Negative pressure wound therapy with instillation and dwell time in debridement of fibrinous leg ulcers.

OBJECTIVE: In conjunction with appropriate wound care, negative pressure wound therapy with instillation and dwell time (NPWTi-d) may be used as an adjunct therapy for acute or hard-to-heal (chronic) wounds, especially when infected. However, there are very few data on the use of NPWTi-d in the treatment of fibrinous wounds that are difficult to debride mechanically. The main objective of this study was to describe changes in the fibrin area of such wounds, before and after treatment with NPWTi-d. METHOD: This was a monocentric, observational, prospective pilot study evaluating the NPWTi-d medical device. Eligible patients included in the study were those with hard-to-heal lower limb ulcers who had previously undergone unsuccessful specific debridement treatment for their wound, with failure of manual mechanic debridement for at least six weeks' duration, and whose wounds had a fibrinous surface area of >70% of the total wound surface area. The primary endpoint was the difference in the percentage of fibrinous surface area before and after treatment. RESULTS: A total of 14 patients who received treatment for lower limb ulcers between October 2017 and August 2019 were included in the study. There was a significant shrinkage rate of the fibrinous wound surface between the start and end of treatment (83.6±14.5% and 32.2±19.7%, respectively; p<0.001). CONCLUSION: This study showed a significant decrease in fibrin area in wounds treated with NPWTi-d, with good tolerance. We believe that NPWTi-d has its place in the multidisciplinary management of patients with hard-to-heal ulcers. Additional randomised studies are required to confirm these findings. DECLARATION OF INTEREST: The authors have no conflicts of interest.

Effect of quality nursing intervention on wound healing in patients with burns: A meta-analysis.

This meta-analysis aimed to explore the effects of quality nursing intervention on wound healing in patients with burns. A computerised search was conducted for randomised controlled trials (RCTs) on the effect of quality nursing intervention on wound healing in patients with burns in the PubMed, Embase, Google Scholar, Cochrane Library, China National Knowledge Infrastructure and Wanfang databases from the date of database inception to November 2023. Two researchers independently screened the literature, extracted data and performed quality assessment based on the inclusion and exclusion criteria. Stata 17.0 software was used for the data analysis. Twenty-nine RCTs involving 2637 patients with burns were included. The meta-analysis revealed that compared with conventional nursing, the implementation of quality nursing intervention in patients with burns significantly shortened the wound healing time (standardised mean difference [SMD] = -2.93, 95% confidence interval [CI]: -3.44 to -2.42, p < 0.001). The incidence of wound infections (odds ratio [OR] = 0.14, 95% CI: 0.07-0.27, p < 0.001) and complications (OR = 0.16, 95% CI: 0.11-0.23, p < 0.001) was also reduced significantly. This meta-analysis shows that applying quality nursing interventions in patients with burns can significantly shorten the wound healing time and reduce the incidence of wound infection and complications, thus promoting early patient recovery.

Cytotoxicity and concentration of silver ions released from dressings in the treatment of infected wounds: a systematic review.

Introduction: Silver-releasing dressings are used in the treatment of infected wounds. Despite their widespread use, neither the amount of silver released nor the potential in vivo toxicity is known. The aim of this study was to evaluate the cytotoxic effects and the amount of silver released from commercially available dressings with infected wounds. Methods: The review was conducted according to the PRISMA statement. The Web of Science, PubMed, Embase, Scopus, and CINAHL databases were searched for studies from 2002 through December 2022. The criteria were as follows: population (human patients with infected wounds); intervention (commercial dressings with clinical silver authorized for use in humans); and outcomes (concentrations of silver ions released into tissues and plasma). Any study based on silver-free dressings, experimental dressings, or dressings not for clinical use in humans should be excluded. According to the type of study, systematic reviews, experimental, quasi-experimental, and observational studies in English, Spanish, or Portuguese were considered. The quality of the selected studies was assessed using the JBI critical appraisal tools. Studies that assessed at least 65% of the included items were included. Data were extracted independently by two reviewers. Results: 740 articles were found and five were finally selected (all of them quasi-experimental). Heterogeneity was found in terms of study design, application of silver dressings, and methods of assessment, which limited the comparability between studies. Conclusion: In vivo comparative studies of clinical dressings for control of infection lack a standardized methodology that allows observation of all the variables of silver performance at local and systemic levels, as well as evaluation of its cytotoxicity. It cannot be concluded whether the assessed concentrations of released silver in commercial dressings for the topical treatment of infected wounds are cytotoxic to skin cells. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351041, PROSPERO [CRD42022351041].

