Effectiveness of a hydrophobic dressing for microorganisms' colonization of vascular ulcers: Protocol for a randomized controlled trial (CUCO-UV Study)

Synthesis of Yttria Nanoparticle-Loaded Electrospun Nanofibers for Enhanced Antimicrobial Activity, Biofilm Inhibition, and Alleviation of Diabetic Wounds

Diabetes-related sores and ulcers are quite common around the world and can cause complicated disruptions to both patient compliance and socioeconomic structure. Diabetic wounds take longer to heal due to pathophysiological causes, persistent infections, and increasingly severe medical problems. Nanoparticles (NPs) derived from nanotechnology have drawn interest due to their revolutionary potential in understanding the biological milieu and offering therapeutic strategies for wound healing. In this regard, the potential of yttrium oxide nanoparticles (YNPs) has been studied extensively to understand their efficacy in diabetic wound healing. Yttrium oxide nanoparticles having size in the range of 2-10 nm were prepared and incorporated into nanofibrous mats consisting of polyurethane as the matrix polymer, and leaf extract of Azadirachta indica and clindamycin hydrochloride as additive conventional antidiabetic and antibacterial agents to form S3. Physicochemical characterization tests confirmed the formation of nanofibers having average diameters in the range of 320-470 nm, respectively. The study demonstrated that S3 shows an enhanced zone of inhibition against E. coli (29 mm), S. aureus (32 mm), and P. aeruginosa (30 mm). Moreover, the nanofibrous mats also prevented microbial penetration and biofilm formation, as observed from MTT, CV, and confocal microscopy images. In vivo wound healing study conducted on diabetic mice revealed that S3 exhibited high wound contraction after 9 days of treatment. Additionally, the fabricated mat lowered plasma glucose levels, hepatotoxicity, and oxidative stress biomarkers. Therefore, it can be concluded that YNP-loaded nanofibrous composite mats have a strong potential in alleviating diabetic wounds.

Effectiveness of an enhanced silver-containing dressing in hard-to-heal venous leg ulcers: a randomised controlled trial

OBJECTIVE

To assess the efficacy and safety of a carboxymethylcellulose dressing containing ionic silver, ethylenediaminetetraacetic acid and benzethonium chloride (CISEB) versus a dialkylcarbamoyl chloride-coated dressing (DACC) in hard-to-heal venous leg ulcers (VLUs).

METHOD

In a multinational, multicentre, randomised controlled trial, patients with hard-to-heal VLUs were randomised 1:1 to receive CISEB (n=100) or DACC (n=103) for up to four weeks. VLUs that were not healed by week 4 were managed with standard of care for up to 12 weeks or until healed (whichever was sooner). The primary endpoint was complete wound closure at week 12. Additional endpoints included time to complete wound closure and incidence of adverse events (AEs).

RESULTS

The trial cohort included 203 patients. CISEB achieved a higher rate of complete wound closure by week 12 compared to DACC (74.8% versus 55.6%, respectively; p<0.0031), and was associated with a 35% increased likelihood of healing (risk ratio, 1.35; 95% confidence interval: 1.10-1.65). Median time to complete wound closure was shorter in the CISEB arm (56 days) compared to the DACC arm (70 days; p<0.0272). A smaller proportion of patients experienced an AE with CISEB compared to DACC (5.0% versus 17.6%, respectively).

CONCLUSION

Management of hard-to-heal VLUs with CISEB was associated with improved healing outcomes compared to DACC, without additional safety concerns. CISEB is a gelling fibre dressing with antimicrobial, metal-chelating and surfactant components that may promote an optimal healing environment to address the challenge of hard-to-heal wounds.

Efficacy of Dialkylcarbamoylchloride (DACC)-Impregnated Dressings in Surgical Wound Management: A Review

