270/540J/cm2) against PA were determined by suspension assay, biofilm assay, and a human skin wound model and compared with 15-min topically applied 3% citric acid (CA) and wound irrigation solution (Prontosan®; PRT). Results: The aBL reduced the bacterial number (2.51-3.56 log10 CFU/mL), whereas PRT or CA treatment achieved a 4.64 or 6.60 log10 CFU/mL reduction in suspension assays. The aBL reduced biofilm formation by 60%-66%. PRT or CA treatment showed reductions by 25% or 13%. In this study, aBL reduced bacterial number in biofilms (1.30-1.64 log10 CFU), but to a lower extent than PRT (2.41 log10 CFU) or CA (2.48 log10 CFU). In the wound skin model, aBL (2.21-2.33 log10 CFU) showed a bacterial reduction of the same magnitude as PRT (2.26 log10 CFU) and CA (2.30 log10 CFU). Conclusions: The aBL showed a significant antibacterial efficacy against PA and biofilm formation in a short time. However, a clinical application of aBL in wound therapy requires effective active skin cooling and eye protection, which in turn may limit clinical implementation.

Safety and effectiveness of an antiseptic wound cleansing and irrigation solution containing polyhexamethylene biguanide.

There is currently a wide range of cleansing and irrigation solutions available for wounds, many of which contain antimicrobial agents. The aim of this study was to assess the safety of HydroClean Solution (HARTMANN, Germany), a polyhexamethylene biguanide (PHMB)-containing irrigation solution, in a standard cytotoxicity assay, and to assess its effect in a three-dimensional (3D) full-thickness model of human skin. A number of commercially available wound cleansing and irrigation solutions, including the PHMB-containing irrigation solution, were tested in a cytotoxicity assay using L929 mouse fibroblasts (ISO 10993-5:2009). The PHMB-containing irrigation solution was then assessed in an in vitro human keratinocyte-fibroblast 3D full-thickness wounded skin model to determine its effect on wound healing over six days. The effect of the PHMB-containing irrigation solution on tissue viability was measured using a lactate dehydrogenase (LDH) assay, and proinflammatory effects were measured using an interleukin-6 (IL-6) production assay. The PHMB-containing irrigation solution was shown to be equivalent to other commercially available cleansing and irrigation solutions when tested in the L929 fibroblast cytotoxicity assay. When assessed in the in vitro 3D human full-thickness wound healing model, the PHMB-containing irrigation solution treatment resulted in no difference in levels of LDH or IL-6 when compared with levels produced in control Dulbecco's phosphate-buffered saline cultures. There was, however, a pronounced tissue thickening of the skin model in the periwound region. The experimental data presented in this study support the conclusion that the PHMB-containing irrigation solution has a safety profile similar to other commercially available cleansing and irrigation solutions. Evidence also suggests that the PHMB-containing irrigation solution does not affect tissue viability or proinflammatory cytokine production, as evidenced by LDH levels or the production of IL-6 in a 3D human full-thickness wound healing model. The PHMB-containing irrigation solution stimulated new tissue growth in the periwound region of the skin model.

High-Intensity Blue Light (450-460 nm) Phototherapy for Pseudomonas aeruginosa-Infected Wounds.

