A cost and clinical effectiveness analysis among moist wound healing dressings versus traditional methods in home care patients with pressure ulcers

Impact of moist wound dressing on wound healing time: A meta-analysis

Among the assortment of available dressings aimed at promoting wound healing, moist dressings have gained significant popularity because of their ability to create an optimal environment for wound recovery. This meta-analysis seeks to compare the effects of moist dressing versus gauze dressing on wound healing time. A comprehensive literature search was conducted, encompassing publications up until April 1, 2023, across multiple databases including PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), and Cochrane Library. Stringent criteria were used to determine study inclusion and evaluate methodological quality. Statistical analyses were performed utilizing Stata 17.0. A total of 13 articles, encompassing 866 participants, were included in the analysis. The findings indicate that moist dressing surpasses gauze dressing in terms of wound healing time (standard mean difference [SMD] -2.50, 95% confidence interval [CI] -3.35 to -1.66, p < 0.01; I2  = 97.24%), wound site infection rate (odds ratio [OR] 0.30, 95% CI 0.17 to 0.54, p < 0.01; I2  = 39.91%), dressing change times (SMD -3.65, 95% CI -5.34 to -1.97, p < 0.01; I2  = 96.48%), and cost (SMD -2.66, 95% CI -4.24 to -1.09, p < 0.01; I2  = 94.90%). Subgroup analyses revealed possible variations in wound healing time based on wound types and regions. This study underscores the significant advantages associated with the use of moist dressings, including expedited wound healing, reduced infection rates, decreased frequency of dressing changes, and lower overall treatment costs.

Research advances in smart responsive-hydrogel dressings with potential clinical diabetic wound healing properties

The treatment of chronic and non-healing wounds in diabetic patients remains a major medical problem. Recent reports have shown that hydrogel wound dressings might be an effective strategy for treating diabetic wounds due to their excellent hydrophilicity, good drug-loading ability and sustained drug release properties. As a typical example, hyaluronic acid dressing (Healoderm) has been demonstrated in clinical trials to improve wound-healing efficiency and healing rates for diabetic foot ulcers. However, the drug release and degradation behavior of clinically-used hydrogel wound dressings cannot be adjusted according to the wound microenvironment. Due to the intricacy of diabetic wounds, antibiotics and other medications are frequently combined with hydrogel dressings in clinical practice, although these medications are easily hindered by the hostile environment. In this case, scientists have created responsive-hydrogel dressings based on the microenvironment features of diabetic wounds (such as high glucose and low pH) or combined with external stimuli (such as light or magnetic field) to achieve controllable drug release, gel degradation, and microenvironment improvements in order to overcome these clinical issues. These responsive-hydrogel dressings are anticipated to play a significant role in diabetic therapeutic wound dressings. Here, we review recent advances on responsive-hydrogel dressings towards diabetic wound healing, with focus on hydrogel structure design, the principle of responsiveness, and the behavior of degradation. Last but not least, the advantages and limitations of these responsive-hydrogels in clinical applications will also be discussed. We hope that this review will contribute to furthering progress on hydrogels as an improved dressing for diabetic wound healing and practical clinical application.

Preparation of metal-organic framework combined with Portulaca oleracea L. extract electrostatically spun nanofiber membranes delayed release wound dressing

In this study, we prepared a polyacrylonitrile (PAN) composite nanofiber membrane comprising Portulaca oleracea L. extract (POE) and a zinc-based metal-organic framework (MOF) by an in situ growth method as a potentially new type of wound dressing with a slow drug-release effect, to solve the problem of the burst release of drugs in wound dressings. The effects of the MOF and POE doping on the nanofiber membranes were examined using scanning electron microscopy (SEM) and FTIR spectroscopy. SEM analysis revealed the dense and uniform attachment of MOF particles to the surface of the nanofiber membrane, while FTIR spectroscopy confirmed the successful fusion of MOF and POE. Furthermore, investigations into the water contact angle and swelling property demonstrated that the incorporation of the MOF and POE enhanced the hydrophilicity of the material. The results of the in vitro release test showed that the cumulative release rate for PAN/MOF/POE60 decreased from 66.5 ± 2.34% to 32.18 ± 1.31% in the initial 4 h and from 90.54 ± 0.79% to 65.92 ± 1.95% in 72 h compared to PAN/POE, indicating a slowing down of the drug release. In addition, the antimicrobial properties of the fiber membranes were evaluated by the disc diffusion method, and it was evident that the PAN/MOF/POE nanofibers exhibited strong inhibition against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The antioxidant properties of the nanofiber membranes loaded with POE were further validated through the DPPH radical scavenging test. These findings highlight the potential application of the developed nanofiber membranes in wound dressings, offering controlled and sustained drug-release capabilities.

