Silver-containing dressing for surgical site infection in clean and clean-contaminated operations: a systematic review and meta-analysis of randomized controlled trials

[Silver Ion Decreases Foreign Body Reaction and Venous Neointimal Hyperplasia through the Inhibition of Interleukin-33 Expression]

INTRODUCTION

Vascular prosthetic grafts are widely used in vascular surgery; however, graft infection remains a major concern. Silver-coated vascular grafts have demonstrated anti-infection properties in clinical settings; however, whether the silver irons influence foreign body reaction or neointimal hyperplasia remains unclear.

METHODS

Sodium alginate and hyaluronic acid (SA/HA) hydrogel patches loaded with rhodamine, with or without silver, were fabricated. Patches were implanted in the subcutaneous or abdominal cavity and inferior vena cava of rats. Samples were harvested on day 14 and examined via immunohistochemical and immunofluorescence analyses.

RESULTS

Silver hydrogel was found to decrease the foreign body reaction; after subcutaneous and abdominal cavity implantation in rats, the capsule was found to be thinner in the silver hydrogel group than in the control hydrogel group. The silver hydrogel group had fewer CD68-positive cells and proliferating cell nuclear antigen and interleukin-33 (IL-33) dual-positive cells than the control hydrogel group. Additionally, the silver hydrogel patch reduced the neointimal thickness after patch venoplasty in rats, and the number of IL-33- and IL-1β-positive cells was lower than that in the control patch.

CONCLUSION

Silver-loaded SA/HA hydrogel patches decreased the foreign body reaction and venous neointimal hyperplasia in rats by the inhibition of IL-33 expression.

Scalp wound management: a narrative review from a neurosurgical perspective

OBJECTIVE

This article aims to present a narrative review of current literature about the anatomical characteristics of the scalp as well as current practices in the management of surgical, traumatic and pressure injuries in the scalp, which are common in neurosurgery practice.

METHOD

We searched PubMed for publications and book chapters in English from 2011 to 2021. We also included commonly referenced papers that we considered relevant to the subject with publication before these dates. We used the search terms 'laceration,' and/or 'neurosurgery' and/or, 'pressure injury,' and/or 'craniotomy,' and/or 'surgical incision' in combination with 'scalp,' and/or 'wound care.' We also searched the reference lists of publications identified by the search strategy and selected those that we judged relevant.

RESULTS

We pre-selected 52 articles that covered various aspects of anatomy, pathophysiology, scalp wound management, or general wound care that we considered applied to the anatomical region of our interest. After abstract review, we selected 34 articles that met our search criteria and were included in our review.

CONCLUSION

There is limited evidence regarding classification and care of scalp wounds. As a result, many of the current practices for scalp wound management are based on evidence derived from studies involving different anatomical regions, not considering its particular anatomy, vasculature and microbiome. Further research is needed for more comprehensive and effective protocols for the management of scalp injuries. However, this present review proposes responses to the identified gaps concerning the management of scalp wounds.

Nanocrystalline Silver Layer of Knitted Polyester Outperforms Other Silver-Containing Wound Dressings in an In Vitro Wound Model

Background Silver possesses cytotoxic properties against many microorganisms and is regularly used in wound care. Current evidence supporting the use of one type of silver-containing wound dressing (SCWD) is insufficient. Materials and methods To examine the ability of selected SCWDs to inhibit the growth of two strains of bacteria (Escherichia coli and Staphylococcus aureus) commonly found in wounds, an in vitro wound model was used. Bacteria were applied to the surface of nutrient agar, and a piece of each SCWD was applied to the bacteria. The plates were incubated at 37°C overnight. The zone of inhibition (ZI) around each SCWD was measured in cm2. Results The mean ZI for Acticoat Flex-3 on E. coli was 1.59 ± 0.15 cm2, which was significantly greater than that observed for Aquacel Ag (p<0.001), Mepilex Ag (p<0.0001), Mepitel Ag (p<0.001), Optifoam (p<0.0001), and Tegaderm Alginate Ag (p<0.01), but statistically indistinguishable from Maxorb II Ag. The mean ZI on S. aureus was 1.21 ± 0.16 cm2, which was greater than Aquacel Ag (p<0.05), Mepilex (p<0.0001), Optifoam (p<0.0001), and Tegaderm Alginate Ag (p<0.05), but statistically indistinguishable from Maxorb II Ag or Mepitel Ag. Conclusion Of the SCWDs tested, Acticoat Flex-3 demonstrated the most robust antimicrobial effect. Herein, we show that Acticoat Flex-3 may provide the most wound protection against bacterial infection. In conclusion, these data provide clinicians with additional independent evidence to inform their clinical practice on the use of specific wound dressings.

