Wound Eschar Research Articles

An In Vitro Artificial Wound Slough-Biofilm Model Developed for Evaluating a Novel Antibiofilm Technology.

Eschar and slough in wounds serve as a reservoir for microorganisms and biofilms, damaged/devitalised cells, and inflammatory chemokines/cytokines, which work to initiate and prolong persistent inflammation and increase the risk of infection. Biofilm-related inflammation and infections are considered to be highly prevalent in acute wounds and chronic wounds. As slough is known to harbour biofilms, measuring the efficacy of antimicrobials in killing microbes both within and under slough is warranted. This highlights the need for more clinically relevant wound biofilm models to address this significant clinical need. Consequently, in this study, we developed an in vitro artificial wound slough (AWS) biofilm model produced by forming a biofilm below a layer of AWS, the latter of which was composed of the main protein components reported in wound eschar and slough, namely collagen, elastin, and fibrin. The model was employed to investigate the antibiofilm and antibacterial efficacy of a new patented smart next-generation antibiofilm technology composed of silver-zinc EDTA complexes and designed as a family of multifunctional metal complexes referred to as MMCs, in a liquid format, and to determine both the performance and penetration through AWS to control and manage biofilms. The results demonstrated the ability of the AWS-biofilm model to be employed for the evaluation of the efficacy of a new antibiofilm and antimicrobial next-generation smart technology. The results also demonstrated the potential for the proprietary EDTA multifunctional metal complexes to be used for the disruption of biofilms, such as those that form in chronic wounds.

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.

Early wound excision within three days decreases risks of wound infection and death in burned patients

IntroductionIn lieu of limited studies on the timing of burn wound eschar excision for burns, a more comprehensive analysis is indicated to determine the effects of early wound excision following burns. This study aims to address the outcomes of early wound excision in burn patients. MethodsData collection were from TriNetX research database. Three groups of burn patients were stratified by the number of days in which they received burn wound excision within 14 days of injury. Five outcomes were observed: death, wound infection, sepsis, myocardial contractile dysfunction, and blood transfusion. Risk and incidence of various health outcomes were compared between the groups after propensity-matching age, sex, ethnicity, race and burn size using a z-test with p < 0.05 considered significant. ResultsWe identified 6158 burn patients with wound excision within 14 days of injury, the majority of whom (60.1%) received burn wound excision between 0 and 3 days after burn. 72.5% of patients had burns covering less than 20% of total body surface area. After propensity matching, we found a significantly lower risk of mortality in those who received burn wound excision within the first three days (3.84%) as compared to 8–14 days after burn (6.09%) (p < 0.05). Moreover, we found a decreased risk of wound infection in patients with burn wound excision within 0–3 days (37.84%) compared to those 4–7 days (42.48%) (p < 0.05). No statistical difference was detected in propensity-matched groups for myocardial contractile dysfunction, blood transfusion, or sepsis. In addition, the risk of hypertrophic scaring significantly decreased when wound excision was performed within 0–3 days (22% within 0–3 days, 28% within 4–7 days, p < 0.05). ConclusionBurn wound excision within 3 days of injury is beneficial when comparing to later treatment between 4 and 14 days, which results in a significantly lowered risk of mortality and infection in burn patient.

The Use of Laser Doppler Imaging in Nitric Acid Burns: A Case Report and Literature Review.

Laser Doppler Imaging (LDI) technology has been validated to assess thermal burn depth by predicting wound healing potential. However, there is no clear evidence for its use in chemical burns. We present a case of an 8% total burn surface area (TBSA) nitric-acid burn following an industrial accident, in an otherwise healthy 36-year-old man. LDI assessment was suggestive of poor healing potential of >21 days, warranting surgical management. However, conservative management was opted for based on clinical assessment as the wound eschar appeared thin and more consistent with epithelial staining. Patient follow-up confirmed a total burn healing time of two months, suggesting that the LDI assessment was accurate. A comprehensive literature review was performed using the MEDLINE (PubMed) database to identify animal or clinical studies evaluating the efficacy of LDI in chemical burns. A qualitative synthesis of our findings is presented. We identified two experimental studies in porcine models with sulphur mustard burns, each confirming the accuracy of LDI assessment when compared to the histopathology findings. Limited experimental animal studies on the use of LDI suggest similar validity in chemical burns, and this correlates with the clinical outcome in this case. However, this alone is insufficient to prove its validity and define its role in the assessment of chemical burns. Clinical trials are required to further assess and define the parameters of LDI use and efficacy in this context.

