Eschar removal by bromelain based enzymatic debridement (Nexobrid ® ) in burns: An European consensus

Molecular immunological mechanisms of impaired wound healing in diabetic foot ulcers (DFU), current therapeutic strategies and future directions

Diabetic foot ulcer (DFU) is a foremost cause of amputation in diabetic patients. Consequences of DFU include infections, decline in limb function, hospitalization, amputation, and in severe cases, death. Immune cells including macrophages, regulatory T cells, fibroblasts and other damage repair cells work in sync for effective healing and in establishment of a healthy skin barrier post-injury. Immune dysregulation during the healing of wounds can result in wound chronicity. Hyperglycemic conditions in diabetic patients influence the pathophysiology of wounds by disrupting the immune system as well as promoting neuropathy and ischemic conditions, making them difficult to heal. Chronic wound microenvironment is characterized by increased expression of matrix metalloproteinases, reactive oxygen species as well as pro-inflammatory cytokines, resulting in persistent inflammation and delayed healing. Novel treatment modalities including growth factor therapies, nano formulations, microRNA based treatments and skin grafting approaches have significantly augmented treatment efficiency, demonstrating creditable efficacy in clinical practices. Advancements in local treatments as well as invasive methodologies, for instance formulated wound dressings, stem cell applications and immunomodulatory therapies have been successful in targeting the complex pathophysiology of chronic wounds. This review focuses on elucidating the intricacies of emerging physical and non-physical therapeutic interventions, delving into the realm of advanced wound care and comprehensively summarizing efficacy of evidence-based therapies for DFU currently available.

Debridement efficacy of serine protease and formulated cream by In Vitro assessment against artificial wound eschar

Chronic wounds typically comprise of necrotic tissue and dried secretions, often culminating in the formation of a thick and tough layer of dead skin known as eschar. Removal of eschar is imperative to facilitate wound healing. Conventional approach for eschar removal involves surgical excision and grafting, which can be traumatic and frequently leads to viable tissue damage. There has been growing interest in the use of enzymatic agents for a gentler approach to debridement, utilizing proteolytic enzymes. In this study, a purified intracellular recombinant serine protease from Bacillus sp. (SPB) and its cream formulation were employed to evaluate their ability to degrade artificial wound eschar; composed of collagen, fibrin, and elastin. Degradation was assessed based on percentage weight reduction of eschar biomass, analysis via sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), and scanning electron microscopy (SEM). Both SPB and its cream formulation were able to degrade up to 50 % artificial wound eschar, with the SPB cream maintaining its degradation efficiency for up to 24 hours. Additionally, the SPB-based cream demonstrated the ability to hydrolyze proteinaceous components of eschars individually (fibrin and collagen) as determined through qualitative assessment. These findings suggest that SPB holds promise for the debridement of wound eschar.

Enzymatic Debridement (Nexobrid) on Burned Hands: Retrospective Review from a Burn Referral Center in Spain

Background

In deep burns, the gold standard of treatment is surgical debridement and coverage, but in hands, this may lead to poor aesthetic and functional results due to the complexity of this anatomical area. Enzymatic debridement (Nexobrid) allows for the preservation of the dermal remnant and reduces the number of skin grafts when compared with surgical excision. The study aimed to analyze the patients with intermediate second-degree or deeper burns in hands who required surgical treatment after Nexobrid and those who avoided it.

Methods

A descriptive retrospective study of all patients who underwent Nexobrid following hand burns between May 2015 and April 2020 treated in Vall d'Hebrón University Hospital was conducted. After the enzymatic debridement, the burn unit team determined if the burn required conservative treatment or surgery, based on the characteristics of the wound bed.

Results

A total of 202 hands were collected. Most hands included in this study had deep second-degree burns (122; 60.4%). Almost half of the hands underwent surgery (99; 49%), and most had deep second-degree burns (61; 61.62%). During follow-up, 24 hands required surgery for sequelae (11.88%) and 62 did not undergo follow-up (30.69%). In the group that needed sequelae surgery, 21 needed surgery after Nexobrid and three of them were healed with conservative treatment after Nexobrid (P < 0.001).

Conclusions

Nexobrid decreases the number of surgical procedures in deep burns of the hand because more conservative attitudes are adopted. Also, it seems to reduce the need of surgery due to burn sequelae.

Assessing antibacterial efficacy of a polyhexanide hydrogel versus alginate-based wound dressing in burns

OBJECTIVE

Burn injuries pose a heightened risk of infection, which is primarily responsible for increased morbidity and mortality. Factors such as extensive skin damage and compromised immunity exacerbate this vulnerability. Pseudomonas aeruginosa and Staphylococcus aureus are frequently identified in burns, with Gram-negative Pseudomonas aeruginosa often resistant to antibacterial agents. While Flaminal, an alginate-based wound dressing (Flen Health, Belgium), aids wound healing, its antibacterial effects are limited compared with 1% silver sulfadiazine (1% SSD). In contrast, Prontosan Wound Gel X, a betaine and polyhexanide-based hydrogel (B. Braun Medical AG, Switzerland), has been shown to effectively combat various microbes and promotes wound healing.

METHOD

In this study, two research cohorts were retrospectively established (control group: patients receiving standard of care with the alginate-based wound dressing; intervention group: patients receiving the polyhexanide hydrogel wound dressing), comprising patients admitted to a burn centre between 2019 and 2022. Patients were eligible when continuous wound treatment with either of the two wound dressings was performed. Laser Doppler imaging (LDI) scans were conducted. Regions of interest (ROIs) were selected based on LDI scans and divided into healing time categories. Wound swabs were collected and the presence of Pseudomonas aeruginosa and Staphylococcus aureus was documented. Bacterial load was evaluated using a semiquantitative scale. Wound healing was recorded.

RESULTS

The control group consisted of 31 patients with 93 ROIs, while the intervention group had 67 ROIs involving 29 patients. Both groups exhibited similar proportions of healing time categories (p>0.05). The polyhexanide hydrogel dressing outperformed the alginate-based dressing in antiseptic efficacy by significantly reducing the incidence of Pseudomonas aeruginosa- and Staphylococcus aureus-positive cultures in patients' wounds. Wound healing time for conservative treatment was comparable between groups.

CONCLUSION

In this study, the polyhexanide hydrogel dressing minimised Pseudomonas aeruginosa and Staphylococcus aureus colonisation in burn wounds, demonstrating strong antibacterial properties, emphasising its potential to minimise infections in burn injuries.

Bacterial nanocellulose loaded with bromelain and nisin as a promising bioactive material for wound debridement

The bacterial nanocellulose (BnC) membranes were produced extracellularly by a novel aerobic acetic acid bacterium Komagataeibacter melomenusus. The BnC was modified in situ by adding carboxymethyl cellulose (CMC) into the culture media, obtaining a BnC-CMC product with denser fibril arrangement, improved rehydration ratio and elasticity in comparison to BnC. The proteolytic enzyme bromelain (Br) and antimicrobial peptide nisin (N) were immobilized to BnC matrix by ex situ covalent binding and/or adsorption. The optimal Br immobilization conditions towards the maximized specific proteolytic activity were investigated by response surface methodology as factor variables. At optimal conditions, i.e., 8.8 mg/mL CMC and 10 mg/mL Br, hyperactivation of the enzyme was achieved, leading to the specific proteolytic activity of 2.3 U/mg and immobilization efficiency of 39.1 %. The antimicrobial activity was observed against Gram-positive bacteria (S. epidermidis, S. aureus and E. faecalis) for membranes with immobilized N and was superior when in situ modified BnC membranes were used. N immobilized on the BnC or BnC-CMC membranes was cytocompatible and did not cause changes in normal human dermal fibroblast cell morphology. BnC membranes perform as an efficient carrier for Br or N immobilization, holding promise in wound debridement and providing antimicrobial action against Gram-positive bacteria, respectively.

Development and Validation of Micro-Azocasein Assay for Quantifying Bromelain

The proteolytic activity of enzymes may be evaluated by a colorimetric method with azocasein. Hence, we developed a micro-assay to quantify bromelain using azocasein. A total of 250 µL of 1.0% azocasein in dH2O was added to 250 µL of test solution, vortexed and incubated at ambient room temperature/30 min. The reaction was terminated with 1500 µL of 5% trichloroacetic acid, vortexed and centrifuged. A total of 150 µL of 0.5M NaOH was added to 150 µL of supernatant in triplicates, and absorbance was recorded at 410 nm. The linearity of the calibration curve was tested with 200-800 µg/mL serial dilutions. The detection limit, precision, accuracy, and robustness were tested along with the substrate enzyme reaction time and solvent matrix effect. Good linearity was seen with serially diluted 200 µg/mL bromelain. The limit of quantification and limit of detection were 5.412 and 16.4 µg/mL, respectively. Intra-day and inter-day analyses showed a relative standard deviation below 2.0%. The assay was robust when tested over 400-450 nm wavelengths. The assays performed using dH2O or PBS diluents indicated a higher sensitivity in dH2O. The proteolytic activity of bromelain was enhanced with L-cysteine or N-acetylcysteine. Hence, this micro-azocasein assay is reliable for quantifying bromelain.