Background: Nosocomial wound infection with Pseudomonas aeruginosa (PA) is a serious complication often responsible for the septic mortality of burn patients. Objective: High-intensity antimicrobial blue light (aBL) treatment may represent an alternative therapy for PA infections and will be investigated in this study. Methods: Antibacterial effects of a light-emitting diode array (450-460 nm; 300 mW/cm2; 15/30 min; 270/540 J/cm2) against PA were determined by suspension assay, biofilm assay, and a human skin wound model and compared with 15-min topically applied 3% citric acid (CA) and wound irrigation solution (Prontosan®; PRT). Results: aBL reduced the bacterial number [2.51-3.56 log10 colony-forming unit (CFU)/mL], whereas PRT or CA treatment achieved a 4.64 or 6.60 log10 CFU/mL reduction in suspension assays. aBL reduced biofilm formation by 60-66%. PRT or CA treatment showed reductions by 25% or 13%. Here, aBL reduced bacterial number in biofilms (1.30-1.64 log10 CFU), but to a lower extend than PRT (2.41 log10 CFU) or CA (2.48 log10 CFU). In the wound skin model, aBL (2.21-2.33 log10 CFU) showed a bacterial reduction of the same magnitude as PRT (2.26 log10 CFU) and CA (2.30 log10 CFU). Conclusions: aBL showed a significant antibacterial efficacy against PA and biofilm formation in a short time. However, a clinical application of aBL in wound therapy requires effective active skin cooling and eye protection, which in turn may limit clinical implementation.

Impact of Interfering Substances on the Bactericidal Efficacy of Different Commercially Available Hypochlorous Acid-Based Wound Irrigation Solutions Commonly Found in South-East Asia.

The high prevalence of chronic wounds is a growing concern. Recently, hypochlorous acid (HOCl)-based solutions were introduced as an alternative antimicrobial for wound cleansing. In this study, we assessed the in vitro bactericidal activities of seven commercially available wound irrigation products commonly found in South-East Asia. The evaluation was conducted using quantitative suspension method, EN 13727 in either low or high protein conditions. Under low protein conditions, four out of the five HOCl products achieved bactericidal activity (≥5 log10 reduction factor; RF) within 2-5 min, and only one product achieved 5 log10 RF at 15 s. None of the HOCl achieved 5 log10 RF under high protein, even after 30 min of exposure time. In contrast, protein interference on the antimicrobial activities of polyhexamethylene biguanide-based product is less pronounced (low protein: 60 s vs. high protein: 2 min to attain ≥5 log10 RF). Octenidine dihydrochloride is the only active not affected by protein interference achieving ≥5 log10 RF within 15 s in both low and high protein conditions. These findings warrant the need to screen antimicrobial wound care products, especially HOCl-based products, in high protein condition to better reflect the antimicrobial activities in wound care.

The Antimicrobial Efficacy of Topically Applied Mafenide Acetate, Citric Acid and Wound Irrigation Solutions Lavanox and Prontosan against Pseudomonas aeruginosa.

Since burn wound infections caused by Pseudomonas aeruginosa (PA) lead to major complications and sepsis, this study evaluates the antimicrobial efficacy of the wound irrigation solutions Prontosan (PRT), Lavanox (LAV), citric acid (CA) and mafenide acetate (MA) using microbiology assays and an ex vivo skin wound model. In suspension assays, all the solutions showed significant reductions in bacterial number (log10 reduction: CA 5.77; LAV 4.91; PRT 4.74; MA 1.23). The biofilm assay revealed that PRT and LAV reduced biofilm formation by ~25% after a 15 min treatment, while PRT was most effective after a 24 h treatment (~68%). The number of PA in biofilms measured directly after a 15 min treatment was reduced most effectively with CA and LAV (log10 reductions ~2.5), whereas after a 24 h treatment, all solutions achieved only 1.36-1.65 log10 reductions. In the skin wound model, PRT and LAV provided the highest bacterial reduction after a 15 min treatment (log10 reduction 1.8-1.9), while MA was more effective after a 22 h treatment (log10 reduction 3.6). The results demonstrated the antimicrobial efficacy of all solutions against PA. Further investigation is needed to explore the potential clinical applications of a combination or alternating use of these solutions for infection prophylaxis and treatment of wound infections caused by PA.

Intraoperative Wound Lavage System for Deep Neck Infection: A Retrospective Cohort Study.