Fluorimetric ex vivo quantification of protease debriding efficacy on natural substrate.

Debridement is the process of removal of necrotic and infected tissue to clean a wound or burn and expedite healing. Proteases such as papain, bromelain, and collagenase that promote debridement by degrading proteins in the dead tissue are in use today. However, the only method to measure debriding efficacy in vitro is the fluorescent monitoring of the digestion of an Artificial Wound Eschar (AWE) substrate. This AWE substrate contains a pellet of only three eschar matrix proteins collagen, elastin, and fibrin which do not account for the complexity and the composition of necrotic tissue. Here, we describe an ex vivo method using dry necrotic full thickness human skin and ortho-phthalaldehyde (OPA), a molecule commonly used for sensitive fluorimetric protein detection to monitor debridement activity. We advocate this simple yet sensitive approach to detect debridement efficacy that can readily be used commercially to benchmark products prior to in vivo testing.

Protease levels are significantly altered in pediatric burn wounds

Burn wounds contain high levels of protease activity due to the need to remodel the damaged extracellular matrix proteins. While necessary, excessive protease activity can lead to improper wound healing and is associated with increased contraction and fibrosis. No studies to date have investigated the expression changes of all the collagenases and elastases in burn wounds. The present study compares gene expression changes and changes in collagenase and elastase activity between burn wound eschar and normal skin in a pediatric population. Deidentified pediatric tissues were used for these experiments. Burn wound tissue was excised as part of normal standard care within a week from injury; normal skin was removed during elective plastic surgery procedures. RNA-sequencing was performed and significant results were confirmed with qRT-PCR. Activity assays showed a significant increase in both collagenase and elastase activity in the burn wound tissue compared to the normal skin. Western blotting and substrate zymography of tissue homogenates evaluated the results at the protein levels. Four elastases and three collagenases were determined to be significantly upregulated in the wound tissues by both RNA-sequencing and qRT-PCR. Cathepsin V was the only protease that was significantly downregulated. All but one metalloproteinase studied was significantly upregulated. None of the serine proteases were significantly altered in the wound tissues. In conclusion, matrix metalloproteinases appear to be the most highly elevated proteases after a pediatric burn wound injury, at least within the first 3–7 days. The data warrant further investigation into the effects of MMPs on burn wound healing.

The Immune Response to Chronic Pseudomonas aeruginosa Wound Infection in Immunocompetent Mice.

Objective: Our goal was to develop a chronic wound model in mice that avoids implantation of foreign material or impaired immunity and to use this to characterize the local and systemic immune response associated with Pseudomonas aeruginosa infection. Approach: We generated bilateral full-thickness dermal wounds in healthy 10-12-week-old C57Bl6 mice. We waited 24 h to inoculate the developing wound eschar at these sites. We performed careful titration experiments with luminescent strains of P. aeruginosa to identify bacterial inoculation concentrations that consistently established stable infections in these animals. We performed flow cytometry-based immunophenotyping of immune cell infiltrates at the wound site, spleen, and draining lymph nodes over time. Finally, we compared inflammatory responses seen in wound inoculation with planktonic bacteria, preformed biofilm, and heat-killed (HK) P. aeruginosa. Results: Using this delayed inoculation model and 7.5 ± 2.5 × 102 CFU/mL of PAO1 we consistently established stable infections that lasted at 10 days in duration. During early infection, we detected a strong upregulation of inflammatory cytokines and neutrophil infiltration at the wound site, while natural killer (NK) cells and dendritic cells (DCs) were reduced. At the systemic level, only plasmacytoid DCs were increased early in infection. During later stages, there was systemic upregulation of B cells, T cells, and macrophages, whereas NK cells and interferon killer DCs were reduced. Infections with P. aeruginosa biofilms were not more virulent than infections with planktonic P. aeruginosa, whereas treatment with HK P. aeruginosa only induces a short-term inflammatory state. Innovation: We describe a versatile wound model of chronic P. aeruginosa infection that lasts 10 days without causing sepsis or other excessive morbidity. Conclusion: This model may facilitate the study of chronic wound infections in immunocompetent mice. Our findings also highlight the induction of early innate immune cell populations during P. aeruginosa infection.

