Risk and clinical impact of bacterial resistance/susceptibility to silver-based wound dressings: a systematic review

Silver-Based Dressings for Surgical Site Infection Prevention: Evidence from Randomized Trials

BACKGROUND

Surgical site infections (SSIs) are a major cause of postoperative complications, increasing morbidity and healthcare costs. Silver-based dressings are commonly used due to their antimicrobial properties, but their effectiveness in reducing SSIs remains unclear.

AIM

This systematic review and meta-analysis aim to evaluate the efficacy of silver-based dressings compared to non-silver dressings in preventing SSIs in randomized controlled trials (RCTs) METHODS: A systematic search was conducted in PubMed, Cochrane Library, and Embase to identify RCTs comparing silver-based to non-silver dressings for SSI prevention. The study protocol was registered in PROSPERO (CRD42024592966). Meta-analysis using random-effects models calculated pooled risk ratios (RR) with 95% confidence intervals (CI). Heterogeneity was assessed with the I2 statistic, and publication bias evaluated through funnel plots and Egger's test.

RESULTS

12 RCTs with 2,928 participants were included in the meta-analysis. Silver-based dressings significantly reduced SSI risk by 40% compared to non-silver dressings (RR: 0.60, 95% CI: 0.41-0.89, p<0.05), with moderate heterogeneity (I2 = 53%) CONCLUSIONS: : Silver-based dressings significantly reduce the risk of SSIs; however, further high-quality RCTs are needed to confirm their benefits across different surgical contexts and patient populations.

Implementación de buenas prácticas clínicas: serie de casos de heridas de difícil cicatrización con tratamiento en extremidades inferiores

Introducción:

El estándar de manejo de heridas de difícil cicatrización basado en buenas prácticas clínicas incluye la identificación adecuada y el tratamiento de factores de riesgo que influyen en el mal pronóstico de cicatrización de las heridas en los pacientes, como carga microbiana en biopelículas, inflamación crónica y presencia de tejido desvitalizado y senescente.

Objetivo:

Describir el estándar de manejo implementado en un policlínico para tratar usuarios con heridas de difícil cicatrización en extremidades inferiores y evaluar los resultados clínicos de los protocolos utilizados.

Método:

Se identificaron y se analizaron los factores de riesgo presentes en los usuarios. Se utilizó una escala de valoración de pronóstico según la etiología de la úlcera y se valoró integralmente al paciente. Se determinó el objetivo terapéutico a través de la guía TIMERS y se definió el protocolo de tratamiento en el policlínico, que incluyó la limpieza terapéutica de la herida con ácido hipocloroso estabilizado pH 5.5, el uso de apósitos bactericidas-antibiopelícula y distintas estrategias de desbridamiento en heridas con signos de infección. Luego, se instauró un tratamiento local para la disminución de marcadores inflamatorios persistentes a través del uso de apósitos con octasulfato de sacarosa en las heridas sin signos de infección local, y se llevó a cabo un seguimiento de la evolución de las heridas.

Resultados:

Todos los pacientes con heridas de difícil cicatrización derivados al policlínico y tratados con el protocolo actualizado en buenas prácticas clínicas lograron la cicatrización de las heridas. Los tiempos reportados (90–120 días) fueron concordantes con protocolos homólogos reportados en la literatura, y resultaron menores en relación con un grupo de pacientes categorizados en la misma escala de clasificación de pronóstico y gravedad. No se observaron complicaciones durante el tratamiento. Se alcanzó la cicatrización en todos los casos.

Conclusión:

El abordaje sistemático y el uso de estrategias terapéuticas adecuadas pueden promover la cicatrización de heridas en extremidades inferiores, mejorar los resultados clínicos y la calidad de vida de los pacientes.

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

OBJECTIVE

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.

METHOD

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.

RESULTS

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.

CONCLUSION

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.

TLC-Ag dressings: a prospective, multicentre study on 728 patients with wounds at risk of or with local infection

OBJECTIVE

This study aimed to evaluate the management of an unselected cohort of patients with wounds at risk of or with clinical signs of local infection, treated with two antimicrobial contact layers impregnated with silver (TLC-Ag healing matrix), under real-life conditions during the COVID-19 pandemic.

METHOD

A large, prospective, multicentre, observational study with two TLC-Ag dressings (UrgoTul Ag/Silver and UrgoTul Ag Lite Border, Laboratoires Urgo, France) was conducted in Germany between May 2020 and May 2021. The main outcomes included a description of the treated patients and their wound management, the changes in wound infection and wound healing outcomes over a maximum period of four weeks of treatment, as well as the overall clinical assessment of the performance, local tolerance and acceptability of dressings.