Surgical site infections (SSIs) are a significant challenge in postoperative care, leading to increased morbidity, extended hospital stays, and elevated healthcare costs. Traditional antimicrobial dressings, such as those containing silver or iodine, have limitations, including cytotoxicity and the potential for antimicrobial resistance. Dialkylcarbamoyl chloride (DACC)-impregnated dressings offer a novel approach, employing a physical mechanism to bind and remove bacteria without the use of chemical agents, thereby reducing the risk of resistance. This review summarizes current evidence on the efficacy of DACC dressings in preventing SSIs and promoting wound healing. Findings from multiple studies indicate that DACC dressings reduce bacterial burden and SSI rates across various surgical procedures, including cesarean sections and vascular surgeries. Additionally, DACC dressings demonstrate potential in managing hard-to-heal wounds, such as diabetic foot ulcers, by reducing bacterial load and biofilm formation. Furthermore, they present advantages in antimicrobial stewardship and cost-effectiveness by minimizing the need for antibiotics and decreasing overall healthcare expenses. However, the current literature is limited by small sample sizes, methodological weaknesses, heterogeneity in study designs, and a lack of long-term data. Future research should focus on high-quality randomized controlled trials across diverse surgical populations, comprehensive cost-effectiveness analyses, and long-term outcomes to establish the full clinical impact of DACC dressings. With further validation, DACC-impregnated dressings could become a critical tool in sustainable postoperative wound care.

Investigation of Chitosan-Based Hydrogels and Polycaprolactone-Based Electrospun Fibers as Wound Dressing Materials Based on Mechanical, Physical, and Chemical Characterization

The aim of this project is to fabricate fiber mats and hydrogel materials that constitute the two main components of a wound dressing material. The contributions of boric acid (BA) and zinc oxide (ZnO) to the physical and mechanical properties of polycaprolactone (PCL) is investigated. These materials are chosen for their antimicrobial and antifungal effects. Additionally, since chitosan forms brittle hydrogels, it is reinforced with polyvinyl alcohol (PVA) to improve ductility and water uptake properties. For these purposes, PCL, BA, ZnO, PVA, and chitosan are used in different ratios to fabricate nanofiber mats and hydrogels. Mechanical, physical, and chemical characteristics are examined. The highest elastic modulus and tensile strength are obtained from samples with 6% BA and 10% ZnO concentrations. ZnO-decorated fibers exhibit a higher elastic modulus than those with BA, though BA-containing fibers exhibit greater elongation before breakage. All fibers exhibit hydrophobic properties, which help to prevent biofilm formation. In compression tests, CS12 demonstrates the highest strength. Increasing the PVA content enhances ductility, while a higher concentration of chitosan results in a denser structure. This outcome is confirmed by FTIR and swelling tests. These findings highlight the optimal combinations of nanofibrous mats and hydrogels, offering guidance for future wound dressing designs that balance mechanical strength, water absorption, and antimicrobial properties. By stacking these nanofibrous mats and hydrogels in different orders, it is expected to achieve a wound care material that is suitable for various applications. The authors encourage experimentation with different configurations of these nanofiber and hydrogel stackings to observe their mechanical behavior under real-life conditions in future studies.

Resveratrol-coated chitosan mats promote angiogenesis for enhanced wound healing in animal model

BACKGROUND

Growing incidences of chronic wounds recommend the development of optimal therapeutic wound dressings. Electrospun nanofibers have been considered to show potential wound healing properties when accompanied by other wound dressing materials. This study aimed to explore the potential role of Chitosan (CS) nanofibrous mats coated with resveratrol (RS) as an antioxidant and pro-angiogenic agent in rat models of skin wound healing.

METHODS

Electrospun chitosan/polyethylene oxide (PEO) nanofibers were prepared using electrospinning technology and coated by 0.05 and 0.1 mg.ml resveratrol named as (CS/RS 0.05) and (CS/RS 0.1), respectively. The scaffolds were characterized physiochemically such as in vitro release study, TGA, FTIR spectroscopy analysis, biodegradability, and human dermal fibroblast seeding assay. The scaffold was subsequently used in vivo as a skin substitute on a rat skin wound model.

RESULTS

In vitro tests revealed that all scaffolds promoted cell adhesion and proliferation. However, more cell viability was observed in CS/RS 0.1 scaffold. The biocompatibility of the scaffolds was validated by MTT assay, and the results did not show any toxic effects on human dermal fibroblasts. It was observed that RS-coated scaffolds had the ability to release RS in a controlled manner. In in vivo tests CS/RS 0.1 scaffold had the greatest impact on the healing process by improving the neodermis formation and modulated inflammation in wound granulation tissue. Histological analysis revealed enhanced vascular endothelial growth factor expression, epithelialization and increased depth of wound granulation tissue.

CONCLUSIONS

The RS-coated CS/PEO nanofibrous scaffold accelerates wound healing and may be useful as a dressing for cell transfer and clinical skin regeneration.