Early Enzymatic Burn Debridement: Results of the DETECT Multicenter Randomized Controlled Trial

Since 1970 surgeons have managed deep burns by surgical debridement and autografting. We tested the hypothesis that enzymatic debridement with NexoBrid would remove the eschar reducing surgery and achieve comparable long-term outcomes as standard of care (SOC). In this Phase 3 trial, we randomly assigned adults with deep burns (covering 3-30% of total body surface area [TBSA]) to NexoBrid, surgical or nonsurgical SOC, or placebo Gel Vehicle (GV) in a 3:3:1 ratio. The primary endpoint was complete eschar removal (ER) at the end of the debridement phase. Secondary outcomes were need for surgery, time to complete ER, and blood loss. Safety endpoints included wound closure and 12 and 24-months cosmesis on the Modified Vancouver Scar Scale. Patients were randomized to NexoBrid (n = 75), SOC (n = 75), and GV (n = 25). Complete ER was higher in the NexoBrid versus the GV group (93% vs 4%; P < .001). Surgical excision was lower in the NexoBrid vs the SOC group (4% vs 72%; P < .001). Median time to ER was 1.0 and 3.8 days for the NexoBrid and SOC respectively (P < .001). ER blood loss was lower in the NexoBrid than the SOC group (14 ± 512 mL vs 814 ± 1020 mL, respectively; P < .0001). MVSS scores at 12 and 24 months were noninferior in the NexoBrid versus SOC groups (3.7 ± 2.1 vs 5.0 ± 3.1 for the 12 months and 3.04 ± 2.2 vs 3.30 ± 2.76 for the 24 months). NexoBrid resulted in early complete ER in >90% of burn patients, reduced surgery and blood loss. NexoBrid was safe and well tolerated without deleterious effects on wound closure and scarring.

Enzymatic debridement with bromelain and development of bacteremia in burn injuries: A retrospective cohort study

BACKGROUND

Debridement is crucial for effective wound management in patients with severe burn injuries, and bromelain, a proteolytic enzyme from pineapple stems, has emerged as a promising alternative for surgery. However, potential links of bromelain use to fever and sepsis have raised some concerns. Given the uncertainty as to whether this was caused by infection or other inflammatory sources, we aimed to investigate if the use of topical bromelain was associated with bacteremia.

METHODS

This single-centre retrospective cohort study included critically ill adult patients with severe burn injuries hospitalised at the Burn Center of the University Hospital Zurich between January 2017 and December 2021. Data were collected from two in-hospital electronic medical records databases. Our primary outcome, the association between topical bromelain treatment and the development of bacteremia, was investigated using a competing risk regression model, taking into account the competing risk of death. As a secondary outcome, the relationship between bromelain treatment and overall ICU mortality was examined using a Cox proportional hazards model.

RESULTS

The study included 269 patients with a median age of 50 years and median burnt total body surface area of 19%. A first bacteremia occurred in 61 patients (23%) after a median time of 6 days. Bromelain treatment was given to 83 (31%) of patients, with 22 (27%) of these developing bacteremia. In the fully adjusted competing risk regression model, no evidence for an association between bromelain treatment and bacteremia was found (SHR 0.79, 95%CI 0.42-1.48, p = 0.47). During hospital stay, 40 (15%) of patients died. There was no significant difference in mortality between patients treated with bromelain and those who were not (HR 0.55, 95%CI 0.26-1.20, p = 0.14). Among the five multidrug-resistant (MDR) pathogens identified, three were found in patients with bromelain treatment.

CONCLUSION

Our study did not confirm an association between topical bromelain and bacteremia in patients with severe burn injuries. This finding can inform evidence-based practices by addressing concerns about potential risks of bromelain use, contributing to the development of more effective and safe burn wound management strategies.

The use of NexoBrid™ enzymatic debridement and coagulation abnormalities

OBJECTIVES

Current evidence on how the use of bromelain-based enzymatic debridement techniques (NexoBrid™) affect patient coagulation is limited. A single patient case report [1] suggests that a patient with 15% total body surface area (TBSA) burn developed decreased coagulation activity following debridement with NexoBrid™ enzymatic debridement (ED). Regional Burns Centres in the United Kingdom may be reluctant to use ED, particularly in larger burns, citing concerns regarding coagulation. At our centre we have routinely used ED on deep partial thickness burns since 2017 including on patients with burns over 15% TBSA. This study aims to investigate whether there is a significant disruption in coagulation in patients undergoing ED with burns > 15% TBSA or admitted to intensive care compared to the standard of care (SOC) which is surgical debridement in theatre.

METHODS

This single-centre retrospective study includes all patients with a burn treated with ED at Pinderfields General Hospital Regional Burns Centre intensive care unit (ITU) from 2017 to 2020. Patients were matched to those treated with SOC at the same centre by age, % TBSA burn and presence of inhalational injury. These parameters correlate with the Baux score [9]. Percentage of burn debrided was matched as closely as possible, with coagulation profiles and platelet count taken the day before, the day of and three days following surgery.

RESULTS

Thirty-one patients were treated with ED in the intensive care unit between 2017 and 2020. Four patients were excluded due to insufficient records and one patient was anti-coagulated. Twenty-six patients were included and matched as described above. Average age of patients receiving ED was 44 years, the same in the matched group. Average TBSA burn is 35.5% (35.8% in matched group). No statistically significant difference in coagulation was seen between patients undergoing ED compared to SOC when considering prothrombin time (PT), activated partial thromboplastin time (aPTT) and platelet count. Both groups slightly breached the upper limit of normal on day 2 post ED and SOC. There was a slight breach of the lower limit of the average platelet count on day 2 post-ED which was neither statistically nor clinically significant.

CONCLUSIONS

Large burns are associated with coagulation abnormalities, therefore isolating a single variable in this cohort is challenging. However, this study found no significant change following ED use when compared to SOC and therefore no convincing evidence that ED is associated with coagulation abnormalities. This study represents one of the largest focusing on coagulation abnormalities following the use of ED, as the current literature is limited. Our study suggests that concerns regarding coagulation abnormalities should not prevent patients with large, deep partial thickness burns or full thickness burns being treated with ED.

[Surgical management of burn injury patients : Comments on the guidelines on treatment of thermal injuries in adults]

The treatment of burn injury patients is a unique challenge for clinicians. The extent of thermal injuries ranges from very small burns to life-threatening burn injuries. Insufficient treatment can result in a substantial impairment in the quality of life. In order to avoid such sequelae a targeted treatment must be carried out. A precise diagnosis determines the necessary treatment. Superficial second-degree burns (2a) not involving the face, hand or joints with a total body surface area smaller than 10% can usually be treated with modern wound dressings in an outpatient setting. Deep second-degree burns (2b) are an indication for debridement. In addition to the classical surgical procedures with tangential excision, enzymatic debridement can also be employed. Similarly, indeterminate burns (2a/2b) are also considered to be an indication for enzymatic debridement. Third-degree burns are treated with early debridement and skin grafting. These patients can also benefit from special dermal replacement procedures for an improvement of the functional and esthetic results. Due to the long-term visible sequelae of burns, aftercare of these patients is indicated.

Bromelain-based enzymatic burn debridement: A systematic review of clinical studies on patient safety, efficacy and long-term outcomes

In 2012 the European Medicines Agency approved a pineapple stem-derived Bromelain-based debridement concentrate of proteolytic enzymes (NexoBrid®, MediWound Ltd, Yavne, Israel) for adult deep burns. Over 10 000 patients have been successfully treated with NexoBrid® globally, including in the US. The aim of our study is to perform a systematic review of the current literature on Nexobrid® outcomes. We conducted a literature search in PubMed, Google Scholar, Embase, and other search engines (2013-2023). The online screening process was performed by two independent reviewers with the Covidence tool. The protocol was reported using the Preferred Reporting Items for Systematic Review and Meta-Analyses, and it was registered at the International Prospective Register of Systematic Reviews of the National Institute for Health Research. We identified 103 relevant studies of which 34 were found eligible. The included studies report the positive effects of Nexobrid® on burn debridement, functional and cosmetic outcomes, scarring, and quality of life. Also, they validate the high patient satisfaction thanks to enhanced protocols of analgosedation and/or locoregional anaesthesia during Bromelain-based debridement. Two studies investigate potential risks (coagulopathy, burn wound infection) which concluded there is no strong evidence of these adverse events. NexoBrid® is a safe, selective, non-surgical eschar removal treatment modality. The benefits of Bromelain-based debridement are faster debridement and healing times, reduced operations, length of stay, cases of sepsis, blood transfusions, and prevention of compartment syndrome. Existing evidence suggests that the indications and the role of Bromelain-based debridement are expanding to cover "off-label" cases with significant benefits to the global healthcare economy.