Negative Pressure Wound Therapy With and Without Instillation in Necrotizing Soft Tissue Infections.

Background: Necrotizing soft tissue infections (NSTIs) are rare but deadly infections that require early and often extensive surgical debridement. After debridement, patients frequently have substantial morbidity because of large, open wounds. Hypothesis: Negative pressure wound therapy with instillation (NPWTi) results in higher wound closure rates compared with traditional negative pressure wound therapy (NPWT) or wet to dry dressings (moist wound care dressing). Patients and Methods: A prospectively maintained Acute and Critical Care Surgery database spanning 2008-2018 was queried for patients with a diagnosis of necrotizing fasciitis, Fournier gangrene, or gas gangrene. Data were collected on patient comorbidities, operative management, and clinical outcomes. Patients were stratified by use of moist wound care dressing, traditional NPWT, or NPWTi. Data were analyzed using analysis of variance (ANOVA), χ2, and logistic regression. Results: During the 10-year study period, patients were treated for NSTI; 173 were managed with moist wound care dressing, 150 with NPWT, and 48 with NPWTi. Patients were similar in terms of demographics, body mass index (BMI), diabetes mellitus, and smoking rates. Overall, complication rates were not substantially different, but mortality was higher in the moist wound care dressing group (16.2% vs. 10.7% NPWT vs. 2.1% NPWTi; p = 0.02). In the moist wound care dressing group, 81.5% of patients had an open wound at discharge compared with 52.7% of the NPWT group and only 14.6% of the NPWTi group (p < 0.001). On multivariable regression, NPWTi was associated with closure rates five times higher than the NPWT group (odds ratio [OR], 5.28; 95% confidence interval [CI], 2.40-11.61; p < 0.001) after controlling for smoking status, intravenous drug use, number of operations, and involvement of the most common region of the body. Conclusions: Negative pressure wound therapy with instillation is associated with higher rates of wound closure without increasing complication rates in patients with NSTI compared with traditional NPWT or moist wound care dressing. Although prospective studies are needed, this indicates the potential to improve patient quality of life through reduced pain and outpatient home health needs.

Biofilm therapy for chronic wounds.

Chronic wounds have been a major factor of serious harm to global public health. At present, it is known that almost all chronic wounds contain biofilms, which seriously hinder the healing process. Removal of biofilms can effectively promote the healing of chronic wounds. As the study of wound biofilms deepens, many new treatment methods have emerged, thus bringing revolutionary means for the treatment of chronic wound biofilm. This review summarizes various methods for the treatment of chronic wound biofilm worldwide to provide a theoretical summary and practical basis for the selection of suitable wound biofilm treatment methods in clinical practice.

The efficacy and safety of non-surgical treatment of diabetic foot wound infections and ulcers: A systemic review and meta-analysis.

This meta-analysis evaluates the efficacy and safety of non-surgical treatments for diabetic foot ulcers and infections. After a rigorous literature review, seven studies were selected for detailed analysis. The findings demonstrate that non-surgical treatments significantly reduce wound infection rates (standardized mean difference [SMD] = -15.15, 95% confidence interval [CI]: [-19.05, -11.25], p < 0.01) compared to surgical methods. Ulcer healing rates were found to be comparable between non-surgical and surgical approaches (SMD = 0.07, 95% CI: [-0.38, 0.51], p = 0.15). Importantly, the rate of amputations within 6 months post-treatment was significantly lower in the non-surgical group (risk ratio [RR] = 0.19, 95% CI: [0.09, 0.41], p < 0.01). Additionally, a lower mortality rate was observed in patients treated non-surgically (RR = 0.28, 95% CI: [0.13, 0.59], p < 0.01). These results affirm the effectiveness and safety of non-surgical interventions in managing diabetic foot ulcers, suggesting that they should be considered a viable option in diabetic foot care.