Silver-Based Dressings in the Prevention of the Incisional Surgical Site Infection: A Prospective Multicenter Observational Controlled Trial

Background: A new silver-based dressing has been designed to reduce surgical sited infections. Patients and Methods: A prospective multicenter observational study was conducted from January 2020 to October 2021. Patients with and without silver-based dressing after surgical incision were observed and their data analyzed. The study aimed to assess the incidence of incisional surgical site infection and primary healing after general surgery procedures. Results: Overall, 218 patients with silver-based (n = 109) and conventional silver-free dressing (n = 109) were analyzed. Surgical site infection (SSI) and primary incision healing were reported in 10 (9.2%) versus 21 (19.3%) (p = 0.037) and in 95 (87.2%) versus 86 (78.9%) (p = 0.107) patients treated with and without silver-based dressing, respectively. Conclusions: Silver-based dressing demonstrated a lower incidence of incisional SSI and improved primary healing in comparison with patients in whom conventional non-silver-based dressing has been used.

An Advanced Surgical Dressing for High-risk Patients Undergoing Breast Cancer Surgery: a Case-control Study

Oncological breast surgeries, classified as breast conserving surgery, oncoplastic surgery, and mastectomies (standard or with tissue sparing and reconstruction), are burdened with an overall complication rate up to 33%. Aquacel Ag Surgical is a combined hydrofiber-hydrocolloids dressing. The aim of this study is to evaluate the incidence of surgical site complications in patients presenting with three or more risk factors (or two, of which at least one classified as "high risk"), undergoing breast cancer surgery with/without reconstruction, comparing advanced (Aquacel Ag Surgical) with traditional dressing.

METHODS

This is a retrospective, monocentric, case-control study based at the breast unit of the Città della Salute e della Scienza Hospital of Turin, Italy. Forty-two patients who underwent breast surgeries and met the inclusion criteria were enrolled, from February 1 to July 31, 2018. The primary endpoint was comparing the incidence of surgical site complications (skin alterations, infection, and wound dehiscence) in the two groups. The secondary endpoints were evaluating patient's quality of life, aesthetic outcomes, and compliance to the dressings.

RESULTS

The distribution of risk factors at the baseline between the two groups was balanced, without statistically significant differences. Wound complications' incidence at 1 week was lower in the advanced dressing group (P = 0.015). On the bivariate descriptive analysis, advanced dressing proved to be easier to remove for the operator (P = 0.026). The aesthetic outcomes vouched for better scores in the advanced dressing group.

CONCLUSION

In the presented study Aquacel Ag Surgical dressing reduces surgical site complications in the first week after surgery in patients affected by three or more risk factors (or two with at least one classified as "high risk").

Treating post-renal transplant surgical site infection with combination therapy: a case study

Surgical site infection (SSI) is one of the most common and debilitating complications of surgery. The risk of SSI rises if the patient has underlying health-related risk factors. This article reports on the complicated case of 61-year-old female with a history of obesity and diabetes. She was diagnosed with end-stage renal disease (ESRD) and had been receiving haemodialysis since 2012. She underwent a kidney transplant and developed a multidrug-resistant Pseudomonas aeruginosa SSI following surgery. She experienced delayed wound healing with a partially dehisced incision. Despite conventional wound care, there was no progress in wound healing. The authors combined sharp debridement, irrigation and antibiotic therapy with a silver-containing antimicrobial dressing for 1 month. Her SSI improved significantly and she returned to theatre for wound closure. The patient recovered well and was discharged from the hospital after suture removal. Wound care professionals can use combination therapies to manage SSIs effectively and reduce patient and healthcare costs.

A new silver dressing, StopBac, used in the prevention of surgical site infections

Ideal dressings of surgical wounds should provide moist, semi-permeable, and antiseptic environments for optimal wound healing. To maximise patient comfort, surgical dressings must be hypoallergenic, not restrict movement, and allow patients to manage their personal hygiene. From the aspect of health care personnel, dressings should enable visual monitoring of the wound without the need for removing them, thus reducing the number of dressing changes. The active antimicrobial effect of silver cations has been demonstrated by many studies. StopBac is a unique surgical dressing based on the sol-gel process. Silver cations are bound in a colloidal solution in an organic-inorganic hybrid organosilicate oligomer. This gel is deposited on a pad using spray atomisation. The result is a polymer nanolayer matrix with prolonged and controlled release of silver ions. This pad forms part of a waterproof hypoallergenic transparent adhesive bandage. The goal of this study was to prospectively evaluate the ability of StopBac to prevent surgical site infections (SSIs) in patients after abdominal surgery. The secondary goal was to compare costs and determine the properties of this new material. A total of 32 patients were included in the study. The patients were followed up until their surgical wounds healed completely. An SSI occurred only in one patient.

Editor's Choice - Systematic Review and Meta-Analysis of Wound Adjuncts for the Prevention of Groin Wound Surgical Site Infection in Arterial Surgery

OBJECTIVE

Groin incision surgical site infections (SSIs) following arterial surgery are common and are a source of considerable morbidity. This review evaluates interventions and adjuncts delivered immediately before, during, or after skin closure, to prevent SSIs in patients undergoing arterial interventions involving a groin incision.

