A Silver-Coated Antimicrobial Barrier Dressing Used Postoperatively on Meshed Autografts: A Dressing Comparison Study

Plant-mediated synthesis of silver nanoparticles: unlocking their pharmacological potential-a comprehensive review

In recent times, nanoparticles have experienced a significant upsurge in popularity, primarily owing to their minute size and their remarkable ability to modify physical, chemical, and biological properties. This burgeoning interest can be attributed to the expanding array of biomedical applications where nanoparticles find utility. These nanoparticles, typically ranging in size from 10 to 100 nm, exhibit diverse shapes, such as spherical, discoidal, and cylindrical configurations. These variations are not solely influenced by the manufacturing processes but are also intricately linked to interactions with surrounding stabilizing agents and initiators. Nanoparticles can be synthesized through physical or chemical methods, yet the biological approach emerges as the most sustainable and eco-friendly alternative among the three. Among the various nanoparticle types, silver nanoparticles have emerged as the most encountered and widely utilized due to their exceptional properties. What makes the synthesis of silver nanoparticles even more appealing is the application of plant-derived sources as reducing agents. This approach not only proves to be cost-effective but also significantly reduces the synthesis time. Notably, silver nanoparticles produced through plant-mediated processes have garnered considerable attention in recent years due to their notable medicinal capabilities. This comprehensive review primarily delves into the diverse medicinal attributes of silver nanoparticles synthesized using plant-mediated techniques. Encompassing antimicrobial properties, cytotoxicity, wound healing, larvicidal effects, anti-angiogenesis activity, antioxidant potential, and antiplasmodial activity, the paper extensively covers these multifaceted roles. Additionally, an endeavor is made to provide an elucidated summary of the operational mechanisms underlying the pharmacological actions of silver nanoparticles.

Diverse nanocomposites as a potential dressing for diabetic wound healing

Wound healing is a programmed process of continuous events which is impaired in the case of diabetic patients. This impaired process of healing in diabetics leads to amputation, longer hospitalisation, immobilisation, low self-esteem, and mortality in some patients. This problem has paved the way for several innovative strategies like the use of nanotechnology for the treatment of wounds in diabetic patients. The use of biomaterials, nanomaterials have advanced approaches in tissue engineering by designing multi-functional nanocomposite scaffolds. Stimuli-responsive scaffolds that interact with the wound microenvironment and controlled release of bioactive molecules have helped in overcoming barriers in healing. The use of different types of nanocomposite scaffolds for faster healing of diabetic wounds is constantly being studied. Nanocomposites have helped in addressing specific issues with respect to healing and improving angiogenesis. Method: A literature search was followed to retrieve the articles on strategies for wound healing in diabetes across several databases like PubMed, EMBASE, Scopus and Cochrane database. The search was performed in May 2022 by two researchers independently. They keywords used were "diabetic wounds, nanotechnology, nanocomposites, nanoparticles, chronic diabetic wounds, diabetic foot ulcer, hydrogel". Exclusion criteria included insulin resistance, burn wound, dressing material.

Evidence for silver in wound care - meta-analysis of clinical studies from 2000-2015

BACKGROUND

Given that the scientific evidence for silver in wound care is generally considered insufficient, there is uncertainty among users regarding its clinical use.

MATERIAL AND METHODS

A group of experts evaluated the clinical studies on silver in wound management published from 2000-2015.

RESULTS

Overall, 851 articles were identified, 173 of which were included and categorized. There were 31 randomized controlled trials (RCTs) and eight cohort studies. Twenty-eight of these studies showed statistically significant outcome parameters in support of silver. While nine of these studies investigated burn injuries, 20 addressed other indications (venous leg ulcers: 9; pressure ulcers: 3; chronic wounds: 2; diabetic foot ulcer: 1; other types of wounds: 5). In 16 studies, the primary parameter was wound healing, whereas quality of life including pain was assessed in twelve studies; cost-effectiveness, in eight studies; reduction of bacterial load, in three studies. Based on these results, a treatment algorithm for the clinical use of silver in wound care has been developed.

CONCLUSIONS

The present meta-analysis shows that the evidence base for silver in wound management is significantly better than perceived in the current scientific debate. Thus, if used selectively and for a limited period of time, silver not only has antimicrobial effects but is also characterized by an improvement in quality of life and good cost-effectiveness.