Safety and efficacy of a phage cocktail on murine wound infections caused by carbapenem-resistant Klebsiella pneumoniae.

OBJECTIVES: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a leading pathogen causing difficult-to-treat, healthcare-associated wound infections. Phages are an alternative approach against CRKP. This study established murine wound infection models with a CRKP clinical strain of sequence type 11 and capsular type KL64, which is the dominant type in China, carrying genes encoding KPC-2 and NDM-1 carbapenemases. METHODS: A cocktail was made comprising three lytic phages of different viral families against the strain. The phage cocktail restricted bacterial growth for 10 hours in vitro. The efficacy and safety of the phage cocktail in treating a murine wound CRKP infection were then evaluated. Mice were randomly assigned into four groups (16 for each) comprising a phage treatment group, infected with bacteria and 30 minutes later with phages, and three control groups administered with PBS (negative control), bacteria (infection control), or phages (phage control) on the wound. Wound tissues were processed for counting bacterial loads on days 1, 3, and 7 post-infection and examined for histopathological change on days 3 and 7. Two remaining mice in each group were monitored for wound healing until day 14. RESULTS: Compared with the infection control group, the wound bacterial load in the phage treatment group decreased by 4.95 × 102 CFU/g (> 100-fold; P < 0.05) at day 7 post-treatment, and wounds healed on day 10, as opposed to day 14 in the infection control group. No adverse events associated with phages were observed. CONCLUSION: The phage cocktail significantly reduced the wound bacterial load and promoted wound healing with good safety.

Intelligent wound dressing for simultaneous in situ detection and elimination of pathogenic bacteria.

Wound infections hinder the healing process and potentially result in life-threatening complications, which urgently require rapid and timely detection and treatment pathogens during the early stages of infection. Here, an intelligent wound dressing was developed to enable in situ detection and elimination of pathogenic bacteria through a combination of point-of-care testing and antibacterial photodynamic therapy technology. The dressing is an injectable hydrogel composed of carboxymethyl chitosan and oxidized sodium alginate, with addition of 4-methylumphulone beta-D-glucoside (MUG) and up-converted nanoparticles coated with titanium dioxide (UCNPs@TiO2). The presence of bacteria can be visually detected by monitoring the blue fluorescence of 4-methylumbellione, generated through the reaction between MUG and the pathogen-associated enzyme. The UCNPs@TiO2 photosensitizers were synthesized and demonstrated high antibacterial activity through the generation of reactive oxygen species when exposed to near-infrared irradiation. Meanwhile, a smartphone-based portable detection system equipped with a self-developed Android app was constructed for in situ detection of pathogens in mere seconds, detecting as few as 103 colony-forming unit. Additionally, the dressing was tested in a rat infected wound model and showed good antibacterial activity and pro-healing ability. These results suggest that the proposed intelligent wound dressing has potential for use in the diagnosis and management of wound infections. STATEMENT OF SIGNIFICANCE: An intelligent wound dressing has been prepared for simultaneous in situ detection and elimination of pathogenic bacteria. The presence of bacteria can be visually detected by tracking the blue fluorescence of the dressing. Moreover, a smartphone-based detection system was constructed to detect and diagnose pathogenic bacteria before reaching the infection limit. Meanwhile, the dressing was able to effectively eliminate key pathogenic bacteria on demand through antibacterial photodynamic therapy under NIR irradiation. The proposed intelligent wound dressing enables timely detection and treatment of infectious pathogens at an early stage, which is beneficial for wound management.

Bacteriophage Treatment of Infected Diabetic Foot Ulcers.

