Wound shape geometry measurements correlate to eventual wound healing

Wound geometry measurements have long been associated with wound-healing outcomes but there is little published evidence to support this. We studied serial wound tracings of 338 venous leg ulcers (VLUs) that had been followed during a controlled, prospective, randomized pivotal trial of two topical wound treatments, to determine whether the relationship between wound surface area and wound perimeter planimetry measurements, as well as the qualitative assessment of wound shape, could be correlated to wound-healing outcomes. VLUs that transitioned to a more convex wound shape, and maintained a linear relationship between their wound margin size and wound surface area size, had faster healing rates and were more likely to completely heal by 12 weeks (odds ratio=4.84, p =0.001). VLUs that initially presented with isolated areas of epithelium within the wound margins, large concavities, or were segmented into multiple ulcers typically had a poorer linear correlation between their margins and their surface area. Only 18 out of 134 (13%) VLUs with a linear r ²<0.80 eventually reached full wound closure, vs. 43% (102 of 270) of the remaining wounds with an r ²≥0.80 (Fisher's exact p <0.001). We believe our results show that the proportional relationship between one-dimensional perimeter and area measurements accurately correlates to the healing progress of the wound. Wounds that do not correlate to this linear relationship (concave geometries or multiple islands of healing) may be physiologically different than wounds that have good linear correlation, which we concluded through the analysis of wound acetate tracings.     

The role of surgical debridement in healing of diabetic foot ulcers

A critical question in the treatment of chronic wounds is whether and when debridement is needed. The three most common chronic wounds are the diabetic foot ulcer (DFU), the venous leg ulcer, and the pressure or decubitus ulcer. Surgical debridement, aimed at removing necrotic, devitalized wound bed and wound edge tissue that inhibits healing, is a longstanding standard of care for the treatment of chronic, nonhealing wounds. Debridement encourages healing by converting a chronic nonhealing wound environment into a more responsive acute healing environment. While the rationale for debridement seems logical, the evidence to support its use in enhancing healing is scarce. Currently, there is more evidence in the literature for debridement for DFUs than for venous ulcers and pressure ulcers; however, the studies on which clinicians have based their rationale for debridement in DFUs possess methodologic flaws, small sample sizes, and bias. Thus, further studies are needed to develop clinical evidence for its inclusion in treatment protocols for chronic wounds. Here, the authors review the scientific evidence for debridement of DFUs, the rationale for debridement of DFUs, and the insufficient data supporting debridement for venous ulcers and pressure ulcers.     

A multicentre prospective randomised controlled comparative parallel study of dehydrated human umbilical cord (EpiCord) allograft for the treatment of diabetic foot ulcers