[Surgical management of burn injury patients : Comments on the guidelines on treatment of thermal injuries in adults]

The treatment of burn injury patients is a unique challenge for clinicians. The extent of thermal injuries ranges from very small burns to life-threatening burn injuries. Insufficient treatment can result in a substantial impairment in the quality of life. In order to avoid such sequelae a targeted treatment must be carried out. A precise diagnosis determines the necessary treatment. Superficial second-degree burns (2a) not involving the face, hand or joints with a total body surface area smaller than 10% can usually be treated with modern wound dressings in an outpatient setting. Deep second-degree burns (2b) are an indication for debridement. In addition to the classical surgical procedures with tangential excision, enzymatic debridement can also be employed. Similarly, indeterminate burns (2a/2b) are also considered to be an indication for enzymatic debridement. Third-degree burns are treated with early debridement and skin grafting. These patients can also benefit from special dermal replacement procedures for an improvement of the functional and esthetic results. Due to the long-term visible sequelae of burns, aftercare of these patients is indicated.

Comparative Clinical Study of Suprathel® and Jelonet® Wound Dressings in Burn Wound Healing after Enzymatic Debridement

Following the enzymatic debridement of deep dermal burns, the choice of wound dressing is crucial for providing an adequate environment and suitable conditions for rapid wound healing. As Suprathel® and fatty gauze (Jelonet®) are the most commonly used dressings in burn centers, the aim of this study is to compare Suprathel® and Jelonet® in the treatment of deep dermal burns after enzymatic debridement with respect to wound healing, patient comfort, and pain. A total of 23 patients with deep dermal burns of the hand or foot (mean total body surface area of 4.31%) were included in this prospective, unicentric, open, comparative, and intra-individual clinical study. After enzymatic debridement, wounds were divided into two areas: one was treated with Suprathel® and the other with Jelonet®. Suprathel® remained on the wounds without dressing changes while Jelonet® was regularly changed. Wound healing, infection, bleeding, exudation, time for dressing changes, and pain were documented (from days 2 to 48) after injury. Satisfactory results were obtained in 22 cases; only one patient had to undergo a second debridement followed by skin grafting. No significant difference in time to final wound healing could be observed (18-19 d). Patients reported significantly less pain during the dressing changes for Suprathel® compared to Jelonet®. Furthermore, the wound areas treated with Suprathel® showed significantly less exudation and bleeding. Wound infections rarely occurred in both groups. In conclusion, the authors found that both wound dressings could be used to achieve safe and rapid wound healing after the enzymatic debridement of deep dermal burns of the hands and feet. However, compared to Jelonet®, Suprathel® showed superior results in terms of patient comfort and pain reduction.

Anacaulase-bcdb for the treatment of severe thermal burns

INTRODUCTION

Accurate burn depth assessment and early excision of burn eschar with maximal dermal preservation are key concepts in the optimal care of burn injury. Although excision with knife has long since been standard of care, a newer technique for wound bed preparation utilizing a bromelain-based enzyme has gained popularity worldwide and may offer several advantages.

AREAS COVERED

Here we report the pharmacologic properties, evidence for clinical efficacy, safety, and tolerability of anacaulase-bcdb for the treatment of deep partial thickness and full thickness burns.

EXPERT OPINION

Anacaulase-bcdb is a safe, non-surgical, selective eschar removal agent. It offers advantages over surgical excision of burn with knife and fulfills two unmet needs: burn depth assessment and dermal preservation during excision. Evidence supports a faster time to complete eschar removal; reduced number of operations; reduction in the amount of autografting, length of stay, and blood loss; prevention of burn induced compartment syndrome; and improved cosmetic outcome.

FDA Approvals of Biologics in 2022

The year 2022 witnessed the control of the COVID-19 pandemic in most countries through social and hygiene measures and also vaccination campaigns. It also saw a decrease in total approvals by the U.S. Food and Drug Administration (FDA). Nevertheless, there was no fall in the Biologics class, which was boosted through the authorization of 15 novel molecules, thus maintaining the figures achieved in previous years. Indeed, the decrease in approvals was only for the category of small molecules. Monoclonal antibodies (mAbs) continued to be the drug class with the most approvals, and cancer remained the most targeted disease, followed by autoimmune conditions, as in previous years. Interestingly, the FDA gave the green light to a remarkable number of bispecific Biologics (four), the highest number in recent years. Indeed, 2022 was another year without the approval of an antimicrobial Biologic, although important advancements were made in targeting new diseases, which are discussed herein. In this work, we only analyze the Biologics authorized in 2022. Furthermore, we also consider the orphan drugs authorized. We not only apply a quantitative analysis to this year's harvest, but also compare the efficacy of the Biologics with those authorized in previous years. On the basis of their chemical structure, the Biologics addressed fall into the following classes: monoclonal antibodies; antibody-drug conjugates; and proteins/enzymes.

Enzymatic Debridement in Geriatric Burn Patients—A Reliable Option for Selective Eschar Removal

The treatment of geriatric burn patients represents a major challenge in burn care. The objective of this study was to evaluate the efficacy of enzymatic debridement (ED) in geriatric burn patients. Adult patients who received ED for treatment of mixed pattern and full thickness burns (August 2017–October 2022) were included in this study and grouped in the younger (18–65 years) and geriatric (≥65 years) groups. Primary outcome was a necessity of surgery subsequent to ED. Both groups (patient characteristics, surgical and non-surgical treatment) were compared. Multiple logistic and linear regression models were used to identify the effect of age on the outcomes. A total of 169 patients were included (younger group: 135 patients, geriatric group: 34 patients). The burn size as indicated by %TBSA (24.2 ± 20.4% vs. 26.8 ± 17.1%, p = 0.499) was similar in both groups. The ASA (2.5 ± 1.1 vs. 3.4 ± 1.1, p < 0.001) and ABSI scores (6.1 ± 2.8 vs. 8.6 ± 2.3, p < 0.001) were significantly higher in the geriatric group. The %TBSA treated with ED (5.4 ± 5.0% vs. 4.4 ± 4.3%, p = 0.245) were similar in both groups. The necessity of additional surgical interventions (63.0 % vs. 58.8 %, p = 0.763) and the wound size debrided and grafted (2.9 ± 3.5% vs. 2.2 ± 2.1%; p = 0.301) were similar in both groups. Regression models yielded that age did not have an effect on efficacy of ED. We showed that ED is reliable and safe to use in geriatric patients. Age did not have a significant influence on the surgical outcomes of ED. In both groups, the size of the grafted area was reduced and, in many patients, surgery was avoided completely.

Reducing Blood Loss in a Burn Care Unit: A Review of Its Key Determinants

Patients with a major burn injury differ considerably from the typical critical ill and trauma population. Very often, burn patients suffer from anemia throughout their hospital stay. This is caused both by combination of persistent blood loss with decreased erythropoiesis. Therefore, burn patients do have major transfusion requirements. However, transfusion is not devoid of risks or costs. We hereby review the best surgical techniques and medical approaches, aiming to reduce blood loss in a burn patient and optimize red cell production, so that we can reduce the need of RBC transfusion. The implementation of a combination of surgical techniques aiming to reduce blood loss and medical care approaches to prevent anemia, rather than single attitudes, should be adopted in burn care. There is an urgent need for clear guidelines that can easily be accepted, applied, and spread across different burn units to methodically implement measures to reduce blood loss and transfusion needs, and ultimately improve burn patients' outcome and the health care financial status.

Enzymatic debridement for circumferential deep burns: the role of surgical escharotomy

INTRODUCTION

Circumferential deep burns carry a high risk for a burn induced compartment syndrome. It was recently shown that an enzymatic bromelain-based debridement with Nexobrid® is a safe and efficient procedure to release pressure in deep circumferential extremity burns reducing the need for surgical escharotomy. We therefore herein aimed to analyze the conceptual relation between Nexobrid® and surgical escharotomy.

PATIENTS AND METHODS

We conducted a retrospective study on all patients with circumferential deep partial-thickness or full-thickness burns requiring immediate escharotomy that was either performed by surgical incision or Nexobrid®. Medical records of 792 patients that were treated at the burn center of the University Hospital Zurich between 2016 and 2021 were analyzed.

RESULTS

Overall, 62 patients with circumferential deep partial-thickness or full-thickness burns who received preventive decompression either by Nexobrid® (N = 29) or surgical escharotomy (N = 33), were included. Whilst distribution of age, sex, BMI and type of injury showed no difference between the groups, the ABSI score, TBSA, percentage of third degree burns and mortality were significantly higher in patients who received a surgical escharotomy.

CONCLUSION

While the use of Nexobrid® to prevent burn induced compartment syndrome has steadily increased, surgical escharotomies were predominantly performed in severely burned patients with a high degree of full-thickness burns. Thus, higher mortality in this patient group needs to be considered with caution and is mainly attributed to the higher TBSA. Although evidence is lacking for the use of Nexobrid® for larger body areas exceeding 15%, escharotomy is also the more reliable and faster approach in such critically burned patients.