Diabetic foot ulcers occur as a common complication of diabetes. The concomitant infection significantly delays the healing of the ulcers. Antibiotic treatment of infected ulcers is complicated by the formation of microbial biofilms, which are often heterogeneous and resistant to antibiotics. Bacteriophage therapy is considered an additional approach to the treatment of infected wounds. Here, we describe the basic method of application of bacteriophages for the treatment of infected diabetic foot ulcers, including very large ones.

Potential antibacterial activity and healing effect of topical administration of bone marrow and adipose mesenchymal stem cells encapsulated in collagen-fibrin hydrogel scaffold on full-thickness burn wound infection caused by Pseudomonas aeruginosa.

Burns injuries are prone to hospital-acquired infections, and Pseudomonas aeruginosa is one of the most common causes of mortality and morbidity in patients with burn injuries. Thus, this study aimed to analyze the effects of topical treatment with bone marrow (BM-MSC) and adipose mesenchymal stem cells (AD-MSC) encapsulated in collagen and fibrin scaffolds in a Balb/c model of burn wound infection. Extraction of stem cells from adipose and bone marrow tissue of rats was performed and cells were characterized using standard methods. Then, collagen, fibrin and collagen-fibrin scaffolds were constructed and the extracted cells were encapsulated in all three scaffolds. Then, 3rd degree burn was induced in mice and 1.5 × 108 (CFU/ml) of P. aeruginosa was introduced to the burn wound. Subsequently, after 24 h of inducing wound infection, encapsulated MSCs were introduced as dressings to burn wound infection and microbial load as well as rate of wound infection healing was measured. The results of this study showed that the use of BM-MSC and AD-MSC encapsulated in collagen-fibrin scaffold reduced the bacteria load down to 54 and 21 CFU/gr, respectively (P < 0.05). Moreover, BM-MSC and AD-MSC encapsulated in collagen-fibrin showed 80% and 75% wound healing, respectively (P < 0.05). Also, we found no significant between cell origin and healing. Encapsulation of MSCs into collagen-fibrin scaffolds could be effective not only against P. aeruginosa infection, but also healing and regeneration of burn wound.

Development and use of a porcine model with clinically relevant chronic infected wounds.

Chronic ischemic wounds affect millions of people causing significant pain and disability. They can be considered to be stalled in the inflammatory stage and cannot heal without additional measures. A valid animal model is necessary to evaluate the efficacy of topical wound healing therapies and wearable technologies. A porcine model, although higher in cost, maintenance, and space requirements, is superior to the commonly used rodent or rabbit model for wound healing. Previous studies have shown that pig wounds have greater similarity to human wounds in responses to a variety of treatments, including wound dressings and antibiotics. The current study created a porcine model of large chronic wounds to assess a wearable electroceutical technology, with monitoring of healing variables and infection. Electroceutical therapy is the only adjunctive treatment recommended for chronic wound therapy. A porcine model of large chronic wounds of clinically realistic size was created and utilized to evaluate a wearable electroceutical biotechnology. Multivariate non-invasive assessment was used to monitor wound progression over multiple timepoints. Outcomes suggest that a wearable electrostimulation bandage, has the potential to offer therapeutic benefit in human wounds. The tested wearable device provides the same proven effectiveness of traditional electroceutical therapy while mitigating commonly cited barriers, including substantial time requirements, and availability and complexity of currently available equipment, preventing its implementation in routine wound care. The model is also appropriate for evaluation of other wearables or topical therapeutics.

Comparison of open and closed burn wound dressing applications with tissue culture sampling.

BACKGROUND: Secondary infections are the leading cause of death in burn patients. The purpose of this study is to evaluate the effects of open and closed burn dressings on the development of secondary infections. METHODS: Tissue cultures were obtained from the burn sites of 56 patients between the ages of 18 and 65 who were admitted to our burn unit between December 2022 and January 2023, on days 3 and 7. The impact of the demographic features of the patients, the characteristics of the burn wound, the dressing type, and the first intervention strategies given to the burn wound on the development of wound infection were evaluated. RESULTS: There was no statistically significant difference between the open- and closed-dressing groups in terms of cultural positiv-ity (P>0.05). A statistically significant difference (P=0.019) was found between the groups in terms of culture positivity among those whose wounds were cleansed with warm water as the initial intervention after a burn and those whose wounds were not. CONCLUSION: Even though the main impacts of the patient's variables on the development of a wound infection are recognized, it has been found that the appropriate and successful first intervention in a burn wound is also quite important.