The aim of this study was to determine the safety and effectiveness of dehydrated human umbilical cord allograft (EpiCord) compared with alginate wound dressings for the treatment of chronic, non‐healing diabetic foot ulcers (DFU). A multicentre, randomised, controlled, clinical trial was conducted at 11 centres in the United States. Individuals with a confirmed diagnosis of Type 1 or Type 2 diabetes presenting with a 1 to 15 cm² ulcer located below the ankle that had been persisting for at least 30 days were eligible for the 14‐day study run‐in phase. After 14 days of weekly debridement, moist wound therapy, and off‐loading, those with ≤30% wound area reduction post‐debridement (n = 155) were randomised in a 2:1 ratio to receive a weekly application of EpiCord (n = 101) or standardised therapy with alginate wound dressing, non‐adherent silicone dressing, absorbent non‐adhesive hydropolymer secondary dressing, and gauze bandage roll (n = 54). All wounds continued to have appropriate off‐loading during the treatment phase of the study. Study visits were conducted for 12 weeks. At each weekly visit, the DFU was cleaned and debrided as necessary, with the wound photographed pre‐ and post‐debridement and measured before the application of treatment group‐specific dressings. A follow‐up visit was performed at week 16. The primary study end point was the percentage of complete closure of the study ulcer within 12 weeks, as assessed by Silhouette camera. Data for randomised subjects meeting study inclusion criteria were included in an intent‐to‐treat (ITT) analysis. Additional analysis was conducted on a group of subjects (n = 134) who completed the study per protocol (PP) (EpiCord, n = 86, alginate, n = 48) and for those subjects receiving adequate debridement (EpiCord, n = 67, alginate, n = 40). ITT analysis showed that DFUs treated with EpiCord were more likely to heal within 12 weeks than those receiving alginate dressings, 71 of 101 (70%) vs 26 of 54 (48%) for EpiCord and alginate dressings, respectively, P = 0.0089. Healing rates at 12 weeks for subjects treated PP were 70 of 86 (81%) for EpiCord‐treated and 26 of 48 (54%) for alginate‐treated DFUs, P = 0.0013. For those DFUs that received adequate debridement (n = 107, ITT population), 64 of 67 (96%) of the EpiCord‐treated ulcers healed completely within 12 weeks, compared with 26 of 40 (65%) of adequately debrided alginate‐treated ulcers, P < 0.0001. Seventy‐five subjects experienced at least one adverse event, with a total of 160 adverse events recorded. There were no adverse events related to either EpiCord or alginate dressings. These results demonstrate the safety and efficacy of EpiCord as a treatment for non‐healing DFUs.     

A prospective,randomized, controlled clinical trial on the efficacy of a single‐use negative pressure wound therapy system,compared to traditional negative pressure wound therapy in the treatment of chronic ulcers of the lower extremities

Multicenter, phase‐4, randomized, comparative‐efficacy study in patients with VLUs or DFUs comparing for noninferiority the percentage change in target ulcer dimensions (area, depth, and volume) a single‐use negative pressure wound therapy (s‐NPWT) system versus traditional NPWT (t‐NPWT) over a 12‐week treatment period or up to confirmed healing. Baseline values were taken at the randomization visit. Randomized by wound type and size, 164 patients with non‐infected DFUs and VLUs were included. The ITT population was composed of 161 patients (101 with VLUs, 60 with DFUs) and 115 patients completed follow‐up (64 in the s‐NPWT group and 51 in the t‐NPWT group) (PP population). The average age for all patients was 61.5 years, 36.6% were women, and treatment groups were statistically similar at baseline. Primary endpoint analyses on wound area reduction demonstrated statistically significant reduction in favor of s‐NPWT (p = 0.003) for the PP population and for the ITT population (p < 0.001). Changes in wound depth (p = 0.018) and volume (p = 0.013) were also better with s‐NPWT. Faster wound closure was observed with s‐NPWT (Cox Proportional Hazards ratio (0.493 (0.273, 0.891); p = 0.019) in the ITT population. Wound closure occurred in 45% of patients in the s‐NPWT group vs. 22.2% of patients in the t‐NPWT group (p = 0.002). Median estimate of the time to wound closure was 77 days for s‐NPWT. No estimate could be provided for t‐NPWT due to the low number of patients achieving wound closure. Device‐related AEs were more frequent in the t‐NPWT group (41 AEs from 29 patients) than in the s‐NPWT group (16 AEs from 12 patients). The s‐NPWT system met noninferiority and achieved statistical superiority vs. t‐NPWT in terms of wound progression toward healing over the treatment period. When NPWT is being considered for the management of challenging VLUs and DFUs, s‐NPWT should be considered a first choice over other types of NPWT.     