Introduction Multiple solutions are currently used to cleanse a deep neck infection (DNI), and a variety of devices are available to deliver wound irrigation solutions. An essential difference between these devices is the pressure that the irrigation solution exerts over the wound tissue. Objective To compare low-pressure and high-pressure irrigation delivery systems for wound cleansing in DNI. Methods we designed a retrospective cohort study and reviewed the medical records of patients operated on due to DNI from June 2016 to December 2017 at our institution. One cohort included patients treated with an intraoperative irrigation method that exerts low pressure over the irrigated tissue, and the other cohort, to a system capable of generating higher pressure. The Pearson Chi-squared test was used to analyze the data. Results A total of 42 patients whose ages ranged from 16 months to 72 years were included. The low-pressure irrigation system was used in 18 patients, and the high-pressure system was used in 24 patients. No statistical differences were observed regarding the irrigation methods, the complexity of the DNI, and the overall outcomes. Conclusions The present is the first study in which low- and high-pressure systems for wound lavage were evaluated in the treatment of DNI. When comparing these methods, we did not find one to be superior to the other; however, the additional cost associated with the high-pressure devices may not justify their in head and neck procedures.

Safety of troclosene sodium solution in decontamination of wounds: A prospective clinical and laboratory study.

Debate persists regarding the safety of hypochlorite-containing solutions in the decontamination of infected wounds. In 2006, the Israeli Ministry of Health withdrew licensing approval for troclosene sodium as a wound irrigation solution. The aim of this prospective clinical and laboratory study was to investigate the safety of troclosene sodium solution for decontamination of infected wounds. Troclosene sodium solution was used to treat 30 patients with 35 infected skin wounds of various etiologies and body areas, over a treatment period of 8 days. Data were gathered according to a prospectively designed protocol including general findings, wound-specific observations on Day 1 and Day 8 and laboratory parameters on Day 1 and Day 8. Wound swabs and tissue biopsy for culture were taken on Day 1 and Day 8. Statistical analysis was executed. Tests were 2-sided and p values of <0.05 were considered statistically significant. Eighteen males and 12 females, with 35 infected skin wounds were enrolled. There were no adverse clinical events. No significant changes were observed in general clinical observations. Statistically significant improvements were observed in: pain (p < 0.0001); edema (p < 0.0001); area of wound covered by granulation tissue (p < 0.0001); exudate (p < 0.0001); and erythema (p = 0.002). Prior to treatment, bacteria were demonstrated on microscopy or on culture in 90% of wound samples. On Day 8, this frequency reduced to 40%. There were no abnormal laboratory tests. Serum sodium concentration increased significantly between Day 1 and Day 8, whilst serum concentration of urea and concentrations of thrombocytes, leucocytes and neutrophils showed statistically significant reductions, but all values remained within normal laboratory ranges throughout the study period. Troclosene sodium solution is clinically safe in the management of infected wounds. These findings were presented to the Israel Ministry of Health and as a result, troclosene sodium was re-approved and licensed for decontamination of infected wounds in Israel.

Novel Intra- Operative Wound Irrigation Solution to Manage Infection Prevention in Patients Undergoing Primary Joint Arthroplasty: Retrospective Review of a Case Series of 308 Patients