Enzymatic Debridement of Deep Thermal Burns in the Russian Federation: First Experience

Since its approval in Europe a decade ago, NexoBrid^® enzymatic debridement of deep thermal burns has been gaining acceptance as standard practice around the world. The purpose of this study is to report the first experience with NexoBrid^® in the Russian Federation. During 2019-2020, we conducted a post-registration clinical study assessing the safety and treatment results of NexoBrid^® enzymatic debridement. The study involved 15 adult patients suffering from deep thermal burns over an area ≤15% of their total body surface area. Patients were treated with NexoBrid^® within 3 days of injury, followed by spontaneous or surgical wound closure. Complete eschar removal was achieved in twelve patients, 80% eschar removal in two patients, and 70% in one patient. Complete spontaneous epithelialization of wounds was achieved in 12 patients (80%) within 18 ± 1.9 days after the start of treatment. We did not witness pathological scarring during follow-up, and there were no significant safety issues throughout the study. Early use of NexoBrid^® resulted in rapid, effective, and safe eschar removal with good results and sufficient preservation of viable dermis to allow for spontaneous healing in 80% of patients. These results demonstrate the ability to minimize surgical intervention and hopefully lead to better long-term scarring results.

Helpful hints in deciding what and when to operate after enzymatic debridement

INTRODUCTION

In recent years, it has become clear that the burn eschar in deep burns can be selectively removed using the enzymatically debriding agent NexoBrid® (EDNX). In deep partial-thickness burns, such selective debridement preserves all non-injured dermis, which is sometimes sufficient for spontaneous re-epithelization. Nevertheless, it can be extremely challenging to determine exactly what and when to operate after an EDNX procedure. In this manuscript, we sought to investigate the clinical aspect of the enzymatically debrided wound bed of laser Doppler imaging (LDI)-confirmed deep dermal and full-thickness burns after NexoBrid® application. This to evaluate the residual wound healing capacity and implement specific indications for surgical therapy after enzymatic debridement.

MATERIAL AND METHODS

Mainly LDI-blue areas, determined between 48 h and 5d after burn and afterwards treated with EDNX were selected. Six practical and three expert EDNX users evaluated the high-quality digital images of the wound beds immediately post NexoBrid® removal and after a 2 h wet-to-dry (WTD) dressing period.

RESULTS

One hundred and two mainly LDI-blue areas in 32 patients were analyzed. Regarding the early decision-making, there were no significant differences in the wound bed evaluations, wound healing assessment and treatment decision of all 9 EDNX users post EDNX removal versus post WTD. Moreover, there was a good to excellent consensus between the practical and expert EDNX users in the individual wound bed evaluations. Even in the evaluation of a newly developed wound bed color code, with 7 different colors/patterns to choose from, the consensus was 80%. There was also an 84% consensus on the decision whether or not to operate. All mainly LDI-blue areas with incomplete enzymatic debridement, determined during clinical investigation by expert EDNX users, required surgery. Additionally, the expert investigators demonstrated that the following wound bed characteristics were independent predictors of the need for surgical treatment: visible fat lobules (p = 0.028), translucent fat lobules (p < 0.001), dermal step-off in the wound bed (p < 0.001), visible blood vessels (p < 0.001) and coagulated blood vessels (p = 0.023). Also, higher color code ranges on our own developed wound bed classification were significantly related to a surgical intervention (p = 0.006). When including the LDI flux values, the perfusion units were significantly different (p < 0.001) between the exclusively LDI-blue areas treated conservatively (mean 145.7) and the areas ultimately treated with autografts (mean 119.5).

CONCLUSION

To the best of our knowledge, this study is the first to address the clinical wound bed evaluation of LDI-confirmed deep burns after NexoBrid® application. Based on our results, it is recommended to evaluate the wound bed twice: immediately after removing NexoBrid® to assess the viability of the wound bed and after the WTD period to reach a more complete decision. During these evaluations, wound bed characteristics such as incomplete debridement, visible and/or translucent fat lobules, visible and/or coagulated blood vessels and a dermal step-off in the wound bed combined with a higher range (4-5) in the newly developed wound bed color code should lead to an early and reliable decision for skin grafting. For burn centers using LDI, mean flux values below 119.5PU - in addition to the above-mentioned wound bed evaluation - are a clear indicator for surgical therapy.

Surgical Repair of the Acute Burn Wound: Who, When, What Techniques? What Is the Future?

Modern burns surgery is multidisciplinary, multimodal and includes a dermal preservation approach. The management of the surgical wound starts in the pre-hospital environment with stabilization and assessment of the burn injured patient according to protocols of trauma resuscitation with special emphasis in the assessment of the burn depth and surface area. A large burn requires fluid resuscitation and physiological support, including counterbalancing hyper metabolism, fighting infection and starting a long burns intensive care journey. A deep burn may impose the need for surgical debridement and cover through a staged approach of excision of devitalized tissue depending on its extension and patient circumstances. These methodologies warrant patients survivability and require professionals integrated in a multidisciplinary team sharing decisions and directing management. Burns Multimodality involves multiple techniques used according to patient's needs, wound environment, operators experience and available resources. Traditional practices used together with new techniques may reduce morbidity and operative time but also challenge stablished practice. The concept of using the best teams with the best techniques combines with the need for selective and judicious surgery that preserves tissue architecture and spares as much as possible dermal component, therefore reducing the possibility of functional impairment and cosmetic embarrassment caused by pathological scars. Who is best placed to perform these tasks, the appropriate or best timing of surgery and the different practices used to achieve best results will be discussed, together with a reflection on what the future holds for these fundamental steps in the management of the burn injured patient turning into a functional burn survivor.

Enhancing the accuracy of surgical wound excision following burns trauma via application of Rapid Evaporative IonisationMass Spectrometry (REIMS)

BACKGROUND

Surgical wound excision is a necessary procedure for burn patients that require the removal of eschar. The extent of excision is currently guided by clinical judgement, with excessinto healthy tissue potentially leading to excessive scar, or inadequate debridement increasing risk of infection. Thus, an objective real-time measure to facilitate accurate excision could support clinical judgement and improve this surgical procedure. This study was designed to investigate the potential use of Rapid evaporative ionisation mass spectrometry (REIMS) as a tool to support data-driven objective tissue excision.

METHODS

Data were acquired using a multi-platform approach that consisted of both Rapid Evaporative Ionisation Mass Spectrometry (REIMS) performed on intact skin, and comprehensive liquid chromatography-mass spectrometry (LC-MS/MS) lipidomics performed on homogenised skin tissue extracts. Data were analysed using principal components analysis (PCA) and multivariate orthogonal projections to latent squares discriminant analysis (OPLS-DA) and logistic regression to determine the predictability of the models.

RESULTS

PCA and OPLS-DA models of the REIMS and LC-MS/MS lipidomics data reported separation of excised and healthy tissue. Molecular fingerprints generated from REIMS analysis of healthy skin tissue revealed a high degree of heterogeneity, however, intra-individual variance was smaller than inter-individual variance. Both platforms indicated high levels of skin classification accuracy. In addition, OPLS-DA of the LC-MS/MS lipidomic data revealed significant differences in specific lipid classes between healthy control and excised skin samples; including lower free fatty acids (FFA), monoacylglycerols (MAG), lysophosphatidylglycerol (LPG) and lysophosphatidylethanolamines (LPE) in excised tissue and higher lactosylceramides (LCER) and cholesterol esters (CE) compared to healthy control tissue.

CONCLUSIONS

Having established the heterogeneity in the biochemical composition of healthy skin using REIMS and LC-MS/MS, our data show that REIMS has the potential to distinguish between excied and healthy skin tissue samples. This pilot study suggests that REIMS may be an effective tool to support accurate tissue excision during burn surgery.

Preliminary Single-Center Experience of Bromelain-Based Eschar Removal in Children with Mixed Deep Dermal and Full Thickness Burns

Introduction: Early eschar removal is the standard management of burns. The goal is to remove all of the necrotic tissue and render the wound suitable for healing or skin grafting. The enzymatic debridement of burn wounds allows for minimally invasive removal of burn eschar. The aim of the study was to describe and compare the demographic characteristics, surgical treatment and outcomes of patients treated with Nexobrid® with patients who had standard surgical excision. Material and Methods: A retrospective review was conducted on children who underwent enzymatic debridement. The study group was compared with children treated with the standard of care (SoC). Results: Twelve children (mean age 8 years, range 3 to 15 years) with mixed deep dermal and full thickness burn wounds were treated with Nexobrid®. The mean size of the burns was 29% TBSA. The median percentage TBSA debrided using Nexobrid® was 15% (range 2–27%). In a clinical assessment, enzymatic debridement was effective in removing dead tissue in a single application. No adverse reaction to Nexobrid® and serious complications after enzymatic procedure were recorded in the study group. The estimated relative risk of the need for reconstructive procedures decreases 3.5 times for the study group (RR 3.5, 95%CI 0.9–13.5, p = 0.089). Conclusion: The bromelain-based enzymatic method offers a good and safe debridement option to improve the treatment and life quality of children with severe burns. The main outcome of interest was the number of reconstructive procedures due to scar contractures, which was reduced in the group treated enzymatically compared to the SoC-treated children.