Debridement performance index and its correlation with complete closure of diabetic foot ulcers

In recent years there has been wider acceptance of aggressive surgical debridement as a means to accelerate closure of diabetic foot ulcers. In a clinical trial by Steed et al.1 involving the use of a topically applied growth factor, thorough surgical debridement of surrounding callus, necrotic ulcer bed, and undermined ulcers' edges was associated with greater incidence of healing and effectiveness of the therapeutic agent. However, at present there is no established way to judge the appropriate extent of debridement and its performance. Here we describe a scoring system to assess whether debridement has been performed adequately. Our scoring system consists of the following three categories: debridement of a) callus; b) ulcer's edge undermining; and c) wound bed necrotic tissue. We assigned a score of 0-2 to each of these categories using the following criteria: 0 = debridement needed but not done, 1 = debridement needed and done, and 2 = debridement not needed. These three scores are then added to give a total ranging from 0 to 6, with the highest number being the optimal score. This instrument, the Debridement Performance Index, evaluates both the adequacy of debridement and whether the ulcer has been or is being properly debrided. To initiate the validation of this scoring system and determine its predictive value for wound closure by week 12, we applied it to 143 patients with diabetic foot ulcers who had been treated in a clinical trial involving either standard therapy (n = 65) or the application of a bioengineered skin construct (n = 78). We blindly evaluated sequential digital photographs of each diabetic foot ulcer and applied the Debridement Performance Index score at day 0, before initiation of either treatment. We found that the lower the baseline Debridement Performance Index the lower the incidence of ultimate wound closure by week 12 ( p = 0.0276). Patients with a Debridement Performance Index between 3 and 6 were 2.4 times more likely to heal than those with a score of 0-2. After controlling for treatment, the Debridement Performance Index was found to be an independent predictor of wound closure (odds ratio = 2.4 95% confidence interval = 1.0-5.6). In conclusion, this novel scoring system for debridement performance appears to be very promising as a predictive tool for determining outcome in clinical trials and, most likely, in clinical practice.     

A prospective,randomised, controlled,multicentre clinical trial examining healing rates,safety and cost to closure of an acellular reticular allogenic human dermis versus standard of care in the treatment of chronic diabetic foot ulcers

Acellular dermal matrices can successfully heal wounds. This study's goal was to compare clinical outcomes of a novel, open‐structure human reticular acellular dermis matrix (HR‐ADM) to facilitate wound closure in non‐healing diabetic foot ulcers (DFUs) versus DFUs treated with standard of care (SOC). Following a 2‐week screening period in which DFUs were treated with offloading and moist wound care, patients were randomised to either SOC alone or HR‐ADM plus SOC applied weekly for up to 12 weeks. At 6 weeks, the primary outcome time, 65% of the HR‐ADM‐treated DFUs healed (13/20) compared with 5% (1/20) of DFUs that received SOC alone. At 12 weeks, the proportions of DFUs healed were 80% and 20%, respectively. Mean time to heal within 12 weeks was 40 days for the HR‐ADM group compared with 77 days for the SOC group. There was no incidence of increased adverse or serious adverse events between groups or any adverse events related to the graft. Mean and median graft costs to closure per healed wound in the HR‐ADM group were $1475 and $963, respectively. Weekly application of HR‐ADM is an effective intervention for promoting closure of non‐healing DFUs.     

A retrospective clinical study of 188 consecutive patients to examine the effectiveness of a biologically active cryopreserved human skin allograft (TheraSkin®) on the treatment of diabetic foot ulcers and venous leg ulcers