Honey-Based Salve and Burdock Leaf Dressings as an Alternative to Surgical Debridement of a Traumatic Wound Eschar.

Objective: Nonviable necrotic eschar is an impedance to wound healing and can ultimately lead to failure of soft tissue coverage in traumatic or high-risk wounds. Topical therapeutic agents can provide a less invasive management alternative to surgical debridement of eschar.Approach: The case of a 40-year-old male with a traumatic right lower extremity amputation complicated by surgical incision ischemic eschar formation is reported. Honey-based salve with burdock leaf dressings was used to noninvasively manage eschar extending over the incision site. Images were obtained for 5 months of follow-up.Results: Five-month follow-up demonstrated complete resolution of eschar and re-epithelialization of skin in the affected region.Innovation: Honey-based salve with burdock leaf dressings shows promise for enhancing healing outcomes in traumatic wounds that develop nonviable eschar.Conclusion: Surgical debridement of an amputation stump with large ischemic eschar was avoided with the use of honey-based salve with burdock leaf dressings.

Stem Cells in Burn Eschar

This study compares mesenchymal cells isolated from excised burn wound eschar with adipose-derived stem cells (ASCs) and dermal fibroblasts in their ability to conform to the requirements for multipotent mesenchymal stem cells (MSCs). A population of multipotent stem cells in burn eschar could be an interesting resource for tissue engineering approaches to heal burn wounds. Cells from burn eschar, dermis, and adipose tissue were assessed for relevant CD marker profiles using flow cytometry and for their trilineage differentiation ability in adipogenic, osteogenic, and chondrogenic conditions. Although the different cell types did not differ significantly in their CD marker expression, the eschar-derived cells and ASCs readily differentiated into adipocytes, osteoblasts, and chondrocytes, while dermal fibroblasts only exhibited some chondrogenic potential. We conclude that the eschar-derived mesenchymal cells represent a population of multipotent stem cells. The origin of the cells from burn eschar remains unclear, but it is likely they represent a population of adult stem cells mobilized from other parts of the body in response to the burn injury. Their resemblance to ASCs could also be cause for speculation that in deep burns the subcutaneous adipose tissue might be an important stem cell source for the healing wound.

PH in the Bacteria-Contaminated Wound and Its Impact on Clostridium histolyticum Collagenase Activity

We sought to understand the influence of pH on Clostridium collagenase activity, using both in vitro and in vivo, and to understand the influence of bacterial contamination on pH in vivo. Artificial wound eschar was used for the assessment of debridement efficacy in vitro and the wound fluid of a contaminated pig wound model was used for examining pH during healing using in vivo techniques. We used a collagen-based artificial wound eschar to test collagenase activity in the collagenase product under various pH conditions. We evaluated bacterial contaminated wounds, using a pig wound model with a bacterial load including Pseudomonas aeruginosa, coagulase-negative staphylococci, and Fusobacterium sp to track the pH of wounds in relation to bacterial load. The pH levels in the wound fluid were all above neutral. They varied from 9.2 on day 1 to 8.3 on day 10. Collagenase achieved its highest activity around a pH of 8.5 when tested in Tris-buffered saline. Using artificial wound eschar, the optimal pH range for C collagenase was determined to be more than a pH of 6. The total initial microbial load (day 0) was higher than levels at any other time during the study. The levels of P aeruginosa began to decrease on day 1, but by day 4 the total pseudomonas population had rebounded to near day 0 levels. This was followed by a distinct decrease and by day 21 levels were lower than those on day 0. The coagulase negative staphylococci (CNS) population behaved differently than the pseudomonas population, decreasing and remaining decreased relative to day 0 through day 14. However, by day 21 the CNS population had increased to near day 0 levels. This greatly influenced the increase in total bioburden by day 21, indicating that it was primarily due to the increase in CNS. The data demonstrate that wound pH in a model of contaminated pig wounds is alkaline during the first 10 days of healing. As healing progresses, pH decreases with no significant change in the level of bacterial bioburden. C collagenase exhibited robust activity in the pH range found in this contaminated pig wound model, suggesting it can effectively debride necrotic tissue in the environment found in most chronic wounds in humans.