Evaluation of Bromelain-Based Enzymatic Debridement Combined with Laser Doppler Imaging and Healing of Burn Wounds

Background

Accurate estimation of burn depth is crucial for correct treatment decision making. Bromelain-based enzymatic debridement (ED) may improve clinical assessment of burn depth. Laser Doppler imaging (LDI) provides a valuable indicator of burn depth by analyzing microcirculation within tissue beds. This study aimed to evaluate bromelain-based enzymatic debridement combined with laser Doppler imaging and healing of 42 wounds in 19 patients with mixed second- and third-degree thermal burns.

Material/Methods

We included 42 wounds in 19 patients with mixed deep dermal and full-thickness thermal burns. All patients were treated with eschar-specific removal agent for ED. The perfusion of each wound after ED was assessed using LDI. Healing time was estimated by 2 experienced burn surgeons and marked by the observation of epithelization. The usefulness of the LDI performed after ED in predicting healing time was estimated. The findings were analyzed to determine a cut-off value for LDI that indicates if a burn will heal spontaneously.

Results

We observed that burn wounds with higher mean perfusion healed faster. The analysis showed a strong relationship between perfusion after ED and healing time (Spearman rank correlation coefficient=−0.803). A mean perfusion greater than 296.89 indicated that the wound could heal spontaneously and does not require skin grafting.

Conclusions

LDI examination of an already debrided wound allows for a reliable assessment of perfusion at an early stage of treatment. The use of a safe and effective debridement method in conjunction with a non-invasive diagnostic tool could improve burn management.

Enzymatic debridement in scalds is not as effective as in flame burns regarding additional eschar excision: A retrospective matched-control study

OBJECTIVE

Enzymatic debridement of burn eschar became an accepted and widely used technique for burn wound treatment over the last years. However, this practice is not exempt from failure and recent experimental studies indicate that it may not be as efficient in scalds as in flame burns.

METHODS

Patients that were admitted to the burn intensive care unit between June 2017 and February 2021 and received enzymatic debridement within the first 72 h after scald and flame burn were included. Patients with scald burns were matched regarding age, sex and per cent total body surface area (%TBSA) burned in a 1:2 ratio with patients presenting with flame burns.

RESULTS

Eighteen patients with scald burns were matched with 36 with flame burns. After matching, both groups were similar in terms of age (flame burns 44.5 ± 21.1 years vs. scald 41.8 ± 22.6 years, p = 0.666), and %TBSA burned (11.0 ± 8.2% vs. 10.6 ± 9.6%, p = 0.851). Patients with scald burns significantly more often underwent further surgical eschar excision compared to controls (scald 16 (88.9%) vs. flame 19 (52.8%), p = 0.016). Length of stay per %TBSA was significantly longer in scald burns (scald 7.8 ± 9.2 days vs. flame 3.7 ± 3.8, p = 0.013).

CONCLUSION

This study indicates that enzymatic debridement may not be as effective in scalds as in flame burns. It was shown that patients with scalds and subsequent enzymatic debridement more frequently underwent additional surgical intervention and that the size of the transplanted area was larger compared to control. Moreover, those patients had a longer length of stay at the hospital per %TBSA burned.

Enzymatic debridement in critically injured burn patients - Our experience in the intensive care setting and during burn resuscitation

BACKGROUND

Much of the recent literature on bromelain based enzymatic debridement of burn injury has focused on its use in smaller burn injury and specialist areas such as the hands or genitals (Krieger et al., 2012; Schulz et al., 2017a,b,c,d). This is despite the original papers describing its use in larger burn injury (Rosenberg et al., 2004, 2014). The current EMA license for Nexobrid™ advises that it should not be used for burn injuries of more than 15% TBSA and should be used with caution in patients with pulmonary burn trauma and suspected pulmonary burn trauma. The original safety and efficacy trial of NexoBrid™ limited its use to 15% TBSA aliquots with concern regarding the effect of bromelain on coagulation. In a European consensus paper of experienced burns clinicians, now on its second iteration, 100% of respondents agreed that "up to 30% BSA can be treated by enzymatic debridement based on individual decision" (Hirche et al., 2017). Hofmaenner et al.'s recent study on the safety of enzymatic debridement in extensive burns larger than 15% provides some further evidence that "bromelain based enzymatic debridement can be carried out safely in large-area burns" (Hofmaenner et al., 2020) but the literature is scant in these larger debridement areas. In our centre we have been using enzymatic debridement for resuscitation level burn injury since 2016. We have gained significant learning in this time; this article aims to describe our current protocol for enzymatic debridement in this patient population and highlight specific learning points that might aid other centres in using enzymatic debridement for larger burn injury.

METHOD

We performed a search of the IBID database to identify all adult patients who satisfied the inclusion criteria of resuscitation level burn injury (defined as total burn surface area (TBSA) ≥15% in patients aged >16 years), or level 3 admission following burn injury and who underwent Enzymatic Debridement. A case note review was completed, and details comprising patient demographics, TBSA, mechanism of burn, presence of inhalation injury, sequencing of debridement, length of ICU and hospital stay, blood product utilisation and the need for autografting were recorded. No ethical approval has been sought for this retrospective review.

RESULTS

We identified 29 patients satisfying the inclusion criteria (Table 1). Between June 2016 and June 2020 the average total burn size of patients who had at least some of their burn treated by enzymatic debridement increased from 21.4% in 2016/17 to 34.7% in 2019/20. In these patients the actual area treated by enzymatic debridement also increased from 11.9% TBSA to 20.3% TBSA. 19 patients (66%) had enzymatic debridement performed within 24 h of injury, a further 2 patients (7%) within 48 h after injury. Patients were more likely to have enzymatic debridement commenced in the first 24 h after injury if they had circumferential limb injury (39% vs 9%) or were planned for enzyme only debridement (78% vs 28%). Those who were planned for combination enzyme and surgical debridement were more likely to have enzymatic debridement commenced after the first 48 h (75%). We have performed enzymatic debridement overnight on one occasion, for a patient who presented with circumferential limb injury and was determined to undergo urgent debridement.

CONCLUSION

Much of the literature has described the use of enzymatic debridement in smaller burns, and specialist areas. However, it is our opinion that the advantages of enzymatic debridement appear to be greater in larger burns with a facility for whole burn excision on the day of admission in the ICU cubicle. We have demonstrated significantly reduced blood loss, improved dermal preservation, reduced need for autografting, and a reduction in the number of trips to theatre. We would advocate that both the team and the patient need to be as prepared as they would be for a traditional surgical excision. The early part of our learning curve for enzymatic debridement in resuscitation level injuries was steep, and we were able to build on experience from managing smaller injuries. We recommend any team wishing to using enzymatic debridement gain experience in the same way and develop robust local pathways prior to attempting use in larger burn injuries.

Enzymatic debridement: past, present, and future

INTRODUCTION

Early surgical debridement of the deep second and third-degree burns is still the standard of care (SOC) to prepare the wound bed for skin grafting. However, this technique has some drawbacks that explain the growing interest in enzymatic debridement as an alternative. In this article, we provide a historic overview as well as the current state-of-the-art and future prospective of this type of non-surgical debridement.

MATERIALS AND METHODS

A narrative review of the available literature was conducted using a systematic search.

RESULTS

A total of 32 articles were included. The only enzyme mixture still used nowadays for burn eschar removal is bromelain-based. There is increasing evidence that this type of enzymatic debridement is a powerful tool to selectively remove the eschar in deep burns, thereby reducing the need for autologous skin grafting compared to surgical SOC. Moreover, off-label use of enzymatic debridement with NexoBrid^® (facial, pediatric, and >15%TBSA burns) has proven to be effective and safe.

CONCLUSION

There is increasing evidence that bedside administered NexoBrid^®, preferably under regional anesthesia, is a powerful tool for selective burn eschar removal. However, the clinical wound bed evaluation post-NexoBrid^® procedure in relation to the optimal treatment decision-conservative treatment vs. surgery-is not yet completely elucidated. More high-quality prospective clinical trials are necessary to compare enzymatic debridement of objectively confirmed deep burns with the current standard treatment and assess the effectiveness of the eschar removal, the need for surgery, the healing time of such wounds, and the long-term scar quality.

Burns in Israel: Etiologic, Demographic, and Clinical trends—A 9-Year Updated Comprehensive Study, 2004–2010 versus 2011–2019

Based on the Israeli National Trauma Registry (INTR) data, this study reports etiological, demographic, and clinical trends and includes all admissions to burn and trauma centers across Israel from 2011 to 2019 and compares these with 2004 to 2010 rates. From 2011 to 2019, 5,710 patients were admitted to burn centers across Israel. Children aged 0 to 1 years (25.9%), non-Jews (40.7%), and males (67.2%) remain the main groups of the burn casualties. Most of the casualties sustained 1 to 9% total body surface area (TBSA) burns with various depths. Scalds were less fatal than fire/flame-related casualties (<1 vs. 11.5%). Fewer surgical procedures were conducted for burns under 9% TBSA compared with greater TBSA. The percentage of TBSA and burn depth were found to be the most significant predictor of mortality among all age groups (>200 times increased risk with full-thickness burns >30% TBSA burn) and correlated with prolonged length of stay (>7 days).