A biologically active human skin allograft, currently distributed under the brand name TheraSkin(?), was examined for safety and efficacy in the treatment of venous leg ulcers (VLUs) and diabetic foot ulcers (DFUs). The objective was to determine if TheraSkin could serve as a safe and effective alternative to bioengineered skin substitutes such as Apligraf(?) and Dermagraft(?). The authors conducted a retrospective study of 214 consecutive patients seen at the Inova Wound Center (Mt Vernon, Virginia), with either a DFU or a VLU. After excluding patients who did not meet the study criteria, the final eligible cohort consisted of 188 subjects, with 134 VLUs and 54 DFUs. Multivariate logistic regression was used to evaluate the relationship between baseline wound size and the proportion of healed wounds after 12 and 20 weeks from initial allograft application. The authors found that by the 12th week, DFUs closed 60.38% of the time and VLUs closed 60.77% of the time. After 20 weeks, the number of closed DFUs increased to 74.1% and the number of VLUs increased to 74.6%. The mean wound size in the DFU group was 6.2 cm(2) (±11.8) and 11.8 cm(2) (±22.5) in the VLU group. The mean number of TheraSkin allografts required ranged from 1 to 8, with an average of 2.03 (±1.47) at the 12-week point and an average of 3.23 (±2.77) at the 20-week point. Multivariate logistic regression was used to calculate the odds of wound healing by week 12 and week 20 in each group. The authors also analyzed adverse events and found TheraSkin to be noncontributory to any adverse events, verifying the safety of TheraSkin in this study population. In this study, TheraSkin has been shown to be highly effective for the treatment of both VLUs and DFUs with an acceptable safety profile.     

A pilot multi‐centre prospective randomised controlled trial of RECELL for the treatment of venous leg ulcers

Venous leg ulcers (VLUs) have a significant impact on approximately 3% of the adult population worldwide, with a mean NHS wound care cost of £7600 per VLU over 12 months. The standard care for VLUs is compression therapy, with a significant number of ulcers failing to heal with this treatment, especially with wound size being a risk factor for non‐healing. This multicentre, prospective, randomised trial evaluated the safety and effectiveness of autologous skin cell suspension (ASCS) combined with compression therapy compared with standard compression alone (Control) for the treatment of VLUs. Incidence of complete wound closure at 14 weeks, donor site closure, pain, Health‐Related Quality of Life (HRQoL), satisfaction, and safety were assessed in 52 patients. At Week 14, VLUs treated with ASCS + compression had a statistically greater decrease in ulcer area compared with the Control (8.94 cm² versus 1.23 cm², P = .0143). This finding was largely driven by ulcers >10 to 80 cm² in size, as these ulcers had a higher mean percentage of reepithelialization at 14 weeks (ASCS + compression: 69.97% and Control: 11.07%, P = .0480). Additionally, subjects treated with ASCS + compression experienced a decrease in pain and an increase in HRQoL compared with the Control. This study indicates that application of ASCS + compression accelerates healing in large venous ulcers.     

The role of surgical debridement in healing of diabetic foot ulcers

An estimated 15% of patients with diabetes mellitus will develop a foot ulcer during their lifetime. Debridement is included in multiple guidelines and algorithms for the care of patients with diabetic neuropathic foot ulcers, and it has long been considered an essential step in the protocol for treating diabetic foot ulcers. In addition to altering the environment of the chronic wound, debridement is a technique aimed at removing nonviable and necrotic tissue, thought to be detrimental to healing. This is accomplished by removing abnormal wound bed and wound edge tissue, such as hyperkeratotic epidermis (callus) and necrotic dermal tissue, foreign debris, and bacteria elements known to have an inhibitory effect on wound healing. While the rationale for surgical debridement seems logical, the evidence for its role in enhancing healing is deficient. In this paper, we systematically review five published clinical trials, which met the criteria and investigated surgical debridement of diabetic foot ulcers to enhance healing. Most existing studies are not randomized clinical trials optimized to test the relationship between debridement of diabetic foot ulcers and wound healing. Therefore, a focused, well‐designed study is needed to elucidate the effect of surgical debridement on the healing status of chronic wounds.     