Maggot chymotrypsin I from Lucilia sericata is resistant to endogenous wound protease inhibitors

A chymotrypsin found in the secretions of Lucilia sericata and manufactured as a recombinant enzyme degrades chronic wound eschar ex vivo. To characterize the inhibition profile of the L. sericata recombinant chymotrypsin I. Activity of recombinant chymotrypsin I and its sensitivity to endogenous inhibitors were determined enzymatically using the fluorogenic substrate succinyl-alanyl-alanyl-prolyl-phenylalanyl-aminomethyl coumarin. We report the presence of high concentrations of two endogenous inhibitors, α1-antichymotrypsin and α1-antitrypsin, in wound eschar and a trace of a third, α2-macroglobulin, with the potential to inhibit this debridement process. However, the addition of a soluble and inhibitor-containing extract of chronic wound eschar to chymotrypsin I did not affect activity of the enzyme, neither did the addition of purified native α1-antichymotrypsin or α1-antitrypsin, although chymotrypsin I was inhibited by α2-macroglobulin. Conversely, the mammalian equivalent, α-chymotrypsin, was inhibited by the purified native α1-antichymotrypsin, α1-antitrypsin and α2-macroglobulin and by the soluble extract of wound eschar. The data suggest that the maggot-derived chymotrypsin I is biochemically distinct from human α-chymotrypsin and the lack of inhibition by wound eschar suggests a means by which chymotrypsin I activity survives within the wound to contribute towards debridement during maggot biotherapy.

Study on the debridement efficacy of formulated enzymatic wound debriding agents by in vitro assessment using artificial wound eschar and by an in vivo pig model

An in vitro efficacy study using newly developed artificial wound eschar (AWE) substrate was conducted for assessing enzyme dose response. The AWE substrate is prepared by the enzymatic conversion of fibrinogen to fibrin in the presence of collagen, fibrin, and elastin to form an insoluble planar matrix. AWE substrate was placed on Franz Diffusion Cells for continuously monitoring the debridement progress. A parallel in vivo study was performed using pig thermal-burn wounds. Papain at concentrations of 200, 400, 800, and 1,600 U/mg was used as the model debriding enzyme for both studies. The data from the first 5 hours of the in vitro testing showed that debriding activity increased as the enzyme concentration increased. The histological results of the in vivo biopsy samples showed that enzyme doses above 800 and 1,600 U/mg successfully achieved debridement on day 8, while lower treatment groups still contained eschar tissue. Using the histological measurement results (wound depth score) a dose response that correlated to the in vitro assessment was found. Granulation tissue maturity and reepithelialization displayed correlation with the enzyme dose. Results indicate that AWE substrate can be used to predict debridement efficacy in vitro when correlation to the in vivo assessment is achieved.

The Nitric acid burn trauma of the skin

Nitric acid burn traumata often occur in the chemical industry. A few publications addressing this topic can be found in the medical database, and there are no reports about these traumata in children. A total of 24 patients, average 16.6 years of age, suffering from nitric acid traumata were treated. Wound with I degrees burns received open therapy with panthenol-containing creams. Wound of II degrees and higher were initially treated by irrigation with sterile isotonic saline solution and then by covering with silver-sulphadiazine dressing. Treatment was changed on the second day to fluid-absorbent foam bandages for superficial wounds (up to IIa degrees depth) and occlusive, antiseptic moist bandages in combination with enzymatic substances for IIb degrees -III degrees burns. After the delayed demarcation, necrectomy and mesh-graft transplantation were performed. All wounds healed adequately. Chemical burn traumata with nitric acid lead to specific yellow- to brown-stained wounds with slower accumulation of eschar and slower demarcation compared with thermal burns. Remaining wound eschar induced no systemic inflammation reaction. After demarcation, skin transplantation can be performed on the wounds, as is commonly done. The distinguishing feature of nitric-acid-induced chemical burns is the difficulty in differentiation and classification of burn depth. An immediate lavage should be followed by silver sulphadiazine treatment. Thereafter, fluid-absorbent foam bandages or occlusive, antiseptic moist bandages should be used according to the burn depth. Slow demarcation caused a delay in performing surgical treatments.