Preparation and Characterization of Polycaprolactone (PCL) Antimicrobial Wound Dressing Loaded with Pomegranate Peel Extract

In recent years, medicinal plant extracts have received remarkable attention due to their wound-healing properties. In this study, polycaprolactone (PCL) electrospun nanofiber membranes incorporated with different concentrations of pomegranate peel extract (PPE) were prepared. The results of the SEM and FTIR experiments demonstrated that the morphology of nanofiber is smooth, fine, and bead-free, and the PPE was well introduced into the nanofiber membranes. Moreover, the outcomes of the mechanical property tests demonstrated that the nanofiber membrane made of PCL and loaded with PPE exhibited remarkable mechanical characteristics, indicating that it could fulfill the essential mechanical requisites for wound dressings. The findings of the in vitro drug release investigations indicated that PPE was instantly released within 20 h and subsequently released gradually over an extended period by the composite nanofiber membranes. Meanwhile, the DPPH radical scavenging test confirmed that the nanofiber membranes loaded with PPE exhibited significant antioxidant properties. Antimicrobial experiments showed higher PPE loading, and the nanofiber membranes showed higher antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans. The results of the cellular experiments showed that the composite nanofiber membranes were nontoxic and promoted the proliferation of L929 cells. In summary, electrospun nanofiber membranes loaded with PPE can be used as a wound dressing.

Principles of extramural health care for chronic wounds in China

Development of extramural health care for chronic wounds is still in its infancy in China, and thus it is urgent and vital to establish a correct concept and practicable principles. The authors reviewed recent domestic and international literature and summarized the following treatment procedures and principles for extramural health care of chronic wounds. (1) The patient needs to do self-assessment of the wound by using available simple methods; (2) The patient consult with professional physicians or nurses on wound care to define the severity and etiology of the non-healing wound; (3) Professionals evaluate the existing treatment strategies; (4) Etiological treatments are given by professionals; (5) Patients buy needed dressings via the more convenient ways from pharmacies, e-commerce platform or others; (6) Professionals provide a standardized and reasonable therapeutic plan based on the patient's wound conditions; (7) Both professionals and the patient pay attention to complications to prevent adverse outcomes; (8) Professionals strengthen the public education on wound care and integrated rehabilitation. This review expected to provide new perspectives on the therapeutic strategies for chronic wounds in an extramural setting.

Insights into the Role of Natural Polysaccharide-Based Hydrogel Wound Dressings in Biomedical Applications

Acute skin damage caused by burns or cuts occurs frequently in people's daily lives. Such wounds are difficult to heal normally and have persistent inflammation. Wound dressings not only improve the speed of wound healing, but also protect and cover the wound well. Hydrogels have the characteristics of good flexibility, high water content, and good biocompatibility, and are widely used in biomedicine and other fields. Common hydrogels are mainly natural hydrogels and synthetic hydrogels. Hydrogels cross-linked using different raw materials and different methods have different performance characteristics. Natural hydrogels prepared using polysaccharides are simple to obtain and have good biocompatibility, but are inferior to synthetic hydrogels in terms of mechanical properties and stability, and a single polysaccharide hydrogel cannot meet the component requirements for wound healing. Therefore, functional composite hydrogels with high mechanical properties, high biocompatibility, and high antibacterial properties are the current research hotspots. In this review, several common polysaccharides for hydrogel synthesis and the synthesis methods of polysaccharide hydrogels are introduced, and functional composite hydrogel dressings from recent years are classified. It is hoped that this can provide useful references for relevant research in this field.