Enzymatic wound debridement

BACKGROUND: Clinical experience and existing research strongly support debridement as a necessary component of wound bed preparation when slough or eschar is present. Multiple techniques are available, but the indications for each technique and their efficacy are not clearly established. There is little evidence to guide the clinician in the selection of a safe, effective debridement method for the patient with a chronic wound. OBJECTIVES: We sought to identify evidence related to the efficacy of enzymatic debriding agents collagenase and papain-urea in the removal of necrotic tissue from the wound bed and its impact on wound healing. SEARCH STRATEGY: A systematic review of electronic databases was undertaken using key words: (1) debridement, (2) enzymatic debridement, (3) collagenases, (4) papain, (5) urea, and (6) papain-urea. All prospective and retrospective studies that compared enzymatic debridement using collagenase or papain-urea (with and without chlorophyllin) on pressure ulcers, leg ulcers, or burn wounds were included in the review. All studies that met inclusion criteria and were published between January 1960 and February 2008 were included. RESULTS: Collagenase ointment is more effective than placebo (inactivated ointment or petrolatum ointment) for debridement of necrotic tissue from pressure ulcers, leg ulcers, and partial-thickness burn wounds. Limited evidence suggests that a papain-urea-based ointment removes necrotic material from pressure ulcers more rapidly than collagenase ointment, but progress toward wound healing appears to be equivocal. Limited evidence suggests that treatment of partial-thickness burn wounds in children with collagenase ointment may require an equivocal time to treatment with surgical excision and that combination treatment may reduce the need for surgical excision. Insufficient evidence was found to determine whether collagenase ointment removes necrotic tissue from leg ulcers more or less rapidly than autolytic debridement enhanced by a polyacrylate dressing. IMPLICATIONS FOR PRACTICE: Enzymatic debriding agents are an effective alternative for removing necrotic material from pressure ulcers, leg ulcers, and partial-thickness wounds. They may be used to debride both adherent slough and eschar. Enzymatic agents may be used as the primary technique for debridement in certain cases, especially when alternative methods such as surgical or conservative sharp wound debridement (CSWD) are not feasible owing to bleeding disorders or other considerations. Many clinicians will select enzymes when CSWD is not an option. Clinical experience strongly suggests that combined therapy, such as initial surgical debridement followed by serial debridement using an enzymatic agent or enzymatic debridement along with serial CSWD, is effective for many patients with chronic, indolent, or nonhealing wounds.     

A prospective randomised controlled clinical trial comparing hydrosurgery debridement with conventional surgical debridement in lower extremity ulcers

Debridement of devitalised tissue is an essential component of the effective treatment of chronic wounds. The Versajet Hydrosurgery System is a new technology that simultaneously cuts and aspirates soft tissue. In this study we compared Versajet with conventional surgical techniques in the debridement of lower extremity ulcers to assess impact on time and resources for debridement. Forty-one patients with a mean age of 68 years (range 33 to 95 years) underwent surgical debridement of a lower extremity ulcer. Operating room (OR) sessions were randomised to Versajet (n= 22) or conventional debridement (n= 19) with scalpel plus pulsed lavage. Procedure time and utilisation of consumables were recorded. Wound areas were monitored for 12 weeks. There was significant evidence (P < 0.008) of a shorter debridement time (10.8 min) using Versajet over conventional debridement (17.7 min); a mean saving of 6.9 minutes (39%). In addition, a significant reduction in use of pulsed lavage and saline (P < 0.001) was observed with Versajet. Overall, clinical efficacy of the shorter debridement procedure was similar: median time to wound closure 71 days (Versajet) vs. 74 days (conventional) (P= 0.733). We found Versajet to be quicker than conventional debridement in the debridement of lower extremity ulcers without compromising wound healing. Potential cost savings were identified from the use of VERSAJET through the shorter debridement time allowing more patients to be treated in the same operating schedule.     