The influence of negative pressure wound therapy on bacterial and fungal growth.

BACKGROUND: The use of negative pressure wound therapy (NPWT) in superinfected wounds is controversial. The mechanism of action is unclear, but recent studies have shown lower atmospheric oxygen levels within the dressing. Therefore, different oxygen-favoring bacteria and fungi might benefit or face impaired thriving conditions. The aim of this in vitro study is to investigate the influence of NPWT on bacterial and fungal growth. METHODS: Salmonella enterica subsp. enterica serovar Typhimurium, Pseudomonas aeruginosa and Candida albicans strains were cultured on concentrated agars and attached to a standard NPWT-device. After 48 hours, colonies were separately harvested from the agar and foam. Optical density (OD) was obtained in order to estimate bacterial loads. RESULTS: For all tested microorganisms, no overall significant differences were found compared to controls. Subanalysis showed lower OD levels from the agar beneath the foam in the NPWT-group. CONCLUSION: NPWT removed bacteria and fungi from the wound surface but accumulation is found within the foam. The use of NPWT showed no influence on bacterial or fungal growth selection. With superinfected wounds, the use of NPWT should thoroughly be evaluated as toxins and virulence factors may not fully be evacuated.

Effect of negative pressure sealing and drainage (VSD) technique on wound infection in adult orthopaedics and its influence fitness indicator

Objective: To investigate the effect of vacuum sealing drainage (VSD) in the healing of adult orthopedic wound infection, and to explore the effect of intervention on white blood cell (WBC) and C-reactive protein (CRP) levels; Methods: 80 adult Athlete patients with orthopedic wound infection who were healed in our hospital from January 2020 to January 2022 were retrospectively opted as the research subjects, and were divided into the VSD cluster (n=40, receiving VSD technology) and the control cluster according to their healing methods (CG, n=40, receiving conventional gauze dressing healing), the variations in WBC and CRP between the two clusters before healing, on the 5th day of healing, on the 10th day of healing, and on the 15th day of healing were contrasted between the two clusters, and the wound surfaces of the two clusters of athlete patients were contrasted at the above time points. The variation in appearance, the variation in the bacterial negative rate of the wound surface after the intervention was contrasted, and the wounded limb marks of the two clusters of athlete patients were followed up; Results: (1) On the 5th day, 10th day and 15th day of healing, the WBC and CRP levels in the VSD cluster were notably lower than those within the control cluster (P < 0.05); (2) On the 5th day, 10th day and 15th day of healing, the wound appearance marks in the VSD cluster were notably upper than those within the control cluster, and the variation between the clusters was notable (P < 0.05); (3) The wound bacterial conversion rates within the study cluster were 40.00%, 70.00% and 95.00% at 1 month, 2 months and 3 months after operation, respectively, which were notably upper than 17.50%, 47.50% and 80.00% within the control cluster, and the variation between the clusters was notable (P < 0.05); (4) At 1 month, 2 months and 3 months after operation, the Puno limb marks within the study cluster were notably upper than those within the control cluster (AU)

Chitosan-Based Hydrogels for Infected Wound Treatment.

Wound infections slow down the healing process and lead to complications such as septicemia, osteomyelitis, and even death. Although traditional methods relying on antibiotics are effective in controlling infection, they have led to the emergence of antibiotic-resistant bacteria. Hydrogels with antimicrobial function become a viable option for reducing bacterial colonization and infection while also accelerating healing processes. Chitosan is extensively developed as antibacterial wound dressings due to its unique biochemical properties and inherent antibacterial activity. In this review, the recent research progress of chitosan-based hydrogels for infected wound treatment, including the fabrication methods, antibacterial mechanisms, antibacterial performance, wound healing efficacy, etc., is summarized. A concise assessment of current limitations and future trends is presented.