Evaluation of the Performance of a ZnO-Nanoparticle-Coated Hydrocolloid Patch in Wound Healing

Hydrocolloid dressings are an important method for accelerating wound healing. A combination of a hydrocolloid and nanoparticles (NPs), such as gold (Au), improves the wound healing rate, but Au-NPs are expensive and unable to block ultraviolet (UV) light. Herein, we combined zinc oxide nanoparticles (ZnO-NPs) with hydrocolloids for a less expensive and more effective UV-blocking treatment of wounds. Using Sprague–Dawley rat models, we showed that, during 10-day treatment, a hydrocolloid patch covered with ZnO-NPs (ZnO-NPs-HC) macroscopically and microscopically stimulated the wound healing rate and improved wound healing in the inflammation phase as shown by reducing of pro-inflammatory cytokines (CD68, IL-8, TNF-α, MCP-1, IL-6, IL-1β, and M1) up to 50%. The results from the in vitro models (RAW264.7 cells) also supported these in vivo results: ZnO-NPs-HCs improved wound healing in the inflammation phase by expressing a similar level of pro-inflammatory mediators (TNF-α and IL-6) as the negative control group. ZnO-NPs-HCs also encouraged the proliferation phase of the healing process, which was displayed by increasing expression of fibroblast biomarkers (α-SMA, TGF-β3, vimentin, collagen, and M2) up to 60%. This study provides a comprehensive analysis of wound healing by measuring the biomarkers in each phase and suggests a cheaper method for wound dressing.

Chitosan/PEO nanofibers containing Calendula officinalis extract: Preparation, characterization, in vitro and in vivo evaluation for wound healing applications

Wound healing is a complex pathophysiological process, highlighting the importance of effective and thorough wound care along with the prevention of wound infection, a major barrier that can slow down or even disrupt the healing process. To date, there are plenty of herbal plants well known and historically supernatural, showing profound wound healing effects. Application of such herbal extracts/ingredients in electrospun nanofiber platforms has shown promising outcomes in improving wound healing process. Based on these facts, we loaded Calendula officinalis extract (CO) in chitosan/polyethylene oxide scaffolds (CS/PEO) by electrospinning. Using SEM, morphology of electrospun scaffolds showed a narrow range of fiber diameter, around 143--252 nm, with uniform and bead-free appearance. FT-IR spectroscopy confirmed the presence of CO extract in nanofibrous scaffolds. Of importance, incorporation of CO extract improved mechanical properties of CS/PEO nanofibers. A 1602 cP reduction in viscosity and a 0.892 ms/cm increase in the conductivity of the solution was observed after addition of the CO extract. CO extract showed strong antibacterial properties with 96% and 94% reduction in Gram positive and Gram negative bacteria, respectively. In vitro studies with fibroblast cells confirmed enhanced proliferation, growth and attachment of the cells. The in vivo and histological analysis of rat wounds, revealed excellent wound healing ability of CS/PEO/CO dressings (87.5 % wound closure after 14 days) via improving collagen synthesis, re-epithelization and remodeling of the tissue. In sum, our findings show that CS/PEO/CO scaffolds can be used as a promising dressing for the treatment of skin wounds.

Using a modified Delphi methodology to gain consensus on the use of dressings in chronic wounds management

OBJECTIVE

Managing chronic wounds is associated with a burden to patients, caregivers, health services and society and there is a lack of clarity regarding the role of dressings in improving outcomes. This study aimed to provide understanding on a range of topics, including: the definition of chronicity in wounds, the burden of illness, clinical outcomes of reducing healing time and the impact of early interventions on clinical and economic outcomes and the role of matrix metalloproteinases (MMPs) in wound healing.