Low‐grade elastic compression regimen for venous leg ulcers – an effective compromise for patients requiring daily dressing changes

Venous leg ulcers (VLUs) affect millions of patients worldwide and are a tremendous financial burden on our health care system. The hallmark of venous disease of the lower extremities is venous hypertension, and compression is the current mainstay of treatment. However, many patients are non‐compliant, partly because of the complexity of the dressings and the difficulties with application and removal. The aim of our study was to test an effective compression dressing regimen for patients with VLUs who require changing the ulcer primary dressing twice daily. We used two layers of a latex‐free tubular elastic bandage for compression. The primary endpoint of our study was increased wound‐healing rate and our secondary endpoint was complete wound closure. All active study subjects had positive healing rates at week 4 and week 8. Two subjects achieved complete wound closure by week 8. We conclude that compression with a latex‐free tubular elastic bandage can be safely used in patients with VLUs requiring frequent dressing changes. This type of compression allows for daily inspection of wounds, dressing changes at home, flexibility in the context of clinical trials, and is a compromise for patients who are intolerant to compression dressings.     

Autologous platelet‐rich gel for treatment of diabetic chronic refractory cutaneous ulcers: A prospective,randomized clinical trial

The purpose of the study is to examine the safety and effectiveness of topical autologous platelet‐rich gel (APG) application on facilitating the healing of diabetic chronic refractory cutaneous ulcers. The study was designed as a prospective, randomized controlled trial between January 1, 2007 and December 31, 2011. Eligible inpatients at the Diabetic Foot Care Center of West China Hospital, Sichuan University (China) were randomly prescribed with a 12‐week standard treatment of ulcers (the control group) or standard treatment plus topical application APG (the APG group). The wound healing grades (primary endpoint), time to complete healing, and healing velocity within 12 weeks were monitored as short‐term effectiveness measurements, while side effects were documented safety endpoints. The rates of survival and recurrence within the follow up were recorded as long‐term effectiveness endpoints. Analysis on total diabetic ulcers (DUs) (n = 117) and subgroup analysis on diabetic foot ulcers (DFUs) (n = 103) were both conducted. Standard treatment plus APG treatment was statistically more effective than standard treatment (p < 0.05 in both total DUs and subgroup of DFUs). The subjects defined as healing grade 1 were 50/59 (84.8%) in total DUs and 41/48 (85.4%) in DFUs in the APG group compared with 40/58 (69.0%) and 37/55 (67.3%) in the control group from intent to treat population. The Kaplan‐Meier time‐to‐healing were significantly different between the two groups (p < 0.05 in both total DUs and subgroup of DFUs). No side effects were identified after topical APG application. The long‐term survival and recurrence rates were comparative between groups (p > 0.05). This study shows that topical APG application plus standard treatment is safe and quite effective on diabetic chronic refractory cutaneous ulcers, compared with standard treatment.     

Diabetes is associated with an increased risk of wound complications and readmission in patients with surgically managed pressure ulcers

The effect of diabetes on postoperative outcomes following surgical management of pressure ulcers is poorly defined despite evidence showing that patients with diabetes are at increased risk for developing pressure ulcers, as well as postoperative wound complications including delayed healing and infection. This study aimed to examine the impact of diabetes on postoperative outcomes following surgical management of pressure ulcers using the American College of Surgeons National Surgical Quality Improvement Program (ACS‐NSQIP) database. In this retrospective analysis all CPT codes with ICD‐9 diagnoses of pressure ulcers were reviewed. A total of 3,274 patients who underwent surgical management of pressure ulcers were identified, of which 1,040 (31.8%) had diabetes. Overall primary outcomes showed rates of superficial and deep incisional surgical site infection (SSI) were 2.0 and 4.2%, respectively, while the rate of wound dehiscence was 2.1%. Univariate analysis of primary outcomes stratified by diabetes status showed that patients with diabetes had significantly higher rates of superficial incisional SSI (3.9 vs. 2.3%; p = 0.01), deep incisional SSI (7.0 vs. 4.3%; p = 0.001), wound dehiscence (5.2 vs. 2.7%; p < 0.001), as well as significantly higher rates of readmission (12.8 vs. 8.9%; p = 0.001). Multivariate analysis for significant outcomes between groups on univariate analysis demonstrated that diabetes was an independent risk factor for superficial incisional SSI (OR = 2.7; 95% CI: 1.59–4.62; p < 0.001), deep incisional SSI (OR = 1.85; 95% CI: 1.26–2.70; p = 0.002), wound dehiscence (OR = 4.09; 95% CI: 2.49–6.74; p < 0.001), and readmission within 30 days (OR = 1.38; 95% CI: 1.05–1.82; p = 0.02). These findings emphasize the importance of preoperative prevention, and vigilant postoperative wound care and monitoring in patients with diabetes to minimize morbidity and optimize outcomes. Future prospective studies are needed to establish causality between diabetes and these outcomes.     