Introduction Periprosthetic joint infection (PJI) after total hip and total knee arthroplasty is a devastating complication that is known to be associated with costly, resource-intensive interventions that place a significant burden on the US healthcare system. Estimated average hospital costs to treat female patients with PJI after total knee arthroplasty (TKA) or total hip arthroplasty (THA) in 2018 was $27,307, and $32,956 respectively. While the average costs to treat male patients with PJI after TKA or THA was $27,097 and $33,090 respectively. One strategy aimed at preventing PJI after total joint arthroplasty is the use of an intra-operative wound irrigation with an antiseptic solution. This retrospective case review was conducted to assess the incidence of PJI after using a novel wound antiseptic irrigation solution in patients undergoing primary TKA and THA. Methods The CDC defines surgical site infections, (SSI) as infections that occur after the surgery. The infections are further categorized as superficial involving the skin, or deep tissue. These infections are then divided into; superficial incisional SSI, deep incisional SSI, and organ-space SSI. In a study by Kannan et al., SSIs are more commonly seen in patients with more comorbidities. A consecutive series of 308 high-risk patients undergoing primary TKA or THA between January 4, 2021 and August 30, 2021, in whom Prontosan® Wound Irrigation Solution (B. Braun Medical Inc./ Innovice LLC), containing 0.1% Betaine, a surfactant, and 0.1% Polyhexanide (PHMB) was added to the intra-operative procedure, were evaluated for its impact on the incidence of PJI. The CDC’s Surgical Care Improvement Project, (SCIP) guidelines are standard of care and followed with each surgical procedure. The CDC recommends using antimicrobial prophylaxis at a time before skin incision such that the antibiotic concentration reaches the minimum bactericidal concentration at the time of skin incision, Berríos-Torres SI, et al. All data were prospectively submitted to the American Joint Replacement Registry (AJRR) was retrospectively analyzed to measure the incidence of postoperative infection. Results Primary TJA was performed on 308 patients; of these 10 patients were bilateral TKA (205 TKA procedures and 113 THA procedures). The use of Prontosan® Wound Irrigation Solution was associated with zero (0%) incidence of postoperative infection in this population of patients during a 90-day episode of care, nor at any time postoperatively. CMS defines total joint arthroplasty codes as a major surgery, and encounters or procedures within 90 days of the initiating procedure are included in the 90-day episode of care. No patients were lost to follow-up. Conclusion There was no incidence of PJI uncovered in this retrospective analysis. Adding Prontosan® Wound Irrigation Solution to the intra-operative protocol, contributed to the absence of PJI in this population and potentially avoided 1.74 female and 1.34 male TKA as well as .95 female and .75 THA resulting in total hospital-avoided costs of $83,824 and $56,126, respectively totaling $139,950.

Effectiveness of a polyhexamethylene biguanide-containing wound cleansing solution using experimental biofilm models.

Antiseptics are widely used in wound management to prevent or treat wound infections, and have been shown to have antibiofilm efficacy. The objective of this study was to assess the effectiveness of a polyhexamethylene biguanide (PHMB)-containing wound cleansing and irrigation solution on model biofilm of pathogens known to cause wound infections compared with a number of other antimicrobial wound cleansing and irrigation solutions. Staphylococcus aureus and Pseudomonas aeruginosa single-species biofilms were cultured using microtitre plate and Centers for Disease Control and Prevention (CDC) biofilm reactor methods. Following a 24-hour incubation period, the biofilms were rinsed to remove planktonic microorganisms and then challenged with wound cleansing and irrigation solutions. Following incubation of the biofilms with a variety of concentrations of the test solutions (50%, 75% or 100%) for 20, 30, 40, 50 or 60 minutes, remaining viable organisms from the treated biofilms were quantified. The six antimicrobial wound cleansing and irrigation solutions used were all effective in eradicating Staphylococcus aureus biofilm bacteria in both test models. However, the results were more variable for the more tolerant Pseudomonas aeruginosa biofilm. Only one of the six solutions (sea salt and oxychlorite/NaOCl-containing solution) was able to eradicate Pseudomonas aeruginosa biofilm using the microtitre plate assay. Of the six solutions, three (a solution containing PHMB and poloxamer 188 surfactant, a solution containing hypochlorous acid (HOCl) and a solution containing NaOCl/HOCl) showed increasing levels of eradication of Pseudomonas aeruginosa biofilm microorganisms with increasing concentration and exposure time. Using the CDC biofilm reactor model, all six cleansing and irrigation solutions, except for the solution containing HOCl, were able to eradicate Pseudomonas aeruginosa biofilms such that no viable microorganisms were recovered. This study demonstrated that a PHMB-containing wound cleansing and irrigation solution was as effective as other antimicrobial wound irrigation solutions for antibiofilm efficacy. Together with the low toxicity, good safety profile and absence of any reported acquisition of bacterial resistance to PHMB, the antibiofilm effectiveness data support the alignment of this cleansing and irrigation solution with antimicrobial stewardship (AMS) strategies.