Aquacel Ag Advantage/Ag+ Extra and Cutimed Sorbact in the management of hard-to-heal wounds: a cohort study

OBJECTIVE

To compare Aquacel Ag Advantage/Ag+ Extra (Aquacel Ag+) (Convatec, UK) and Cutimed Sorbact (Sorbact) (Essity, US) dressings indicated for the treatment of patients with venous leg ulcers (VLUs), diabetes foot ulcers (DFUs) and pressure injuries (PIs) for clinical performance and outcomes using real-world evidence in Germany and the US.

METHOD

This study was a chart audit review of patients who used either Aquacel Ag+ or Sorbact dressings in the 24 months prior to October 2022. Healthcare providers with access to electronic medical records and charts were asked to capture data via patient record forms. The quantitative data were analysed.

RESULTS

Findings in Germany were comparable between Aquacel Ag+ and Sorbact with regards to wound description, management and treatment outcomes, including percent area reduction and wound closure. A difference was that a greater proportion of Sorbact patients required surgery (0% versus 11%; p=0.039). In the US, a greater proportion of wounds were worsening before dressing in the Aquacel Ag+ cohort (49% versus 34%; p=0.010). A multinomial logistic regression yielded the result that patients who received Aquacel Ag+ were 3.53 times more likely to have the wound completely healed (p=0.033).

CONCLUSION

Both Aquacel Ag+ and Sorbact dressings are widely used in Germany and the US for patients with VLUs, DFUs and PIs. Our study found two important differences: patients who used Aquacel Ag+ were less likely to need further surgery in Germany; and in the US, there were significantly higher odds that wounds would completely heal with Aquacel Ag+ dressings compared to Sorbact.

Biodegradable piezoelectric skin-wound scaffold

Electrical stimulation (ES) induces wound healing and skin regeneration. Combining ES with the tissue-engineering approach, which relies on biomaterials to construct a replacement tissue graft, could offer a self-stimulated scaffold to heal skin-wounds without using potentially toxic growth factors and exogenous cells. Unfortunately, current ES technologies are either ineffective (external stimulations) or unsafe (implanted electrical devices using toxic batteries). Hence, we propose a novel wound-healing strategy that integrates ES with tissue engineering techniques by utilizing a biodegradable self-charged piezoelectric PLLA (Poly (l-lactic acid)) nanofiber matrix. This unique, safe, and stable piezoelectric scaffold can be activated by an external ultrasound (US) to produce well-controlled surface-charges with different polarities, thus serving multiple functions to suppress bacterial growth (negative surface charge) and promote skin regeneration (positive surface charge) at the same time. We demonstrate that the scaffold activated by low intensity/low frequency US can facilitate the proliferation of fibroblast/epithelial cells, enhance expression of genes (collagen I, III, and fibronectin) typical for the wound healing process, and suppress the growth of S. aureus and P. aeruginosa bacteria in vitro simultaneously. This approach induces rapid skin regeneration in a critical-sized skin wound mouse model in vivo. The piezoelectric PLLA skin scaffold thus assumes the role of a multi-tasking, biodegradable, battery-free electrical stimulator which is important for skin-wound healing and bacterial infection prevention simultaneuosly.

A Novel Tool for a Challenging Disease: Stasis Leg Ulcers Assessed Using QFlow in Triggered Angiography Noncontrast Enhanced Magnetic Resonance Imaging

Imaging characteristics of stasis leg ulcers (SLUs) are not easily demonstrated through existing diagnostic tools. Early diagnosis and treatment are crucial. This pilot study was conducted to assess the quantitative flow (QFlow) in triggered angiography noncontrast enhanced (TRANCE) magnetic resonance imaging (MRI) to identify the hemodynamics of victims with stasis leg ulcers (SLUs). This study included 33 patients with SLUs and 14 healthy controls (HC). The 33 patients with SLUs were divided into a reflux (15 patients) and a nonreflux group (18 patients). QFlow was done in the reflux, the nonreflux, and the HC. The stroke volume (SV), forward flow volume (FFV), absolute flow volume (AFV), mean flow (MF), and mean velocity (MV) were higher in the reflux than in the HC group in most segments, namely the external iliac vein (EIV), popliteal vein (PV), and great saphenous vein (GSV) (SV, p = 0.008; FFV, p = 0.008; absolute stroke volume (ASV), p = 0.008; MF, p = 0.002; MV, p = 0.009). No differences in the QFlow patterns were found in the GSV segment between the nonreflux group and the HC. Excellent performance in discriminating SLU with superficial venous reflux was reported for SV in the EIV and the PV (area under the curve (AUC) = 0.851 and 0.872), FFV in the EIV and PV (AUC = 0.854 and 0.869), ASV in the EIV and PV (AUC = 0.848 and 0.881), and MF in the EIV and PV (AUC = 0.866 and 0.868). The cutoff levels of SV/FFV/ASV/MF in the EIV/FV/PV/GSV for discriminating the SLU with superficial venous reflux were identified (p < 0.005). In conclusion, SLUs present different QFlow patterns by different etiology. The QFlow parameters of all vessel segments were higher in the morbid limbs of the reflux group than HC. The GSV segment of the nonreflux group displayed a pattern like the HC.