The efficacy and safety of Grafix® for the treatment of chronic diabetic foot ulcers: results of a multi‐centre,controlled, randomised,blinded, clinical trial

In a randomised, controlled study, we compared the efficacy of Grafix^®, a human viable wound matrix (hVWM) (N = 50), to standard wound care (n = 47) to heal diabetic foot ulcers (DFUs). The primary endpoint was the proportion of patients with complete wound closure by 12 weeks. Secondary endpoints included the time to wound closure, adverse events and wound closure in the crossover phase. The proportion of patients who achieved complete wound closure was significantly higher in patients who received Grafix (62%) compared with controls (21%, P = 0·0001). The median time to healing was 42 days in Grafix patients compared with 69·5 days in controls (P = 0·019). There were fewer Grafix patients with adverse events (44% versus 66%, P = 0·031) and fewer Grafix patients with wound‐related infections (18% versus 36·2%, P = 0·044). Among the study subjects that healed, ulcers remained closed in 82·1% of patients (23 of 28 patients) in the Grafix group versus 70% (7 of 10 patients) in the control group (P = 0·419). Treatment with Grafix significantly improved DFU healing compared with standard wound therapy. Importantly, Grafix also reduced DFU‐related complications. The results of this well‐controlled study showed that Grafix is a safe and more effective therapy for treating DFUs than standard wound therapy.     

Diabetic foot ulcers treated with hyperbaric oxygen therapy: a review of the literature

Hyperbaric oxygen therapy (HBO) has been used as an adjunct for healing diabetic foot ulcers (DFUs) for decades. However, its use remains controversial. A literature search was conducted to locate clinical studies and assess the available evidence. Ten prospective and seven retrospective studies evaluating HBO for DFUs were located. These were reviewed and the outcomes were discussed. One study reported no difference in outcomes between patients receiving hyperbaric oxygen and the control group. However, their regime differed from all other studies in that the patients received hyperbaric oxygen twice rather than once daily. Reduced amputation rates and improved healing were the most common outcomes observed.     

Clinical Classification of Bioengineered Skin Use and Its Correlation with Healing of Diabetic and Venous Ulcers

BACKGROUND: Chronic wounds are being treated with bioengineering skin constructs. Yet, there is no standard way of assessing these wounds. We developed a classification system to evaluate wounds after construct application. The classification system evaluates the early clinical effect of bioengineered skin and early construct appearance giving a total score named the skin substitute score. OBJECTIVE: Apply classification system to both venous and diabetic foot ulcers and determine whether classification system has validity and predictability for healing. METHODS: Evaluated serial photographs in 83 and 78 patients with diabetic foot ulcers and in 84 and 83 patients with venous ulcer on Days 7 and 14, respectively, treated with a bilayered bioengineered skin construct. Applied the classification system and determined the percentages of healed patients. RESULTS: There was a significant correlation between better skin substitute score and complete wound closure for both venous ulcers p=0.002 on Day 7 and p=0.01 on Day 14) and diabetic foot ulcers p=0.0005 on Day 7 and p<0.0001 on Day 14). CONCLUSION: Optimal clinical effect was associated with complete wound closure. As the clinical effect becomes less than optimal continued clinical persistence of the construct becomes important. This classification system seems to have validity in predicting complete wound closure in wounds treated with a bilayered bioengineered skin construct.     