Efficacy of Conventional and Liposomal Povidone-Iodine in Infected Mesh Skin Grafts: An Exploratory Study

Introduction

Infection is a major threat to wound healing and a leading cause of graft loss in patients undergoing meshed skin grafts (MSGs). Therefore, topical antisepsis is important in the overall treatment scheme.

Methods

An exploratory satellite group of 14 patients with infected MSGs were enrolled as part of a prospective, randomized, controlled, parallel-group, open-label, pilot Phase II study that investigated the efficacy and tolerability of 3% liposomal povidone–iodine hydrogel (PVP–ILH, Repithel^®; RepiGel^®) versus chlorhexidine gauze in non-infected MSGs. The satellite group included both patients with infected wound beds prior to grafting and patients with infection of a previously placed graft, with MSG sizes ranging from 50 to 1000 cm², who were randomized to treatment with (PVP–ILH) or 10% povidone–iodine ointment (Betaisodona^®; BETADINE^®). Medication was applied in a 2-mm layer and dressing changes with identical application of study medication took place daily. Wounds were evaluated by photoplanimetry, microbiologically and subjectively by patients and physicians.

Results

The results for the main study group have been reported previously. In the satellite group, both PVP–ILH and povidone–iodine ointment performed remarkably well with respect to lowering the bacterial count and restoring wound healing, with different emphasis. Povidone–iodine ointment showed excellent antibacterial efficacy with no detectable microorganisms by Day 10, and rapid re-epithelialization (mean 90% by Day 6). PVP–ILH also demonstrated rapid re-epithelialization (mean 72% by Day 6) with a trend towards improved subjective measures of wound healing quality. Four patients (40%) receiving PVP–ILH experienced partial graft loss (10–15% of total MSG area); no patients in the povidone–iodine ointment group experienced graft loss.

Conclusion

Our results suggest that povidone–iodine ointment has a strong role in managing infected wounds, especially when a high concentration of povidone–iodine may be warranted, while PVP–ILH indicated similar beneficial results on markers of wound healing quality in larger infected wounds.

Trial Registration

The trial was conducted prior to mandatory registration of drug products, PVP–ILH represents a medicated device in the EU and many other countries.

Funding

Mundipharma Research GmbH & Co. KG.

History and Advancement of Burn Treatments

Advances in burn care have accelerated within the last 50 years. The principal modalities of and approaches to burn treatment include dressings, antimicrobials, fluid resuscitation, burn wound excision, skin grafting, and use of skin substitutes. This review presents a historical outline of these approaches, their current status, and prospects for the future of burn care.

Fabrication and characterization of hydrocolloid dressing with silk fibroin nanoparticles for wound healing

Hydrocolloid dressings have been developed for many types of wound healing. In particular, dressing is a critical component in the successful recover of burn injuries, which causes a great number of people to not only suffer from physical but also psychological and economic anguish each year. Additionally, silk fibroin is the safest material for tissue engineering due to biocompatibility. In this study, we fabricated hydrocolloid dressings incorporating silk fibroin nanoparticles to enhance the efficacy of hydrocolloid dressing and then use this silk fibroin nanoparticle hydrocolloid dressing (SFNHD) in animal models to treat burn wounds. The structures and properties of SFNHD were characterized using tensile strength and Cell Counting Kit-8 assay. The results indicated the structural stability and the cellular biocompatibility of the hydrocolloid dressing suggesting that SFNHD can be applied to the treatment of wounds. To demonstrate the capacity of a silk fibroin hydrocolloid dressing to treat burn wounds, we compared SFNHD to gauze and Neoderm^®, a commercially available dressing. This study clearly demonstrated accelerated wound healing with greater wound structural integrity and minimal wound size after treatment with SFNHD. These observations indicate that SFNHD may be an improvement upon current standard dressings such as Gauze and Neoderm^® for burn wounds.