Can Cold Atmospheric Plasma Be Used for Infection Control in Burns? A Preclinical Evaluation.

Wound infection with Pseudomonas aeruginosa (PA) is a serious complication and is responsible for higher rates of mortality in burn patients. Because of the resistance of PA to many antibiotics and antiseptics, an effective treatment is difficult. As a possible alternative, cold atmospheric plasma (CAP) can be considered for treatment, as antibacterial effects are known from some types of CAP. Hence, we preclinically tested the CAP device PlasmaOne and found that CAP was effective against PA in various test systems. CAP induced an accumulation of nitrite, nitrate, and hydrogen peroxide, combined with a decrease in pH in agar and solutions, which could be responsible for the antibacterial effects. In an ex vivo contamination wound model using human skin, a reduction in microbial load of about 1 log10 level was observed after 5 min of CAP treatment as well as an inhibition of biofilm formation. However, the efficacy of CAP was significantly lower when compared with commonly used antibacterial wound irrigation solutions. Nevertheless, a clinical use of CAP in the treatment of burn wounds is conceivable on account of the potential resistance of PA to common wound irrigation solutions and the possible wound healing-promoting effects of CAP.

Common Wound Irrigation Solutions Produce Different Responses in Infected vs Sterile Host Tissue: Murine Air Pouch Infection Model.

Despite desirable microbicidal actions of irrigation solutions in surgical site infection treatment, several studies demonstrate potential cytotoxic effects. This study investigated tissue damage caused by irrigation solutions in the presence or absence of infection. Air pouches were created in 60 mice and evenly divided into 2 groups as infected with Staphylococcus aureus and control. Groups were then subdivided both by type of solution and by timing after irrigation. Solutions included control (0.9% saline), bacitracin (33 IU/ml), 0.2% sodium oxychlorosene, 0.05% chlorhexidine gluconate, and 0.013% benzalkonium chloride. Inflammation decreased in infected pouches compared to the sterile ones for all solutions except bacitracin on day 0 and for all on day 7. On day 0, infected pouches had increased necrosis with bacitracin (P= .006), chlorhexidine gluconate (P= .18), and benzalkonium chloride (P= .07); on day 7, there was decreased necrosis in infected pouches for all solutions (P < .05) except for sodium oxychlorosene (P= .18). Edema decreased in infected pouches on day 0 for all solutions. On day 7, infected pouches had decreased edema with 0.9% saline, bacitracin, and benzalkonium chloride (P < .05) and increased edema with chlorhexidine gluconate (P < .05) and sodium oxychlorosene (P= .069). Bacitracin allowed for more bacteria growth than sodium oxychlorosene (P= .024), chlorhexidine gluconate (P= .025), and benzalkonium chloride (P= .025). The presence of bacteria led to less immediate tissue inflammation and edema, while tissue necrosis varied over time. The current study may guide surgeons on which solution to use and whether to irrigate a possibly sterile wound or joint.

The antibacterial and antibiofilm activity of Granudacyn in vitro in a 3D collagen wound infection model.