Pain management during a bromelain-based selective enzymatic debridement in paediatric and adult burn patients

BACKGROUND

Pain associated with surgical or enzymatic burn wound debridement prevents many burn centres from working outside an operating theatre, creating a burden. Alternatives for general anaesthesia to manage pain in burn patients treated with enzymatic debridements, such as regional anaesthesia, have not been studied in detail. This study explores the different possibilities for pain management during a bedside NexoBrid™ procedure.

MATERIAL AND METHODS

We performed a single-centre retrospective study that included 82 paediatric, adolescent, and adult patients with deep dermal and full-thickness burns treated bedside with NexoBrid™ under regional or general anaesthesia. Outcome measures were pain during the NexoBrid™ procedure, the safety of the anaesthesia and the NexoBrid™ procedure, logistics of the bedside NexoBrid™ procedure, and time to wound closure.

RESULTS

Forty-three patients in the adult group (43/67, 64%) only presented with burn wounds on one upper or the one or two lower extremities. In 29 of them (29/43, 67%), a NexoBrid™ procedure was performed under regional anaesthesia, which resulted in low pain levels without any adverse events. All seven patients in the paediatric group, where only one upper or one or two lower limbs were involved (7/15, 47%), underwent a NexoBrid™ procedure performed under regional anaesthesia where no adverse events were reported. In these children, the use of regional anaesthesia was associated with a significant decrease in time to wound closure (average treatment effect on the treated = -22.5 days, p = 0.021).

CONCLUSION

This study highlights that regional anaesthesia administered at the bedside should be the method of choice for pain management during NexoBrid™ procedures because often, it can be adequately and safely performed in all age groups. This approach will reduce the burden on operating theatres. A flow chart has been developed to guide pain management during a NexoBrid™ procedure.

Bromelain and Nisin: The Natural Antimicrobials with High Potential in Biomedicine

Infectious diseases along with various cancer types are among the most significant public health problems and the leading cause of death worldwide. The situation has become even more complex with the rapid development of multidrug-resistant microorganisms. New drugs are urgently needed to curb the increasing spread of diseases in humans and livestock. Promising candidates are natural antimicrobial peptides produced by bacteria, and therapeutic enzymes, extracted from medicinal plants. This review highlights the structure and properties of plant origin bromelain and antimicrobial peptide nisin, along with their mechanism of action, the immobilization strategies, and recent applications in the field of biomedicine. Future perspectives towards the commercialization of new biomedical products, including these important bioactive compounds, have been highlighted.

The process to obtain reimbursement for enzymatic debridement in clinically deep burns

INTRODUCTION

Burn eschar removal by enzymatic debridement with NexoBrid^® (EDNX) results in a maximum preservation of all viable tissue, which is the main advantage over traditional tangential excision. The authors participated in a marketing authorization holder process to obtain reimbursement from the national health authorities in Belgium.

MATERIAL AND METHODS

The reimbursement process consisted of three phases, as specified by the reimbursement regulations required by the Belgian National Institute for Health and Disability Insurance (NIHDI).

RESULTS

Forty-one patients with clinically deep 2nd and 3rd degree burns, treated with EDNX in two Belgian burn centers, were included in the registry for the first phase of the reimbursement process. The total success rate of the EDNX treatment was 95.1% (39/41). Over half of the burn wounds treated with NexoBrid^® (55.2%) did not require any additional surgical debridement or skin grafting. To obtain definitive reimbursement, an extra 16 patients were included. In this population, 51.4% did not require any surgical intervention. The total success rate of the EDNX debridement in this group was 100%. Based on an estimated market share of 12% and around 75 patients in the third year after final reimbursement, a market access consultant calculated that NexoBrid^® will realize yearly savings for the Belgian Healthcare budget of at least €30.000.

CONCLUSION

Based on the results of this Belgian registry study in combination with the yearly healthcare budget savings, the NIHDI granted a final reimbursement for EDNX treatment in adults, endorsed by the Minister of Health on November 5^th, 2019.

Bromelain, a Group of Pineapple Proteolytic Complex Enzymes (Ananas comosus) and Their Possible Therapeutic and Clinical Effects. A Summary

Bromelain is a complex combination of multiple endopeptidases of thiol and other compounds derived from the pineapple fruit, stem and/or root. Fruit bromelain and stem bromelain are produced completely distinctly and comprise unique compounds of enzymes, and the descriptor “Bromelain” originally referred in actuality to stem bromelain. Due to the efficacy of oral administration in the body, as a safe phytotherapeutic medication, bromelain was commonly suited for patients due to lack of compromise in its peptidase efficacy and the absence of undesired side effects. Various in vivo and in vitro studies have shown that they are anti-edematous, anti-inflammatory, anti-cancerous, anti-thrombotic, fibrinolytic, and facilitate the death of apoptotic cells. The pharmacological properties of bromelain are, in part, related to its arachidonate cascade modulation, inhibition of platelet aggregation, such as interference with malignant cell growth; anti-inflammatory action; fibrinolytic activity; skin debridement properties, and reduction of the severe effects of SARS-Cov-2. In this paper, we concentrated primarily on the potential of bromelain’s important characteristics and meditative and therapeutic effects, along with the possible mechanism of action.

Bromelain-based enzymatic debridement of chronic wounds: Results of a multicentre randomized controlled trial

Chronic wounds are estimated to affect over 6 million people annually in the United States with an estimated annual cost of $25 billion. Debridement represents a key step in their management and is considered a basic necessity to induce the functional process of tissue repair. However, there is an unmet need for an efficient rapid acting non-surgical debridement agent. Bromelain-based enzymatic debridement has been proven to provide an effective, selective and safe non-surgical debridement in deep burns. EscharEx (MediWound Ltd, Yavne, Israel), is a bromelain-based enzymatic debridement agent currently in development for chronic wounds. The aim of this study was to assess its safety and efficacy in chronic wounds. Seventy-three patients suffering from a lower extremity ulcer of diabetic/venous insufficiency/post-surgical/traumatic aetiology were enrolled in a multicentre, assessor blinded, randomized controlled trial. Patients were randomized to topical treatment by either EscharEx or its gel vehicle for up to 10 daily 4 hour applications, and then continued follow-up for up to 6 months. The EscharEx arm achieved a significantly higher incidence of complete debridement compared to the gel vehicle arm; 55 versus 29% (p = .047), thus meeting the primary endpoint of this study. The EscharEx and gel vehicle arms achieved similar reductions in wound area, non-viable tissue area and wound healing scores during the debridement period. There were no significant differences between the arms in the incidence of complete wound closure (41% in the EsxcharEx arm vs. 53% in the gel vehicle arm) and in the mean time to complete wound closure (70.0 ± 32.8 days in the EsxcharEx arm vs. 65.7 ± 38.4 days in gel vehicle arm). There were no significant safety issues and EscharEx demonstrated a favourable benefit to risk profile.

Nexobrid Treatment for Burn Injuries in Patients With Chronic Obstructive Pulmonary Disease and Home Oxygen Therapy

There is an increased risk for burn injuries associated with home oxygen therapy of patients with chronic obstructive pulmonary disease since 10 to 50 % of these patients continue to smoke. Enzymatic eschar removal of facial burns is gaining popularity but intubation of this specific patient group often leads to prolonged weaning and can require tracheostomy. This study dealt with the question if enzymatic debridement in these patients can also be performed in analgosedation. A selective review of the literature regarding burn trauma associated with home oxygen use in patients with COPD was performed, as well as a retrospective analysis of all patients with burn injuries associated with home oxygen use and chronic obstructive pulmonary disease that were admitted to the study clinic. In the literature 1746 patients with burns associated with home oxygen use are described, but none of them received enzymatic debridement. In this study seventeen patients were included. All three patients in this study with facial full-thickness burn injuries received enzymatic debridement. The mortality rate in this cohort was 17.6 % (3/17). Up to date, there is limited experience performing regional anesthesia debridement in patients with COPD. This is the first manuscript describing the use of enzymatic debridement in patients with COPD and home oxygen therapy. We could confirm other studies that intubation of these patients leads to prolonged ventilation hours and increases the probability for poor prognosis. Therefore, we described the treatment of enzymatic debridement in analgosedation without intubation.

Acute Management of Thermal Hand Burns in Adults: A 10-Year Review of the Literature

INTRODUCTION

Advances in the evidence base of acute thermal hand burns help to guide the management of these common injuries. The aim of this literature review was to evaluate recent evidence in the field over 10 years.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols methodology was used as a guide for this literature review. PubMed, MEDLINE, EMBASE, CINAHL, and Google Scholar were searched for English language articles related to hand burns published between 2009 and 2018 inclusive, and the Cochrane Library was reviewed. Exclusion criteria were as follows: participants younger than 18 years, scar or contracture management, rehabilitation, outcomes assessment, late reconstruction, and electrical or chemical burns.