METHOD

A systematic review of the literature was carried out on the role of dressings in diabetic foot ulcer (DFU), and venous leg ulcer (VLU) management strategies, their effectiveness, associated resource use/cost, and quality of life (QoL) impact on patients. From this evidence-base statements were written regarding chronicity in wounds, burden of illness, healing time, and the role of MMPs, early interventions and dressings. A modified Delphi methodology involving two iterations of email questionnaires followed by a face-to-face meeting was used to validate the statements, in order to arrive at a consensus for each. Clinical experts were selected, representing nurses, surgeons, podiatrists, academics, and policy experts.

RESULTS

In the first round, 38/47 statements reached or exceeded the consensus threshold of 80% and none were rejected. According to the protocol, any statement not confirmed or rejected had to be modified using the comments from participants and resubmitted. In the second round, 5/9 remaining statements were confirmed and none rejected, leaving 4 to discuss at the meeting. All final statements were confirmed with at least 80% consensus.

CONCLUSION

This modified Delphi panel sought to gain clarity from clinical experts surrounding the use of dressings in the management of chronic wounds. A full consensus statement was developed to help clinicians and policy makers improve the management of patients with these conditions.

Therapeutic compression materials and wound dressings for chronic venous insufficiency: A comprehensive review

Chronic venous insufficiency (CVI) is a common disorder worldwide. Related pathophysiological mechanisms reportedly involve venous pooling and reduced venous return, leading to heaviness, aching, itchiness, tiredness, varicosities, pigmentation, and even lower limb ulceration. Approaches adopted to manage CVI at various stages of clinical-etiology-anatomy-pathophysiology include compression therapy, pharmacological treatment, ultrasound treatment, surgery, electrical or wireless microcurrent stimulation, and pulsed electromagnetic treatment. Among these, polymer-based therapeutic compression materials and wound dressings play increasingly key roles in treating all stages of CVI because of their unique physical, mechanical, chemical, and biological functions. However, the characteristics, working mechanisms, and effectiveness of these CVI treatment materials are not comprehensively understood. The present systematic review examines the structures, properties, types, and applications of various polymer-based compression materials and wound dressings used in prophylaxis and treatment of CVI. Existing problems, limitations, and future trends of CVI treatment materials are also discussed. This review could contribute to the design and application of new functional polymer materials and dressings to enhance the efficiency of CVI treatments, thereby facilitating patients' self-care ability and long-term health improvement.

Foam dressings for treating pressure injuries in patients of any age in any care setting: An abridged Cochrane systematic review

BACKGROUND

Pressure injuries are localised areas of injury to the skin and/or underlying tissues.

OBJECTIVES

To assess foam dressings compared to other dressings in healing pressure injuries.

DESIGN

Systematic review and meta-analysis DATA SOURCES: The review team searched: the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials; Ovid MEDLINE; Ovid Embase; EBSCO CINAHL Plus and the NHS Economic Evaluation Database. Authors also searched clinical trials registries and scanned reference lists for reviews, meta-analyses and health technology reports. No restrictions were applied to language, publication date or study setting.

STUDY ELIGIBILITY CRITERIA

Published or unpublished randomised controlled trials and cluster- randomised controlled trials that examined the clinical or cost effectiveness of foam dressings for healing pressure injuries.

PARTICIPANTS

Patients of any age with a pressure injury of Stage II or above in any care setting.

INTERVENTIONS

Use of any foam wound dressing for treating Stage II pressure injuries or above.

STUDY APPRAISAL AND SYNTHESIS METHODS

Full-text were assessed for eligibility using a priori criteria by two authors. Risk of bias was assessed using the Grading of Recommendations, Assessment, Development and Evaluation criteria, and Consolidated Health Economic Evaluation Reporting Standards. Risk ratio and mean difference with 95% confidence intervals were used to measure the effect. The review team used Review Manager 5 to enter narrative and qualitative data of included studies.

RESULTS

Authors found nine studies published between 1994 and 2016 involving 483 participants with pressure injuries at Stage II or above. Included studies compared foam dressings with other types of dressings. However, it was unclear if the foam dressing affected healing (RR 1.00, 95% CI 0.78-1.28), time to complete healing (MD 5.67 days 95% CI-4.03-15.37), adverse events (RR 0.33, 95% CI 0.01-7.65), or reduction in pressure injury size (MD 0.30 cm² per day, 95% CI -0.15 to 0.75), as the certainty of the evidence was very low.