UV fluorescence excitation imaging of healing of wounds in skin: Evaluation of wound closure in organ culture model

BACKGROUND AND OBJECTIVE

Molecules native to tissue that fluoresce upon light excitation can serve as reporters of cellular activity and protein structure. In skin, the fluorescence ascribed to tryptophan is a marker of cellular proliferation, whereas the fluorescence ascribed to cross-links of collagen is a structural marker. In this work, we introduce and demonstrate a simple but robust optical method to image the functional process of epithelialization and the exposed dermal collagen in wound healing of human skin in an organ culture model.

MATERIALS AND METHODS

Non-closing non-grafted, partial closing non-grafted, and grafted wounds were created in ex vivo human skin and kept in culture. A wide-field UV fluorescence excitation imaging system was used to visualize epithelialization of the exposed dermis and quantitate wound area, closure, and gap. Histology (H&E staining) was also used to evaluate epithelialization.

RESULTS

The endogenous fluorescence excitation of cross-links of collagen at 335 nm clearly shows the dermis missing epithelium, while the endogenous fluorescence excitation of tryptophan at 295 nm shows keratinocytes in higher proliferating state. The size of the non-closing wound was 11.4 ± 1.8 mm and remained constant during the observation period, while the partial-close wound reached 65.5 ± 4.9% closure by day 16. Evaluations of wound gaps using fluorescence excitation images and histology images are in agreement.

CONCLUSIONS

We have established a fluorescence imaging method for studying epithelialization processes, evaluating keratinocyte proliferation, and quantitating closure during wound healing of skin in an organ culture model: the dermal fluorescence of pepsin-digestible collagen cross-links can be used to quantitate wound size, closure extents, and gaps; and, the epidermal fluorescence ascribed to tryptophan can be used to monitor and quantitate functional states of epithelialization. UV fluorescence excitation imaging has the potential to become a valuable tool for research, diagnostic and educational purposes on evaluating the healing of wounds. Lasers Surg. Med. 48:678-685, 2016. © 2016 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

Antibiotic prophylaxis for preventing burn wound infection

BACKGROUND

Infection of burn wounds is a serious problem because it can delay healing, increase scarring and invasive infection may result in the death of the patient. Antibiotic prophylaxis is one of several interventions that may prevent burn wound infection and protect the burned patient from invasive infections.

OBJECTIVES

To assess the effects of antibiotic prophylaxis on rates of burn wound infection.

SEARCH METHODS

In January 2013 we searched the Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid MEDLINE - In-Process & Other Non-Indexed Citations (2013); Ovid EMBASE; EBSCO CINAHL and reference lists of relevant articles. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

All randomised controlled trials (RCTs) that evaluated the efficacy and safety of antibiotic prophylaxis for the prevention of BWI. Quasi-randomised studies were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed the risk of bias, and extracted relevant data. Risk ratio (RR) and mean difference (MD) were estimated for dichotomous data and continuous data, respectively. When sufficient numbers of comparable RCTs were available, trials were pooled in a meta-analysis to estimate the combined effect.

MAIN RESULTS

This review includes 36 RCTs (2117 participants); twenty six (72%) evaluated topical antibiotics, seven evaluated systemic antibiotics (four of these administered the antibiotic perioperatively and three administered upon hospital admission or during routine treatment), two evaluated prophylaxis with non absorbable antibiotics, and one evaluated local antibiotics administered via the airway.The 11 trials (645 participants) that evaluated topical prophylaxis with silver sulfadiazine were pooled in a meta analysis. There was a statistically significant increase in burn wound infection associated with silver sulfadiazine compared with dressings/skin substitute (OR = 1.87; 95% CI: 1.09 to 3.19, I(2) = 0%). These trials were at high, or unclear, risk of bias. Silver sulfadiazine was also associated with significantly longer length of hospital stay compared with dressings/skin substitute (MD = 2.11 days; 95% CI: 1.93 to 2.28).Systemic antibiotic prophylaxis in non-surgical patients was evaluated in three trials (119 participants) and there was no evidence of an effect on rates of burn wound infection. Systemic antibiotics (trimethoprim-sulfamethoxazole) were associated with a significant reduction in pneumonia (only one trial, 40 participants) (RR = 0.18; 95% CI: 0.05 to 0.72) but not sepsis (two trials 59 participants) (RR = 0.43; 95% CI: 0.12 to 1.61).Perioperative systemic antibiotic prophylaxis had no effect on any of the outcomes of this review.Selective decontamination of the digestive tract with non-absorbable antibiotics had no significant effect on rates of all types of infection (2 trials, 140 participants). Moreover, there was a statistically significant increase in rates of MRSA associated with use of non-absorbable antibiotics plus cefotaxime compared with placebo (RR = 2.22; 95% CI: 1.21 to 4.07).There was no evidence of a difference in mortality or rates of sepsis with local airway antibiotic prophylaxis compared with placebo (only one trial, 30 participants).