RESULTS

An initial search retrieved 6493 articles, which was narrowed to 403 full-text articles that were reviewed independently by 3 of the authors and categorized. Of 202 included articles, there were 8 randomized controlled trials and 2 systematic reviews. Six evidence-based guidelines were reviewed. Referral of hand burns to specialist centers, use of telemedicine, early excision and grafting, and immediate static splintage have been recommended. Enzymatic debridement results in earlier intervention, more accurate burn assessment, preservation of vital tissue, and fewer skin grafts, and ideally requires regional anesthesia. Guidance on escharotomy emphasizes indication, technique and adequate intervention, and potential for enzymatic debridement. Inclusion of topical negative pressure, dermal regenerative templates, acellular dermal matrices, and noncellular skin substitutes in management has helped improve scar and functional outcomes.

DISCUSSION

The results of this literature review demonstrate that multiple national and international societies have published burns guidelines during the decade studied, with aspects directly relevant to hand burns, including the International Society for Burn Injuries guidelines. There are opportunities for evidence-based quality improvement across the field of hand burns in many centers.

CONCLUSIONS

More than 200 articles globally in 10 years outline advances in the understanding of acute management of thermal hand burns. Incorporating the evidence base into practice may facilitate optimization of triage referral pathways and acute management for hand burns.

Concepts in Early Reconstruction of the Burned Hand

BACKGROUND

Early reconstruction of burn sequelae of the hand can be challenging owing to high goals for functional and aesthetic outcome. A variety of reconstructive procedures with ascending levels of complexity exists and warrants careful indication.

METHODS

In this case series, the main reconstructive techniques for reconstruction of burn defects of the hand are described, illustrated, and discussed: split thickness skin grafting (STSG) with fibrin glue, dermal matrices with STSG, distant random pattern (abdominal bridge) flap, distant pedicled flap (superficial circumflex iliac artery flap), and free microvascular tissue transfer (anterolateral thigh flap). An algorithm for decision making in the reconstructive process is proposed.

RESULTS

Split thickness skin grafting provides sufficient coverage for partial thickness defects without exposure of functional structures; fixation with fibrin glue avoids unnecessary stapling. Dermal matrices under STSG provide vascularized granulation tissue on full thickness defects and can be used as salvage procedure on functional structures. Distant random pattern or pedicled flaps provide sufficient coverage of large full thickness defects with exposed functional structures but pose some challenges regarding patient compliance and immobilization. Free tissue transfer allows tailored reconstruction of large full thickness defects with exposed functional structures and can be safely and feasibly performed. Secondary and tertiary procedures are needed with more complex techniques; if applied correctly and consequently, all methods can yield favorable functional and aesthetic outcomes.

CONCLUSIONS

Reconstruction of the burned hand may require a broad armamentarium of surgical techniques with different levels of complexity, versatility, and applicability. Excellent results can be achieved with the right procedure for the right patient.

Overview of in situ gelling injectable hydrogels for diabetic wounds

Diabetes mellitus (DM) is an endocrine disorder that causes increased blood glucose than usual due to insulin impairment. In DM, several complications arise in which diabetic wound (DW) is the most devastating complication. About 25% of patients with DM expected to develop DWs in their lifetime and undergo limb amputations. Even though several treatments such as surgery, debridement, wound dressings, advanced therapies were available, the overall conclusion has been that with very few exceptions, patients still suffer from limitations like pain, frequent dress changing, high rates of failure, and cost involvement. Further, the treatments involving the delivery of therapeutic agents in treating DWs have limited success due to abnormal levels of proteases in the DW environment. In this backdrop, in situ gelling injectable hydrogels have gained special attention due to their easy encapsulation of therapeutic medications and prolonged release, filling the wound defect areas, ease of handling, and minimally invasive surgical procedures. Though the in situ gelling injectable hydrogels are developed a couple of decades ago, their use for treating DW has not yet been explored thoroughly. Thus, in this review, we have covered the sequential events of DW healing, pathophysiology, current treatments, and its limitations, along with a particular emphasis on the mechanism of action of these in situ gelling injectable hydrogels treating DWs.

Enzymatic debridement for burn wound care: Interrater-reliability and impact of experience in post-intervention therapy decision

INTRODUCTION

Enzymatic debridement (ED) has become a reliable tool for eschar removal. Although ED application is simple, wound bed evaluation and therapy decision post-intervention are prone to subjectivity and failure. Experience in ED might be the key, but this has not been proven yet. Aim of this study was to assess interrater reliability (IR) in post-intervention wound bed evaluation and therapy decision as well as the impact of experience. In addition, the authors introduce video assessment as a valuable tool for post-ED decision making and education.

MATERIAL AND METHODS

A video-based survey was conducted among physicians with various experience in ED. The survey involved multiple choice and 5-point Likert scale questions about professional status, experience in ED, confidence in post-ED wound bed evaluation and therapy decision. Subsequently, videos of 15 mixed pattern to full thickness burns immediately after removal of the enzyme complex were demonstrated. Participants were asked for evaluation of each burn wound, including bleeding pattern and consequent therapy decision. IR ≥80% was considered as a consensus. Responses were stratified according to participants' experience in applying ED (<10; 10-19; 20-49; ≥50 applications). IR was assessed by Chi^2-test (raw agreement (RA); ≥80% was considered as a consensus) and by Krippendorff's Alpha-test. In addition, expert consensus for therapy decision was compared to the actual clinical course of each shown patient. Last, participants were asked for their opinion on video as an assessment tool for post-ED wound bed evaluation, decision making and training.

RESULTS

31 physicians from 11 burn centers participated in the survey. Overall consensus (RA≥80%) in post-ED wound bed evaluation and therapy decision was achieved in 20 and 40%, respectively. Krippendorff's Alpha are given by 0.32 (95% CI: 0.15,0.49) and 0.31 (95% CI: 0.16,0.47), respectively. Subgroup analysis revealed that physicians with high experience in ED achieved significantly more consensus in post-intervention wound bed evaluation and therapy decision compared to physicians with moderate experience (60% vs. 13.3%; p=0.02 and 86.7 vs. 33.3%; p=0.04, respectively). Video analysis was considered a feasible (90.3%) and beneficial (93.5%) tool for post-intervention wound bed evaluation and therapy decision as well as useful for training purposes (100%).

CONCLUSION

Reliability of wound bed evaluation and therapy decision after ED depends on the experience of the rating physician. Video analysis is deemed to be a valuable tool for ED evaluation, decision making and user training.

Historical Perspectives on the Development of Current Standards of Care for Enzymatic Debridement

Background and Objective: The use of plant-based products for burn treatment dates back to 1600 BC. Enzymatic debridement, which can be achieved as non-surgical or conservative debridement, has recently gained increasing attention. Several reviews have been published thus far. However, there has been no historical article including the achievements of the last 20 years, and this is the first review to present the achievements made in the field of enzymatic debridement in the last 20 years. This study aimed to present a historical overview of the development of enzymatic debridement until the present day. Methods: Enzymes from bacteria and plants were initially used for full-thickness burn treatment; however, they did not gain attention. Papain-derived products were the first plant-based products used for enzymatic debridement. Sutilains gained broad use in the 70s and 80s but came off market in the 1990s. Bromelain has been used for burn treatment owing to its strong debriding properties. NexoBrid^™ is used as a minimally invasive approach for enzymatic debridement of deep dermal burns. However, its use has been limited due to commercially available bromelain and the presence of four distinct cysteine proteinases. NexoBrid^™ involves faster eschar removal together with reduced blood loss, leading to improved long-term outcomes. However, research on nonoperative enzymatic debridement of burns has taken decades and is still ongoing. Results: Overall, the results of our study indicate that necrectomy, which has been used for a long time, remains the standard of care for burns. However, enzymatic debridement has several advantages, such as faster eschar removal, reduced blood loss, and reduced need for skin grafting, especially in cases of facial and hand burns. Enzymatic debridement cannot replace surgical intervention, as the enzyme only works on the surface of the eschar. Enzymatic debridement is not recommended in the early phase of scald burns. Conclusions: Enzymatic debridement has become an integral part of burn therapy and the standard of care in specific burn centers.

Early experiences using bromelain-based enzymatic debridement in a tertiary burns centre in the United Kingdom: A retrospective case series review

BACKGROUND

The modern ethos of burn care requires a holistic approach that helps patients to not only survive but also maintain a good quality of life. Bromelain-based enzymatic debridement with Nexobrid™ (NXB) has been shown to selectively debride burnt tissue and allow dermal preservation, which has the potential to reduce surgical burden and improve scarring. In this study, early experience with the use of Nexobrid™ at a tertiary burns centre between July 2016 and December 2019 is presented. In particular, the study assessed whether NXB had changed the acute care delivered to this cohort.

METHODS

A retrospective analysis of the patients' records was performed. Results were analysed and presented in the context of current literature.

RESULTS

Twenty adult patients (17 male, 3 female) underwent enzymatic debridement with NXB. Median age was 42.5 years. Mean total burn surface area (TBSA) on admission was 20%. Twelve patients were admitted to the intensive care unit, and eight were admitted to the adult burns ward. Mean TBSA treated with NXB was 8.2%, usually within 24 h of admission (mean). All patients had anaesthetist-led analgesia. NXB debridement was successful in 55% of patients, obviating the need for escharotomy in some patients. Sixty percent of all patients required further surgery, and 80% of facial burns treated with NXB required further surgery. Inotrope support was associated with NXB failure (p = 0.015). Mean length of stay was 29 days.