RESULTS

A total of 728 patients with wounds of various aetiologies and wound infection status were treated with the evaluated dressings in 39 centres for a mean duration of 26±19 days, with an intermediate visit conducted in 712 (97.8%) patients after a mean period of 12±9 days. At the initial visit, it was established that the majority of patients (60.4%) had a wound infection, while the remaining cohort presented first clinical signs of a local wound infection (25.1%) or were at risk of wound infection (13.2%) (unclear status in 1.2%). Throughout the study period, all the parameters of wound infection continuously decreased, resulting at the final visit in a reduction by 78.9% of the prevalence of local wound infections and by 72.0% of the clinical signs of wound infection, the most rapidly diminished clinical sign being wound deterioration. Concurrently, in terms of the healing process, 92.1% of the wounds healed or improved, 3.2% remained unchanged and 1.7% worsened (data missing for 3.0%), and an improvement of the periwound skin was reported in 65.7% of the patients. Overall, the two dressings were 'very well accepted' by the majority of patients, with no uncomfortable feeling at wearing and no pain at dressing removal, and were assessed by the physicians as 'very useful' in the majority of the cases with a 'very good' efficacy in terms of antimicrobial activity and promotion of the wound healing process. Similar results were reported regardless of the wound type treated or of the TLC-Ag dressing evaluated.

CONCLUSION

These results are consistent with previous clinical evidence on TLC-Ag dressings. They support the good efficacy, good tolerability and usefulness of these antimicrobial dressings in the management of patients with wounds at risk or with clinical signs of local infection, in association with appropriate standard of care.

Clinical Study on the Efficacy of Silver Ion Dressing Combined with Prontosan Gel Dressing in the Treatment of Diabetic Foot Ulcers and the Effect on Serum Inflammatory Factors

Diabetic foot ulcers (DFUs) have a high disability rate and have a great impact on patients and society, and the search for effective and economical treatment options is a major clinical concern. In this study, 112 patients with DFU admitted to two hospitals from October 2018 to November 2020 were randomly divided into 56 cases each in the single group treated with Prontosan gel dressing and the joint group treated on silver ion dressing combined with Prontosan gel dressing. Both groups of patients were evaluated for efficacy after 30 days of treatment. The number of days for debridement, granulation tissue growth time, epithelial tissue formation time, and wound healing time were observed and recorded in both groups. The trauma area, visual analogue score (VAS), and levels of inflammatory factors such as vascular endothelial adhesion molecule-1 (VCAM-1), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and C-reactive protein (CRP) were recorded before and after treatment in both groups. The occurrence of adverse reactions such as edema, fever, infection, and rash during treatment was recorded in both groups for safety assessment. Comparison of the abovementioned data showed that the clinical efficacy of the joint group was significantly higher than that of the single group. The number of days to clear wounds, granulation tissue growth time, epithelial tissue formation time, and wound healing time were significantly lower in the joint group than in the single group. The trauma area, VAS score, VCAM-1, IL-6, TNF-α, and CRP levels decreased in both groups after treatment compared with the pretreatment levels, with the joint group being lower than the single group. The results also showed that the difference in the overall incidence of adverse reactions between the two groups was not statistically significant, and the incidence was low and transient. In addition to the usual treatment regimen of blood glucose control and improvement of microcirculation for patients with DFU, combined treatment with silver ionomer dressings and Prontosan gel dressings can promote ulcer healing and improve foot wound regression. It has a stronger antibacterial effect and can more effectively reduce the inflammatory response of the ulcerated surface with fewer adverse effects, making it an effective and safe method for the treatment of DFU, and has implications for promotion.

Therapeutic Index for Local Infections score validity: a retrospective European analysis

OBJECTIVE

A score to identify local wound infections was developed by a panel of experts from seven European countries. The Therapeutic Index for Local Infections (TILI) score was designed for health professionals who are not specialised in wound care. This study was carried out to test the validity of the TILI score in everyday practice.

METHOD

Content validity was analysed by means of evaluation by a panel of experts, individually and face-to-face, followed by a European multicentred, retrospective, observational study. Participating clinicians sent anonymised copies of completed TILI scores for patients with leg ulcers along with a photograph of the wound for analysis by two blinded reviewers. Concordance (Kappa index) and convergent criterion validity (sensitivity, specificity, accuracy, Youden's J Index and receiver operator characteristic (ROC) or area under the curve (AUC) curve) were calculated to construct validity and reliability.

RESULTS

A total of 307 patients with leg ulcers from seven institutions in five European countries were included in this retrospective analysis. It was shown that the diagnosis of local wound infection could be documented well with five of the six clinical criteria included in the TILI score. By summing up these facultative criteria in comparison with any direct criteria that may be present, there would have been an indication for local antiseptic wound therapy in 22% of patients examined.

CONCLUSIONS

The results show that the TILI score is concordant with the expert assessment of patients and with good diagnostic characteristics. Thus, the easy-to-use TILI score can now be used in the daily routine practice of health professionals to diagnose local wound infections.