AUTHORS' CONCLUSIONS

The conclusions we are able to draw regarding the effects of prophylactic antibiotics in people with burns are limited by the volume and quality of the existing research (largely small numbers of small studies at unclear or high risk of bias for each comparison). The largest volume of evidence suggests that topical silver sulfadiazine is associated with a significant increase in rates of burn wound infection and increased length of hospital stay compared with dressings or skin substitutes; this evidence is at unclear or high risk of bias. Currently the effects of other forms of antibiotic prophylaxis on burn wound infection are unclear. One small study reported a reduction in incidence of pneumonia associated with a specific systematic antibiotic regimen.

Nanomedicine: a primer for surgeons

The advances in science have resulted in the emergence of nanotechnology, which deals with the design and use of tools and devices of size 1-100 nm. The application of nanotechnologies to medicine is thus termed nanomedicine. Significant research has been focused on this new and exciting field and this review article will describe the basics of nanomedicine. This is followed by its experimental and clinical applications in diagnostics, drug therapy and regenerative medicine. Safety issues of in vivo use of nanomaterials are also discussed. In the future, it is foreseen that nanomedicine will facilitate the development of personalized medicine and will have a major impact on the delivery of better healthcare.

Silver: an age-old treatment modality in modern times

The use of silver as an antimicrobial for infection spans hundreds of years. The ancient Greeks and Romans used silver to disinfect their water and food supplies. Silver was also used in ancient times to treat burns and wounds as a wound dressing. Silver solutions were approved by the U.S. Food and Drug Administration in the 1920s. Since that time, silver has established itself as an effective and well-known treatment modality for and in the prevention of high-risk infection in clinical wound care (http://int.hansaplast.com/med-info/wound-care-beautiful-healing/silver-tech.html).

Topical silver for preventing wound infection

BACKGROUND

Silver-containing treatments are popular and used in wound treatments to combat a broad spectrum of pathogens, but evidence of their effectiveness in preventing wound infection or promoting healing is lacking.

OBJECTIVES

To establish the effects of silver-containing wound dressings and topical agents in preventing wound infection and healing of wounds.

SEARCH STRATEGY

We searched the Cochrane Wounds Group Specialised Register (6 May 2009); The Cochrane Central Register of Controlled Trials (CENTRAL) (2009 Issue 2); Ovid MEDLINE (1950 to April Week 4 2009); Ovid EMBASE (1980 to 2009 Week 18); EBSCO CINAHL (1982 to April Week 4 2009) and Digital Dissertations (to May 2009) for relevant trials. We contacted manufacturers and distributors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing silver-containing wound dressings and topical agents with silver-containing and non silver-containing comparators on uninfected wounds.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials, assessed risk of bias, and extracted data.

MAIN RESULTS

We identified 26 RCTs (2066 patients). Heterogeneity of treatments and outcomes precluded meta-analysis. We grouped results according to wound type, and silver preparation.BurnsThirteen trials compared topical silver (in a variety of formulations - including silver sulphadiazine (SSD) cream) with non-silver dressings. One trial showed fewer infections with silver nitrate when compared with a non-silver dressing, but three trials showed significantly more infection with SSD than with the non-silver dressing.Six trials compared SSD cream with silver-containing dressings. One showed significantly fewer infections with the silver-containing dressing (Hydron AgSD) compared with SSD, the remaining five found no evidence of a difference.One trial compared two silver-containing dressings, and showed a significantly lower infection rate with silver-coated gauze (Acticoat(R)) than with silver nitrate gauze.Other woundsSix trials compared SSD/silver-containing dressings with non-silver dressings (nine dressings in total). Most comparisons (seven) found no significant differences in infection rates; one trial in a variety of wounds exhibited significantly fewer infections with SSD/hydrocolloid, but another, in acute wounds, found significantly more infections with SSD. Only one comparison showed a significant reduction in healing time associated with a silver-containing hydrofibre dressing in diabetic foot ulcers.