LIMITATIONS

Using the Grading of Recommendations, Assessment, Development and Evaluation criteria, the certainty and completeness of evidence was low to very low, making it difficult to draw comparisons between foam and other dressings.

CONCLUSIONS AND IMPLICATIONS

It is uncertain whether foam dressings are more clinically effective, more acceptable to users, or more cost effective compared to alternative dressings in treating pressure injuries.

Hydrogel Effects Rapid Biofilm Debridement with ex situ Contact-Kill to Eliminate Multidrug Resistant Bacteria in vivo

Multidrug resistance and the refractory character of bacterial biofilms are among the most difficult challenges in infection treatment. Current antimicrobial strategies typically are much more effective for prevention of biofilm formation than for eradication of established biofilms; these strategies also leave dead bacteria and endotoxin in the infection site, which impairs healing. We report a novel hydrogel that eradicates biofilm bacteria by non-leaching-based debridement followed by ex situ contact-killing (DESCK) away from the infection site. The debridement effect is likely due to the high water swellability and microporosity of the cross-linked network which is made from polyethylene glycol dimethacrylate tethered with a dangling polyethylenimine (PEI) star copolymer. The large pore size of the hydrogel makes the cationic pore walls highly accessible to bacteria. The hydrogel also degrades in the presence of infection cells, releasing star cationic PEI into the infection site to contact-kill bacteria remaining there. DESCK hydrogel effectively kills (>99.9% reduction) biofilms of methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Pseudomonas aeruginosa (CR-PA) and Acinetobacter baumannii in a murine excisional wound infection model. Silver-based wound dressings (controls) showed almost no killing of CR-PA and MRSA biofilms. This DESCK hydrogel greatly reduces the bioburden and inflammation and promotes wound healing. It has great potential for diverse infection treatment applications.

Foam dressings for treating pressure ulcers

BACKGROUND

Pressure ulcers, also known as pressure injuries and bed sores, are localised areas of injury to the skin or underlying tissues, or both. Dressings made from a variety of materials, including foam, are used to treat pressure ulcers. An evidence-based overview of dressings for pressure ulcers is needed to enable informed decision-making on dressing use. This review is part of a suite of Cochrane Reviews investigating the use of dressings in the treatment of pressure ulcers. Each review will focus on a particular dressing type.

OBJECTIVES

To assess the clinical and cost effectiveness of foam wound dressings for healing pressure ulcers in people with an existing pressure ulcer in any care setting.

SEARCH METHODS

In February 2017 we searched: the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE (including In-Process & Other Non-Indexed Citations); Ovid Embase; EBSCO CINAHL Plus and the NHS Economic Evaluation Database (NHS EED). We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

Published or unpublished randomised controlled trials (RCTs) and cluster-RCTs, that compared the clinical and cost effectiveness of foam wound dressings for healing pressure ulcers (Category/Stage II or above).

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias and data extraction. A third reviewer resolved discrepancies between the review authors.