DATA SOURCES

MEDLINE, EMBASE, and CENTRAL databases were searched.

REVIEW METHODS

This review was undertaken according to established international reporting guidelines and was registered prospectively with the International prospective register of systematic reviews (CRD42020185170). The MEDLINE, EMBASE, and CENTRAL databases were searched using pre-defined search terms without date restriction. Randomised controlled trials (RCTs) and observational studies recruiting patients with non-infected groin incisions for arterial exposure were included; SSI rates and other outcomes were captured. Interventions reported in two or more studies were subjected to meta-analysis.

RESULTS

The search identified 1 532 articles. Seventeen RCTs and seven observational studies, reporting on 3 747 patients undergoing 4 130 groin incisions were included. A total of seven interventions and nine outcomes were reported upon. Prophylactic closed incision negative pressure wound therapy (ciNPWT) reduced groin SSIs compared with standard dressings (odds ratio [OR] 0.34, 95% CI 0.23 - 0.51; p < .001, GRADE strength of evidence: moderate). Local antibiotics did not reduce groin SSIs (OR 0.60 95% CI 0.30 - 1.21 p = .15, GRADE strength: low). Subcuticular sutures (vs. transdermal sutures or clips) reduced groin SSI rates (OR 0.33, 95% CI 0.17 - 0.65, p = .001, GRADE strength: low). Wound drains, platelet rich plasma, fibrin glue, and silver alginate dressings did not show any significant effect on SSI rates.

CONCLUSION

There is evidence that ciNPWT and subcuticular sutures reduce groin SSI in patients undergoing arterial vascular interventions involving a groin incision. Local antibiotics did not reduce groin wound SSI, although the strength of this evidence is lower. No other interventions demonstrated a significant effect.

Current Strategies in Prevention of Postoperative Infections in Spine Surgery

STUDY DESIGN

Narrative review.

OBJECTIVES

Postoperative surgical site infections (SSIs) are among the most common acute complications in spine surgery and have a devastating impact on outcomes. They can lead to increased morbidity and mortality as well as greater economic burden. Hence, preventive strategies to reduce the rate of SSIs after spine surgery have become vitally important. The purpose of this article was to summarize and critically analyze the available evidence related to current strategies in the prevention of SSIs after spine surgery.

METHODS

A literature search utilizing Medline database was performed. Relevant studies from all the evidence levels have been included. Recommendations to decrease the risk of SSIs have been provided based on the results from studies with the highest level of evidence.

RESULTS

SSI prevention occurs at each phase of care including the preoperative, intraoperative, and postoperative periods. Meticulous patient selection, tight glycemic control in diabetics, smoking cessation, and screening/eradication of Staphylococcus aureus are some of the main preoperative patient-related preventive strategies. Currently used intraoperative measures include alcohol-based skin preparation, topical vancomycin powder, and betadine irrigation of the surgical site before closure. Postoperative infection prophylaxis can be performed by administration of silver-impregnated or vacuum dressings, extended intravenous antibiotics, and supplemental oxygen therapy.

CONCLUSIONS

Although preventive strategies are already in use alone or in combination, further high-level research is required to prove their efficacy in reducing the rate of SSIs in spine surgery before evidence-based standard infection prophylaxis guidelines can be built.

Silver in Wound Care-Friend or Foe?: A Comprehensive Review

Due to its strong antimicrobial activity, silver is a commonly used adjunct in wound care. However, it also has the potential to impair healing by exerting toxic effects on keratinocytes and fibroblasts. The published literature on the use of silver in wound care is very heterogeneous, making it difficult to generate useful treatment guidelines.

METHODS

A search of high-quality studies on the use of silver in wound care was performed on PubMed. A detailed qualitative analysis of published articles was performed to evaluate the evidence for the use of silver in infected wounds, clean wounds, burns, and over closed surgical incisions.

RESULTS

Fifty-nine studies were included in this qualitative analysis. We found that, overall, the quality of the published research on silver is poor. While there is some evidence for short-term use of dressings containing nanocrystalline silver in infected wounds, the use of silver-containing dressings in clean wounds and over closed surgical incisions is not indicated. Negative-pressure wound therapy accelerates the healing of contaminated wounds, especially when silver is used as an adjunct. For burns, silver sulfadiazine slows healing and should not be used. Instead, nanocrystalline silver, or alternatives such as octenidine and polyhexanide, lead to less infection and faster healing.

CONCLUSIONS

In infected wounds, silver is beneficial for the first few days/weeks, after which nonsilver dressings should be used instead. For clean wounds and closed surgical incisions, silver confers no benefit. The ideal silver formulations are nanocrystalline silver and silver-coated polyurethane sponge for negative-pressure wound therapy. Silver sulfadiazine impairs wound healing. Proper use of silver-containing dressings is essential to optimize wound healing.