Infections in Burn Patients.

Infections are the leading cause of mortality in burn patients who survive their initial resuscitation. Burn injury leads to immunosuppression and a dysregulated inflammatory response which can have a prolonged impact. Early surgical excision along with support of the multidisciplinary burn team has improved mortality in burn patients. The authors review diagnostic and therapeutic challenges as well as strategies for management of burn related infections.

Wound Dressing Modifications for Accelerated Healing of Infected Wounds.

Infections that occur during wound healing involve the most frequent complications in the field of wound care which not only inhibit the whole process but also lead to non-healing wound formation. The diversity of the skin microbiota and the wound microenvironment can favor the occurrence of skin infections, contributing to an increased level of morbidity and even mortality. As a consequence, immediate effective treatment is required to prevent such pathological conditions. Antimicrobial agents loaded into wound dressings have turned out to be a great option to reduce wound colonization and improve the healing process. In this review paper, the influence of bacterial infections on the wound-healing phases and promising modifications of dressing materials for accelerated healing of infected wounds are discussed. The review paper mainly focuses on the novel findings on the use of antibiotics, nanoparticles, cationic organic agents, and plant-derived natural compounds (essential oils and their components, polyphenols, and curcumin) to develop antimicrobial wound dressings. The review article was prepared on the basis of scientific contributions retrieved from the PubMed database (supported with Google Scholar searching) over the last 5 years.

Autocatalytically hydroxyl-producing composite wound dressing for bacteria-infected wound healing.

The creation of wound dressings with low drug resistance and broad-spectrum antibacterial capability is a key topic of scientific interest. To achieve this, a bactericidal wound dressing with the capacity to autocatalytically produce hydroxyl radicals (OH) was developed. The wound dressing was an electrospun PCL/gelatin/glucose composite fiber mesh (PGD) with functional iron-containing metal-organic framework (Fe-MOF) nanozymes. These functional nanozymes (G@Fe) were formed by coupling glucose oxidase (GOx) and Fe-MOF through amide bonds. These nanozymes enabled the conversion of glucose released from the PGD composite mesh into hydroxyl radicals via an autocatalytic cascade reaction to destroy bacteria. The antibacterial efficiency of wound dressings and their stimulation of tissue regeneration were assessed using a MRSA-infected skin wound infection model on the back of SD mice. The G@Fe/PGD wound dressing exhibited improved wound healing capacity and had comparable biosafety to commercial silver-containing dressings, suggesting a potential replacement in the future.

Biofilm and wound healing: from bench to bedside.

The bubbling community of microorganisms, consisting of diverse colonies encased in a self-produced protective matrix and playing an essential role in the persistence of infection and antimicrobial resistance, is often referred to as a biofilm. Although apparently indolent, the biofilm involves not only inanimate surfaces but also living tissue, making it truly ubiquitous. The mechanism of biofilm formation, its growth, and the development of resistance are ever-intriguing subjects and are yet to be completely deciphered. Although an abundance of studies in recent years has focused on the various ways to create potential anti-biofilm and antimicrobial therapeutics, a dearth of a clear standard of clinical practice remains, and therefore, there is essentially a need for translating laboratory research to novel bedside anti-biofilm strategies that can provide a better clinical outcome. Of significance, biofilm is responsible for faulty wound healing and wound chronicity. The experimental studies report the prevalence of biofilm in chronic wounds anywhere between 20 and 100%, which makes it a topic of significant concern in wound healing. The ongoing scientific endeavor to comprehensively understand the mechanism of biofilm interaction with wounds and generate standardized anti-biofilm measures which are reproducible in the clinical setting is the challenge of the hour. In this context of "more needs to be done", we aim to explore various effective and clinically meaningful methods currently available for biofilm management and how these tools can be translated into safe clinical practice.