MAIN RESULTS

We included nine trials with a total of 483 participants, all of whom were adults (59 years or older) with an existing pressure ulcer Category/Stage II or above. All trials had two arms, which compared foam dressings with other dressings for treating pressure ulcers.The certainty of evidence ranged from low to very low due to various combinations of selection, performance, attrition, detection and reporting bias, and imprecision due to small sample sizes and wide confidence intervals. We had very little confidence in the estimate of effect of included studies. Where a foam dressing was compared with another foam dressing, we established that the true effect was likely to be substantially less than the study's estimated effect.We present data for four comparisons.One trial compared a silicone foam dressing with another (hydropolymer) foam dressing (38 participants), with an eight-week (short-term) follow-up. It was uncertain whether alternate types of foam dressing affected the incidence of healed pressure ulcers (RR 0.89, 95% CI 0.45 to 1.75) or adverse events (RR 0.37, 95% CI 0.04 to 3.25), as the certainty of evidence was very low, downgraded for serious limitations in study design and very serious imprecision.Four trials with a median sample size of 20 participants (230 participants), compared foam dressings with hydrocolloid dressings for eight weeks or less (short-term). It was uncertain whether foam dressings affected the probability of healing in comparison to hydrocolloid dressings over a short follow-up period in three trials (RR 0.85, 95% CI 0.54 to 1.34), very low-certainty evidence, downgraded for very serious study limitations and serious imprecision. It was uncertain if there was a difference in risk of adverse events between groups (RR 0.88, 95% CI 0.37 to 2.11), very low-certainty evidence, downgraded for serious study limitations and very serious imprecision. Reduction in ulcer size, patient satisfaction/acceptability, pain and cost effectiveness data were also reported but we assessed the evidence as being of very low certainty.One trial (34 participants), compared foam and hydrogel dressings over an eight-week (short-term) follow-up. It was uncertain if the foam dressing affected the probability of healing (RR 1.00, 95% CI 0.78 to 1.28), time to complete healing (MD 5.67 days 95% CI -4.03 to 15.37), adverse events (RR 0.33, 95% CI 0.01 to 7.65) or reduction in ulcer size (MD 0.30 cm² per day, 95% CI -0.15 to 0.75), as the certainty of the evidence was very low, downgraded for serious study limitations and very serious imprecision.The remaining three trials (181 participants) compared foam with basic wound contact dressings. Follow-up times ranged from short-term (8 weeks or less) to medium-term (8 to 24 weeks). It was uncertain whether foam dressings affected the probability of healing compared with basic wound contact dressings, in the short term (RR 1.33, 95% CI 0.62 to 2.88) or medium term (RR 1.17, 95% CI 0.79 to 1.72), or affected time to complete healing in the medium term (MD -35.80 days, 95% CI -56.77 to -14.83), or adverse events in the medium term (RR 0.58, 95% CI 0.33 to 1.05). This was due to the very low-certainty evidence, downgraded for serious to very serious study limitations and imprecision. Reduction in ulcer size, patient satisfaction/acceptability, pain and cost effectiveness data were also reported but again, we assessed the evidence as being of very low certainty.None of the included trials reported quality of life or pressure ulcer recurrence.

AUTHORS' CONCLUSIONS

It is uncertain whether foam dressings are more clinically effective, more acceptable to users, or more cost effective compared to alternative dressings in treating pressure ulcers. It was difficult to make accurate comparisons between foam dressings and other dressings due to the lack of data on reduction of wound size, complete wound healing, treatment costs, or insufficient time-frames. Quality of life and patient (or carer) acceptability/satisfaction associated with foam dressings were not systematically measured in any of the included studies. We assessed the certainty of the evidence in the included trials as low to very low. Clinicians need to carefully consider the lack of robust evidence in relation to the clinical and cost-effectiveness of foam dressings for treating pressure ulcers when making treatment decisions, particularly when considering the wound management properties that may be offered by each dressing type and the care context.

Dressings and topical agents for treating pressure ulcers

BACKGROUND

Pressure ulcers, also known as bedsores, decubitus ulcers and pressure injuries, are localised areas of injury to the skin or the underlying tissue, or both. Dressings are widely used to treat pressure ulcers and promote healing, and there are many options to choose from including alginate, hydrocolloid and protease-modulating dressings. Topical agents have also been used as alternatives to dressings in order to promote healing.A clear and current overview of all the evidence is required to facilitate decision-making regarding the use of dressings or topical agents for the treatment of pressure ulcers. Such a review would ideally help people with pressure ulcers and health professionals assess the best treatment options. This review is a network meta-analysis (NMA) which assesses the probability of complete ulcer healing associated with alternative dressings and topical agents.

OBJECTIVES

To assess the effects of dressings and topical agents for healing pressure ulcers in any care setting. We aimed to examine this evidence base as a whole, determining probabilities that each treatment is the best, with full assessment of uncertainty and evidence quality.