DISCUSSION

Current evidence, including our own findings, cannot justify replacing the current surgical standard of care with NXB, but it certainly solidifies enzymatic debridement as a useful adjunct that should form part of the modern burn surgeon's armamentarium.

Patient-reported scar quality of donor-sites following split-skin grafting in burn patients: Long-term results of a prospective cohort study

BACKGROUND

Skin grafting is the current gold standard for treatment of deeper burns. How patients appraise the donor-site scar is poorly investigated. The aim of this study was to evaluate long-term patient-reported quality of donor-site scars after split skin grafting and identify possible predictors.

METHODS

A prospective cohort study was conducted. Patients were included in a Dutch burn centre during one year. Patient-reported quality of donor-site scars and their worst burn scar was assessed at 12 months using the Patient and Observer Scar Assessment Scale (POSAS). Mixed model analyses were used to identify predictors of scar quality.

RESULTS

This study included 115 donor-site scars of 72 patients with a mean TBSA burned of 11.2%. The vast majority of the donor-site scars (84.4%) were rated as having at least minor differences with normal skin (POSAS item score ≥2) on one or more scar characteristics and the overall opinion on 80.9% of the donor-site scars was that they deviated from normal skin 12 months after surgery. The overall opinion on the donor-site scar was 3.2 ± 2.1 vs. 5.1 ± 2.4 on the burn scar. A younger age, female gender, a darker skin type, and location on the lower leg were predictors of reduced donor-site scar quality. In addition, time to re-epithelization was associated with scar quality.

CONCLUSION

This study provided new insights in long-term scar quality of donor-sites. Donor-site scars differed from normal skin in a large part of the population 12 months after surgery. Results of this study can be used to inform patients on the long-term outcomes of their scars and to tailor preventive or therapeutic treatment options.

Optimierung der chirurgischen Behandlung Brandverletzter: Auszüge aus der fachübergreifenden S2k-Leitlinie „Behandlung thermischer Verletzungen des Erwachsenen“

Hintergrund Trotz Brandschutzmaßnahmen und Aufklärung erleiden ca. 0,5 Millionen Menschen pro Jahr in Deutschland Verbrennungen. Im Jahr 2018 mussten fast 2000 Schwerstbrandverletzte in deutschen Verbrennungszentren behandelt werden. Brandverletzungen stellen eine schwerwiegende Erkrankung mit hoher Mortalität und langfristigen Folgen für den Patienten dar.

Methodik und Ergebnisse Ziel dieses Übersichtsartikels ist es, eine Zusammenfassung der derzeit gültigen Leitlinie zur Behandlung von Verbrennungen im Erwachsenenalter (https://www.awmf.org/leitlinien/detail/ll/044–001.html) zu präsentieren, wobei der Fokus auf folgenden Aspekten liegt: 1. der Akutbehandlung der Brandwunde am Unfallort, 2. der Entscheidungsfindung zur Verlegung in ein Brandverletztenzentrum, 3. der chirurgischen Wundversorgung mit Debridement und Hauttransplantation und 4. der Nachsorge. Die S2k-Leitlinie basiert auf aktueller Literatur und dem Konsens von 11 an der Behandlung Brandverletzter beteiligter Fachgesellschaften.

Zusammenfassung Dieser Übersichtsartikel enthält gewichtete Empfehlungen zur Behandlung von Brandwunden erwachsener Patienten in Deutschland. Der Artikel soll Ärzten und medizinischem Personal in der Akutsituation vor Ort und in der Klinik die Entscheidung über die notwendige Behandlung erleichtern. Hiermit soll die Behandlungsqualität für Patienten verbessert werden.

Clinical Value of Debriding Enzymes as an Adjunct to Standard Early Surgical Excision in Human Burns: A Systematic Review

Burns are a significant public health burden worldwide. In addition to those who die, millions remain with life-threatening deformities and disabilities resulting in stigma and rejection. Surgical excision is currently the standard of care for removing necrotic tissues in burn wounds to prepare the wound bed for grafting or enhancing the healing process. However, there is a growing interest on enzymatic debridement as an adjunct therapy in burn wounds. The aim of this study was to investigate clinical trials using debriding agents for burn wound in humans in a systematic review. This was a systematic review of electronic databases including CINAHL, PubMed, Ovid Medline, Web of Science, Google Scholar, and Embase from January 1969 to February 2019. The study protocol was registered in PROSPERO registry. The following keywords were searched: "burn wounds", "enzymatic debridement", "papain", "papain-urea", "pine apple", "Bromelain", "collagenases", "Nexobrid", "Debrase", "Debridase", "Actinidia deliciosa", "Sutilains", "Debrace", "piruvat acid". Those studies fulfilling the inclusion and exclusion criteria with low score of bias based on Cochrane Bias Tool were reviewed. Sixteen investigations fulfilled our inclusion criteria to be reviewed. Six, seven, and three clinical trials on humans were found regarding collagenase, bromelain, and miscellaneous agents. Collagenase has been reported to be effective in burns below 25% of TBSA, especially in outpatients' clinics. However, Nexobrid has been shown to be effective in deep burns and decreases the percentage of graft without significant adverse effects. There was not enough evidence supporting the clinical values of Papain, Sutilains, Urea, etc. Surgical excision still remains the standard of care for burn wounds debridement. However, enzymatic debridement, especially Bromelain might help to reduce sessions for surgical debridement or area under graft as an adjunct treatment. Despite the fact, more studies with larger sample sizes and with less conflicts of interest are needed to clearly elucidate the exact role of Bromelain.

[Implementation of treatment by enzymatic debridement in burns: results of an interprofessional German-speaking expert workshop]

INTRODUCTION

 Since its introduction in 2013 Bromelain-based Enzymatic Debridement (ED) is increasingly used in burn centers. Published evidence shows its efficiency in eschar removal as well as a superiority in blood loss and necessity of further surgical procedures compared to standard-of-care. While the procedure is safe and shows reliable results in experienced hands, some practical and logistical issues must be challenged that are not described sufficiently in available literature.

METHOD

 A multi-professional panel, consisting of experienced users of ED from German-speaking burn units has been invited to an expert workshop. Topics concerning indication, definition of treatment pathways, practical issues, post-treatment and handling of complications have been coordinated in advance to allow discussion during the workshop.

RESULTS

 To each topic practical recommendations were developed and consented. Summarizing key messages have been additionally highlighted. They aim on helping to achieve optimal results after establishing the technique by new users as well as optimizing results by experienced users. Amongst others, the resulting recommendations deal with indications for ED beyond the classic domain, different treatment pathways depending on burn depth and primary result after ED with adapted post-treatment, management of treatment failure and implementation of infrastructural conditions.

DISCUSSION

 While efficiency of ED as well as superiority in some aspects of treatment of burn wounds could be shown in available literature, user-oriented recommendations for practical implementation are scarce. Although the recommendations and experts opinions published here are only partly evidenced based, they are still based on the pooled experienced of the panelists that easily outnumbers the cases published in literature so far and allow valuable support for a successful implementation of the technique.

Safety of enzymatic debridement in extensive burns larger than 15% total body surface area

OBJECTIVES

Bromelain-based enzymatic debridement has emerged as an alternative to surgical eschar removal. Indications include partial thickness, mixed pattern, and full-thickness burns. Enzymatic debridement has been approved by the European Medicines Agency for treating burn wounds affecting <15% total body surface area (TBSA). Data and evidence for the treatment of areas >15% TBSA in one session is scarce. The aim of this retrospective study was to retrospectively analyze off-label use of enzymatic debridement in a single burn center for large TBSA burns.

METHODS

Between 01/2017 and 12/2018, 59 patients with partial- to full-thickness burns underwent enzymatic debridement in a single center study. Patients were categorized into two groups: the regular use group with a treated area less than 15% TBSA and the off-label group (OG) with larger TBSA debrided in one session. Treatment was evaluated for systemic inflammatory reaction, bleeding, hemodynamic instability and electrolyte shifts.

RESULTS

In total, 49 patients were treated in the regular use group with a median application area of 6% (IQR 2.5-9.5) and 10 patients were treated in the off-label group with a median application area of 18% (IQR 15-19) TBSA. We found no significant differences regarding blood pressure, body temperature or hemodynamic stability during and after enzymatic debridement. No treatment-related serious adverse events were observed in either group. Catecholamine use was similar in both groups. No differences in leukocyte counts, CRP, PCT and lactate prior to application and during the following three days were observed. Sodium, potassium, chloride and phosphate levels did not differ. We found no evidence of an electrolyte shift. Survival was 49 of 49 patients (100%) in the RG and 7 of 10 patients (70%) in the OG (p = 0.004).

CONCLUSION

Enzymatic debridement did not result in any expected or unexpected side effects in the patient groups investigated. These preliminary results indicate the potential safety of bromelain-based enzymatic debridementin the treatment of burns greater than 15% TBSA.