Enhancing drugs absorption through third-degree burn wound eschar

Antimicrobial therapy remains the most important method of wound infection treatment. Systemically administered antimicrobials may not achieve therapeutic levels in wound. On the other hand, some topically applied antimicrobials cannot penetrate eschar well enough. Therefore, an attempt has been made here to increase permeation of topically applied drugs through eschar using the so-called skin penetration enhancers. To perform this investigation, effects of different potential penetration enhancers on permeation of chlorhexidine, silver sulfadiazine and nitroglycerin through human third-degree burn eschar was evaluated. Results showed that water, glycerin, saline, sodium lauryl sulphate (SDS) and ethanol tend to reduce permeation of chlorhexidine through burn eschar. But, water, glycerin, hexane:ethanol and ethyl acetate:ethanol were able to increase permeation of silver sulfadiazine significantly by about 1.2–1.8 times, while saline, SDS and dimethyl sulfoxide were not able to change its permeation. Glycine showed 2.7 times enhancement toward permeation of nitroglycerin, followed by water, hexane:ethanol mixture, saline and SDS with enhancement ratios of 1.8–2.3. Urea, ethanol and citral were not able to increase permeation of nitroglycerin through eschar. This study shows that permeation of drugs through burn eschar can be improved by penetration enhancement including hydration; the effect depends on the nature of the penetrant.

Midline Posterior Approach to the Ankle and Hindfoot

The posterior approach to the ankle and hindfoot can be used for fixation of fractures, fusions, or osteotomies and is especially useful in patients with poor soft tissue anteriorly, medially, or laterally. However, a high rate of wound complications has been reported with standard posterolateral and posteromedial approaches. Because of local wound problems with the standard approaches, we have used a midline posterior approach and a longitudinal midline splitting of the Achilles tendon. This approach provides excellent exposure while minimizing wound healing complications. This approach provides dissection between angiosomes, which should optimize preservation of the blood supply to the skin flaps. We retrospectively evaluated wound healing in 33 consecutive patients who had surgery using the modified midline posterior approach. The mean age of the patients was 48 (range 16 to 83) years. The mean followup was 24 (range 12 to 73) months. Surgical procedures included ankle and pantalar arthrodeses (primary and revision), talectomies with tibiocalcaneal arthrodesis, repairs of fracture nonunions, reconstruction of a chronic Achilles rupture, and hardware removal with multiple debridements of chronic osteomyelitis. There were no instances of skin flap necrosis. One patient with diabetic neuropathic arthropathy developed a small superficial wound eschar that healed with dressing changes alone. Four patients developed deep infections; two of these had a history of deep infection and the other two had significant comorbidities. The modified midline posterior approach to the distal tibia, ankle, and hindfoot has a low primary wound complication rate without sacrificing exposure. This approach can be used for any procedure requiring posterior access to the distal tibia, ankle joint, or subtalar joint.

001 A Novel Model for the Assessment of Formulated Enzymatic Debriding Agents

In order to closely mimic the actual mechanism of wound debridement by an enzymatic debriding agent, a synthetic wound eschar substrate (SWES) has been developed. The SWES is prepared by the enzymatic conversion of fibrinogen to fibrin in the presence of fibrous bovine collagen and elastin, to form an insoluble planar matrix composed of the three major proteins present in wound eschar. Each of the proteinaceous components is uniquely labeled prior to formation of SWES with different dye, and the debridement test is conducted using a Franz Diffusion System. The debriding agent is applied to the SWES mounted on the donor compartment of the cell, and the digested hydrolysate containing dye‐labeled peptide fragments is sampled from the receptor compartment. Accordingly, the progress of digestion is obtained in real time. Since the three proteins are labeled with spectrally distinct dyes, data on the hydrolysis of the substrates can be collected simultaneously. This method facilitates the testing of formulated debriding products in a manner that closely mimics application to a wound and provides a powerful tool for the evaluation of formulated enzymatic debriding agents.

The structure and composition of chronic wound eschar.