SEARCH METHODS

In July 2016 we searched the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); Ovid Embase and EBSCO CINAHL Plus. We also searched clinical trials registries for ongoing and unpublished studies, and scanned reference lists of relevant included studies as well as reviews, meta-analyses, guidelines and health technology reports to identify additional studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

Published or unpublished randomised controlled trials (RCTs) comparing the effects of at least one of the following interventions with any other intervention in the treatment of pressure ulcers (Stage 2 or above): any dressing, or any topical agent applied directly to an open pressure ulcer and left in situ. We excluded from this review dressings attached to external devices such as negative pressure wound therapies, skin grafts, growth factor treatments, platelet gels and larval therapy.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, risk of bias assessment and data extraction. We conducted network meta-analysis using frequentist mega-regression methods for the efficacy outcome, probability of complete healing. We modelled the relative effectiveness of any two treatments as a function of each treatment relative to the reference treatment (saline gauze). We assumed that treatment effects were similar within dressings classes (e.g. hydrocolloid, foam). We present estimates of effect with their 95% confidence intervals for individual treatments compared with every other, and we report ranking probabilities for each intervention (probability of being the best, second best, etc treatment). We assessed the certainty (quality) of the body of evidence using GRADE for each network comparison and for the network as whole.

MAIN RESULTS

We included 51 studies (2947 participants) in this review and carried out NMA in a network of linked interventions for the sole outcome of probability of complete healing. The network included 21 different interventions (13 dressings, 6 topical agents and 2 supplementary linking interventions) and was informed by 39 studies in 2127 participants, of whom 783 had completely healed wounds.We judged the network to be sparse: overall, there were relatively few participants, with few events, both for the number of interventions and the number of mixed treatment contrasts; most studies were small or very small. The consequence of this sparseness is high imprecision in the evidence, and this, coupled with the (mainly) high risk of bias in the studies informing the network, means that we judged the vast majority of the evidence to be of low or very low certainty. We have no confidence in the findings regarding the rank order of interventions in this review (very low-certainty evidence), but we report here a summary of results for some comparisons of interventions compared with saline gauze. We present here only the findings from evidence which we did not consider to be very low certainty, but these reported results should still be interpreted in the context of the very low certainty of the network as a whole.It is not clear whether regimens involving protease-modulating dressings increase the probability of pressure ulcer healing compared with saline gauze (risk ratio (RR) 1.65, 95% confidence interval (CI) 0.92 to 2.94) (moderate-certainty evidence: low risk of bias, downgraded for imprecision). This risk ratio of 1.65 corresponds to an absolute difference of 102 more people healed with protease modulating dressings per 1000 people treated than with saline gauze alone (95% CI 13 fewer to 302 more). It is unclear whether the following interventions increase the probability of healing compared with saline gauze (low-certainty evidence): collagenase ointment (RR 2.12, 95% CI 1.06 to 4.22); foam dressings (RR 1.52, 95% CI 1.03 to 2.26); basic wound contact dressings (RR 1.30, 95% CI 0.65 to 2.58) and polyvinylpyrrolidone plus zinc oxide (RR 1.31, 95% CI 0.37 to 4.62); the latter two interventions both had confidence intervals consistent with both a clinically important benefit and a clinically important harm, and the former two interventions each had high risk of bias as well as imprecision.

AUTHORS' CONCLUSIONS

A network meta-analysis (NMA) of data from 39 studies (evaluating 21 dressings and topical agents for pressure ulcers) is sparse and the evidence is of low or very low certainty (due mainly to risk of bias and imprecision). Consequently we are unable to determine which dressings or topical agents are the most likely to heal pressure ulcers, and it is generally unclear whether the treatments examined are more effective than saline gauze.More research is needed to determine whether particular dressings or topical agents improve the probability of healing of pressure ulcers. The NMA is uninformative regarding which interventions might best be included in a large trial, and it may be that research is directed towards prevention, leaving clinicians to decide which treatment to use on the basis of wound symptoms, clinical experience, patient preference and cost.