AUTHORS' CONCLUSIONS

There is insufficient evidence to establish whether silver-containing dressings or topical agents promote wound healing or prevent wound infection; some poor quality evidence for SSD suggests the opposite.

Burns: what are the pharmacological treatment options?

BACKGROUND

Many advances have been made in the understanding and management of burn injury, dramatically increasing pharmacological decision options for burn care professionals. Since burn injury is so multi-faceted, these advances cross many injury processes, both acute and chronic.

OBJECTIVE

The purpose of this review was to highlight the advances and decision options across the entire scope of the burn injury process. The burn-related processes with the most significant pharmacological options of approved products are highlighted.

METHODS

The scope of the current research is the most pertinent literature, which has been summarized with the addition of a personal perspective.

RESULTS/CONCLUSIONS

Many advances over the past decade in multiple fields have made pharmacological options plentiful in burn care. That said, there are many problems for the burn patient which persist, making burn injury still the most severe form of trauma. These issues range from management of a catabolic state with involuntary weight loss in the critical burn to severe itching in the rehabilitating patient. There are also many more treatment options available today. Two key reasons stand out as the most prominent. One reason is the fact that burn care has become much more proactive, by searching out new approaches to solve old problems. Now the treatment approach is altering its focus on manipulating the course of a burn. Examples include the use of temporary skin substitutes in partial thickness or second degree burns, decreasing pain and increasing the healing rate. Another is the use of slow release silver dressing as the topical burn wound antimicrobial of choice, markedly reducing discomfort, the need for dressing changes and an overall decrease in infection. In larger, deeper burns, the approach has changed from the chronic management of an open burn wound to rapid excision and wound closure, eliminating the burn as a source of complications. In addition, there has been a very aggressive approach to controlling the profound hypermetabolic, catabolic response to burns, rather than simply treating the outcome of this predictable post-burn complication. Approaching psychosocial stress again by prevention rather than treatment of established problems is another example. The second reason for increased options and differences in management involves the mindset of those individuals taking care of burns. Tremendous differences in experience are involved in decision-making. Different opinions are based on the expertise and also the personal preferences of those managing the burn.

The year in burns 2007

In the year 2007, approximately 1000 original burn research articles were published in scientific journals using the English language. This article reviews approximately 90 of these which were deemed by the author to be the most important in terms of clinical burn care. Relevant topics include epidemiology, wound characterisation, critical care physiology, inhalation injury, infection, metabolism and nutrition, psychological considerations, pain management, rehabilitation, and burn reconstruction. Each selected article is mentioned briefly with editorial comment.

Development of a chitosan-based wound dressing with improved hemostatic and antimicrobial properties

Hemorrhage remains a leading cause of early death after trauma, and infectious complications in combat wounds continue to challenge caregivers. Although chitosan dressings have been developed to address these problems, they are not always effective in controlling bleeding or killing bacteria. We aimed to refine the chitosan dressing by incorporating a procoagulant (polyphosphate) and an antimicrobial (silver). Chitosan containing different amounts and types of polyphosphate polymers was fabricated, and their hemostatic efficacies evaluated in vitro. The optimal chitosan-polyphosphate formulation (ChiPP) accelerated blood clotting (p = 0.011), increased platelet adhesion (p=0.002), generated thrombin faster (p = 0.002), and absorbed more blood than chitosan (p < 0.001). Silver-loaded ChiPP exhibited significantly greater bactericidal activity than ChiPP in vitro, achieving a complete kill of Pseudomonas aeruginosa and a > 99.99% kill of Staphylococcus aureus consistently. The silver dressing also significantly reduced mortality from 90% to 14.3% in a P. aeruginosa wound infection model in mice. Although the dressing exerted severe cytotoxicity against cultured fibroblasts, wound healing was not inhibited. This study demonstrated for the first time, the application of polyphosphate as a hemostatic adjuvant, and developed a new chitosan-based composite with potent hemostatic and antimicrobial properties.