Wounds with a covering of eschar require debridement before optimal wound healing can proceed. There are several different methods available but these have been derived empirically with no direct evidence of the structure or composition of the tissue they are designed to remove, or of the potential autolytic mechanisms which are the targets for some of these treatments. The aim of this study therefore was to determine the composition of chronic wound eschar and hence identify potential targets for the induction of autolytic debridement. Chronic wound eschar was removed by surgical debridement and analysed using immunohistochemistry, polyacrylamide gel electrophoresis (PAGE) and gelatin zymography. Immunohistochemistry using antibodies specific for extracellular matrix (ECM) proteins revealed a definite tissue structure, consisting of many fibrous regions and fine fibrillar elements separated by areas of tissue which were of a more irregular and amorphous nature. An antibody specific for all leucocytes revealed the presence of leucocytes in the region of tissue closest to the wound bed. The presence of this leucocyte population correlated to elevated levels of gelatinase activity as identified by gelatin zymography. PAGE analysis identified various protein species in the range 3.5-60 kDa molecular weight. These data indicate that wound debridement is likely to require multiple enzyme specificities to degrade the eschar and that these enzymes may be supplied by inflammatory leucocytes infiltrating the eschar from the wound bed. The various protein species demonstrated by PAGE may represent ECM proteins, those with lower molecular weight possibly representing the degradation products of autolytic debridement.

Effect of vibriolysin, an enzymatic debriding agent, on healing of partial‐thickness burn wounds

Vibriolysin, a new agent for enzymatic debridement, was recently shown to rapidly and thoroughly hydrolyze burn wound eschar within full-thickness wounds. The safety of this agent and its subsequent effect on wound healing processes have yet to be established and are addressed in this study. Within the context of a porcine partial-thickness burn wound model, the enzyme was shown to digest desiccated eschar after two applications, whereas four applications of another enzymatic preparation were required. Computerized morphometric analysis of dermal and epidermal growth from histologic sections on wounds harvested at day 7 and 10 was used to assess wound healing. The data indicate that wounds treated with Vibriolysin exhibited significant dose-responsive stimulation of granulation tissue (neodermis) as compared with control treatment groups. Repeated protease applications did not convert partial-thickness burns to full-thickness wounds, and no adverse inflammatory responses were detected between 1 and 10 days. The results suggest that in addition to its documented efficacy in the debridement of burn eschar, Vibriolysin may have beneficial effects on dermal reparative events.

Preliminary evaluation of vibriolysin, a novel proteolytic enzyme composition suitable for the debridement of burn wound eschar.

Vibriolysin, a proteolytic enzyme secreted by the marine microorganism Vibrio proteolyticus, was evaluated for its efficacy as an enzymatic debridement agent. Initial in vitro experiments revealed that the protease readily hydrolyzed proteinaceous components of eschar (e.g., fibrin, elastin, and in particular, collagen). Enzyme selectivity towards the digestion of denatured proteins but not viable elements was demonstrated in vitro and in vivo by treatment of full-thickness burn wounds with a porcine model. The full-thickness wound eschar was rapidly hydrolyzed by a hydrophilic vibriolysin composition with a resultant wound bed that appeared pink and viable. Vibriolysin exhibited desirable properties heretofore not described for the enzymatic debridement agents, in particular, its selective hydrolysis of dead but not viable tissue, debridement in the absence of bleeding, compatibility with adjunct therapies, and its unique shelf-life stability in a hydrophilic composition at ambient temperature.

Antibiotic prophylaxis in patients undergoing burn wound excision.

Eleclive excision of burn wound eschar is frequently associated with transient bacteremias that may predispose to episodes of surgically induced sepsis. The need for parenteral administration of prophylactic antibiotics, often used in nonseptic burn patients undergoing early elective burn wound excision, was therefore evaluated. Sixty patients with 4% to 90% total body surface area (TBSA) burn undergoing elective burn wound excision [full- thickness eschareetomies and deep partial-thickness tangential excisions] were stratified on the basis of percent TBSB and divided into treated and untreated groups. Blood cultures were obtained preoperatively, intraoperatively, and postoperatively for temperature elevations greater than 38.5C. A positive intraoperative blood culture associated with a subsequent postoperative septic course was not identified in any patient with a burn of less than 60% TBSA, during either the initial or subsequent surgical procedures. These data show that antibiotic prophylaxis for early elective wound excision in nonseptic burn patients with less than 60% TBSB may be an unnecessary expense.