Differentiating diabetic foot ulcers that are unlikely to heal by 12 weeks following achieving 50% percent area reduction at 4 weeks

This retrospective analysis included intent-to-treat control patient data from two published, randomised, diabetic foot ulcer (DFU) trials in an effort to differentiate ulcers that are unlikely to heal by 12 weeks despite early healing progress [≥50% percent area reduction (PAR) at 4 weeks]. Predicted and actual wound area trajectories in DFUs that achieved early healing progress were analysed from weeks 5 to 12 and compared for ulcers that did and did not heal at 12 weeks. In 120 patients who achieved ≥50% PAR by week 4, 62 (52%) failed to heal by 12 weeks. Deviations from the predicted healing course were evident by 6 weeks for non healing ulcers. A 2-week delay in healing significantly lowered healing rates (P = 0·001). For DFUs with ≥50% PAR at 4 weeks, those achieving ≥90% versus <90% PAR at 8 weeks had a 2·7-fold higher healing rate at 12 weeks (P = 0·001). A PAR of <90% at 8 weeks provided a negative predictive value for DFU healing at 12 weeks of 82%. For ulcers that fail to progress or worsen from weeks 4 to 6, and those that fail to achieve 90% PAR at 8 weeks, reevaluation of the wound and its treatment is recommended.     

Microscopy visualisation confirms multi‐species biofilms are ubiquitous in diabetic foot ulcers

Increasing evidence within the literature has identified the presence of biofilms in chronic wounds and proposed that they contribute to delayed wound healing. This research aimed to investigate the presence of biofilm in diabetic foot ulcers (DFUs) using microscopy and molecular approaches and define if these are predominantly mono‐ or multi‐species. Secondary objectives were to correlate wound observations against microscopy results in ascertaining if clinical cues are useful in detecting wound biofilm. DFU tissue specimens were obtained from 65 subjects. Scanning electron microscopy (SEM) and peptide nucleic acid fluorescent in situ hybridisation (PNA‐FISH) techniques with confocal laser scanning microscopy (CLSM) were used to visualise biofilm structures. Next‐generation DNA sequencing was performed to explore the microbial diversity. Clinical cues that included the presence of slough, excessive exudate, a gel material on the wound bed that reforms quickly following debridement, poor granulation and pyocyanin were correlated to microscopy results. Of the 65 DFU specimens evaluated by microscopy, all were characterised as containing biofilm (100%, P < 0·001). The presence of both mono‐species and multi‐species biofilms within the same tissue sections were detected, even when DNA sequencing analysis of DFU specimens revealed diverse polymicrobial communities. No clinical correlations were identified to aid clinicians in identifying wound biofilm. Microscopy visualisation, when combined with molecular approaches, confirms biofilms are ubiquitous in DFUs and form either mono‐ or multi‐species biofilms. Clinical cues to aid clinicians in detecting wound biofilm are not accurate for use in DFUs. A paradigm shift of managing DFUs needs to consider anti‐biofilm strategies.     

New techniques for wound debridement

Debridement is a crucial component of wound management. Traditionally, several types of wound debridement techniques have been used in clinical practice such as autolytic, enzymatic, biodebridement, mechanical, conservative sharp and surgical. Various factors determine the method of choice for debridement for a particular wound such as suitability to the patient, the type of wound, its anatomical location and the extent of debridement required. Recently developed products are beginning to challenge traditional techniques that are currently used in wound bed preparation. The purpose of this review was to critically evaluate the current evidence behind the use of these newer techniques in clinical practice. There is some evidence to suggest that low frequency ultrasound therapy may improve healing rates in patients with venous ulcers and diabetic foot ulcers. Hydrosurgery debridement is quick and precise, but the current evidence is limited and further studies are underway. Debridement using a monofilament polyester fibre pad and plasma‐mediated bipolar radiofrequency ablation are both very new techniques. The initial evidence is limited, and further studies are warranted to confirm their role in management of chronic wounds.