Stasis Leg Ulcers: Venous System Revises by Triggered Angiography Non-Contrast-Enhanced Sequence Magnetic Resonance Imaging

Objectives: The distribution of venous pathology in stasis leg ulcers is unclear. The main reason for this uncertainty is the lack of objective diagnostic tools. To fill this gap, we assessed the effectiveness of triggered angiography non-contrast-enhanced (TRANCE)-magnetic resonance imaging (MRI) in determining the venous status of patients with stasis leg ulcers. Methods: This prospective observational study included the data of 23 patients with stasis leg ulcers who underwent TRANCE-MRI between April 2017 and May 2020; the data were retrospectively analyzed. TRANCE MRI utilizes differences in vascular signal intensity during the cardiac cycle for subsequent image subtraction, providing not only a venogram but also an arteriogram without the use of contrast agents or radiation. Results: TRANCE MRI revealed that the stasis leg ulcers of nine of the 23 patients could be attributed to valvular insufficiency and venous occlusion (including deep venous thrombosis [DVT], May–Thurner syndrome, and other external compression). Moreover, TRANCE MRI demonstrated no venous pathology in five patients (21.7%). We analyzed TRANCE MRI hemodynamic parameters, namely stroke volume, forward flow volume, backward flow volume, regurgitant fraction, absolute volume, mean flux, stroke distance, and mean velocity, in the external iliac vein, femoral vein, popliteal vein, and great saphenous vein (GSV) in three of the patients with valvular insufficiency and three of those with venous occlusion. We found that the mean velocity and stroke volume in the GSV was higher than that in the popliteal vein in all patients with venous valvular insufficiency. Conclusions: Stasis leg ulcers may have no underlying venous disease and could be confirmed by TRANCE-MRI. TRANCE MRI has good Interrater reliability between Duplex study in greater saphenous venous insufficiency. It also potentially surpasses existing diagnostic modalities in terms of distinguishable hemodynamic figures. Accordingly, TRANCE-MRI is a safe and useful tool for examining stasis leg ulcers and is extensively applied currently.

Effectiveness of a hydrophobic dressing for microorganisms' colonization of vascular ulcers: Protocol for a randomized controlled trial (CUCO-UV Study)

AIM

To determine the effectiveness of a hydrophobic dressing (Cutimed Sorbact® ) against a silver dressing (Aquacel® Ag Extra) in the level of colonization of chronic venous leg ulcers. The secondary endpoints are health-related quality of life, level of pain, and time to complete healing.

DESIGN

Open randomized controlled trial, with blinded endpoint.

METHODS

Patients with chronic venous leg ulcers with signs of critical colonization will be randomized in a concealed sequence using computer software to receive one of the alternative dressings. A total of 204 participants recruited in Primary Health Care and nursing homes will be necessary to assure statistical power. Measures will include sociodemographic variables, wound-related variables (area, exudate, and time to healing), level of pain, adverse effects, and health-related quality of life. Smear samples will be collected from the ulcers and will be subject to DNA-typing technique through polymerase chain reaction to obtain the level of colony-forming units. Measures will be collected at baseline, 4, 8, and 12 weeks.

DISCUSSION

Elevated levels of microorganisms prevent wound healing and favour its chronification. The main target when colonization is present is to reduce the bacterial load to levels that promote immune system mobilization. Hydrophobic dressings prevent the formation of biofilm in the wound by means of physical effect, so that the possibility of antimicrobial resistance is significantly reduced.

IMPACT

Current evidence about the effectiveness of dressings to minimize venous leg ulcers colonization is very limited. Previous studies have important methodological flaws. This study will permit to obtain the effectiveness of hydrophobic dressings against silver dressings with a robust design based on conditions of routine clinical practice in Primary Health Care and nursing homes.