It is widely agreed that infection and the formation of biofilms play a major role in increasing inflammation and delaying wound healing. The aim of this study was to evaluate, in vitro, the antimicrobial activity of the wound irrigation solution, Granudacyn (Mölnlycke Health Care AB, Sweden) against planktonic bacteria and mature biofilms of clinically relevant bacterial species. Quantitative evaluation of bacterial numbers and confocal and/or scanning electron microscopy were used to evaluate the wound irrigation solution's antimicrobial/antibiofilm activity in standard laboratory conditions as well as in a three-dimensional (3D) collagen wound infection model. The wound irrigation solution exhibited a rapid and strong antibacterial activity against both Gram-positive and Gram-negative strains isolated from infected wounds in planktonic form, with a reduction in bacterial number of >4 Logs after as little as one minute of treatment. The wound irrigation solution also exerted an evident activity against preformed biofilms of Pseudomonas aeruginosa and Staphylococcus aureus (>3 Log and >1 Log reduction in colony forming unit number, respectively, after 15 minutes of incubation). Although the wound irrigation solution was partially inhibited in the presence of simulated wound fluid, it maintained a marked antibiofilm activity in in vivo-like conditions (ie. in a 3D collagen wound infection model) with a strong killing and a mild debridement effect, which was superior to standard saline. The results obtained in this study suggest that although the wound irrigation solution used might be partially inhibited by wound exudate, it has the potential to effectively kill wound infecting planktonic as well as biofilm bacteria.

Modifications of bacterial cellulose in wound care.

Wound infection may occur in acute and chronic wounds, wounds resulting from surgery or traffic accidents, and burns. Regardless of the extent and cause of the wound, prompt treatment is essential in reducing the patient's pain and limiting the spread of contamination. Improper wound care and associated chronic diseases may hinder the therapeutic success. Bacterial cellulose (BC) is highly biocompatible and has no cytotoxic effect on cells engaged in wound healing, such as fibroblasts and keratinocytes. Its high hydration level guarantees the maintenance of a moist wound environment. High mechanical strength, flexibility and resistance to damage make BC a promising material for dressings. Unfortunately, it does not display an inhibitory effect on bacterial growth. Introducing antimicrobial agents into the structure of BC has been a subject of many studies. This paper aims to present the latest reports on the possibility of the absorption of bacteriostatic and bactericidal agents in BC, such as metal particles, essential oils, antibiotics, antiseptics, and wound irrigation solutions. Moreover, the modifications in BC culture and post-production treatments in order to improve its physical properties are discussed.

Antimicrobial activity of hemodialysis catheter lock solutions in relation to other compounds with antiseptic properties.

Proper protection of vascular access after haemodialysis is one of the key measures for the prevention of catheter-related infections. Various substances with bactericidal and anticoagulant properties are used to fill catheters, but due to the unsatisfactory clinical effects and occurrence of adverse reactions, the search for new substances is still ongoing. In the present paper, we compared the in vitro antimicrobial activity of solutions used for tunnelled catheter locking (taurolidine, trisodium citrate) and solutions of substances that could potentially be used for this purpose (sodium bicarbonate, polyhexanide-betaine). The studies have been conducted on bacteria that most commonly cause catheter-related infections. The values of both minimum inhibitory concentration and minimum biofilm eradication concentration of the substances were determined. The ability of the tested substances to eradicate biofilm from the dialysis catheter surface was also evaluated. The results showed that polyhexanide-betaine inhibited the growth of all microbes comparably to taurolidine, even after ≥ 32-fold dilution. The activity of trisodium citrate and sodium bicarbonate was significantly lower. Polyhexanide exhibited the highest activity in the eradication of bacterial biofilm on polystyrene plates. The biofilm formed on a polyurethane dialysis catheter was resistant to complete eradication by the test substances. Polyhexanide-betaine and taurolidine showed the highest activity. Inhibition of bacterial growth regardless of species was observed not only at the highest concentration of these compounds but also after dilution 32–128x (taurolidine) and 32–1024x (polyhexanide-betaine). Therefore, it can be assumed that taurolidine application as a locking solution prevents catheter colonization and systemic infection development. Taurolidine displays high antimicrobial efficacy against Gram-positive cocci as well as Gram-negative bacilli. On the contrary, the lowest antibacterial effect displayed product contained sodium bicarbonate. The inhibitions of bacterial growth were not satisfactory to consider it as a substance for colonization prevention. Polyhexanidine-betaine possessed potent inhibitory and biofilm eradication properties comparing to all tested products. PHMB is applied as a wound irrigation solution worldwide. However, based on our results, we assume that the PHMB is a promising substance for catheter locking solutions thanks to its safety and high antimicrobial properties.

Quality of life improvement in patients with hard-to-heal leg wounds treated with Prontosan wound irrigation solution and wound gel.

This study evaluated the impact of four weeks of treatment with Prontosan Wound Irrigation Solution and Prontosan Wound Gel (B. Braun Medical Inc., US) on adults with hard-to-heal leg wounds. Overall change (weeks 1-5) in the Global Quality of Life scale (GQOL), changes in body, psyche and everyday life (EDL) quality of life (QoL) subscores, and changes in wound appearance and size after treatment were assessed. In this prospective, open-label, single-arm, five-centre study, non-hospitalised patients with no more than two wounds below the knee were recruited into the study; wounds were ≥5cm2 and ≤50cm2 and present for ≥4 weeks. The investigator or a designee applied the wound solution and gel to the wounds at clinic visits, and patients/caregivers applied the wound solution and gel at home. Wound-QoL questionnaires were completed at the initial screening and at each week of treatment. Wound size and photographs were obtained at pre- and post-treatment during clinic visits. A total of 43 patients were enrolled in the study. Mean GQOL scores decreased by 1.11 (46.1%). Body, psyche and EDL decreased by 1.17 (60.0%), 1.26 (41.8%) and 1.00 (42.2%), respectively. Wounds also showed improvement in odour, appearance and size. Adverse events were mild in intensity and transient in nature. This study demonstrated marked improvement in the QoL of patients with hard-to-heal leg wounds below the knee during four weeks of treatment with the wound solution and gel. Wounds also showed improvement in odour, appearance and size, and the treatment solution and gel were well tolerated. B. Braun Medical Inc. funded the research and preparation of this article. AK, DV, CRC and WC are employees of B. Braun Medical Inc. AO and RS declare no conflict of interest.

Protocols for the Use of a Novel Biofilm-Disrupting Wound Irrigation Solution for Prevention of Surgical-Site Infections After Total Joint Arthroplasty

Surgical-site infections are potential complications of total joint arthroplasties. Many strategies, ranging from preoperative to postoperative, have been developed in an attempt to mitigate this morbidity. Biofilms have been implicated in difficulties of treatment. Therefore, antimicrobials have been increasingly used to combat these problems. In this report, we will summarize different protocols which utilize a new antimicrobial solution. Providing surgeons with an effective prevention option for these infections is crucial for positive outcomes and the continued advancement in the practice of total joint arthroplasty.

Comparative analysis of biofilm models to determine the efficacy of antimicrobials.

Biofilms are one of the greatest challenges in today's treatment of chronic wounds. While antimicrobials kill platonic bacteria within seconds, they are rarely able to harm biofilms. In order to identify effective substances for antibacterial therapy, cost-efficient, standardized and reproducible models that aim to mimic the clinical situation are required. In this study, two 3D biofilm models based on human plasma with immune cells (lhBIOM) or based on sheep blood (sbBIOM) containing S. aureus or P. aeruginosa, are compared with the human biofilm model hpBIOM regarding their microscopic structure (scanning electron microscopy; SEM) and their bacterial resistance to octenidine hydrochloride (OCT) and a sodium hypochlorite (NaOCl) wound-irrigation solution. The three analyzed biofilm models show little to no reaction to treatment with the hypochlorous solution while planktonic S. aureus and P. aeruginosa cells are reduced within minutes. After 48h, octenidine hydrochloride manages to erode the biofilm matrix and significantly reduce the bacterial load. The determined effects are qualitatively reflected by SEM. Our results show that both ethically acceptable human and sheep blood based biofilm models can be used as a standard for in vitro testing of new antimicrobial substances. Due to their composition, both fulfill the criteria of a reality-reflecting model and therefore should be used in the approval for new antimicrobial agents.