Management of burn wounds with prompt excision and immediate closure

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.

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.

The Association Between Burn Unit Census and Operative Intervention in a Resource-Limited Setting

INTRODUCTION

The relationship between hospital volume and outcomes remains unclear in the delivery of burn care in resource-limited settings, where demand often exceeds capacity. We sought to characterize the association between burn patient volume and the use of operative intervention at a tertiary burn unit in Malawi.

METHODS

This study examined patients admitted to Kamuzu Central Hospital located in Lilongwe, Malawi, over years 2011-2019. We described the association between the census at the time of admission and the use of operative intervention, as well as the time to operation. Patient census was defined as low (≤ 15 patients), medium (16-29 patients), and high (≥ 30 patients).

RESULTS

A total of 2484 patients were included. The mean daily burn unit census was 22.5 patients (SD 6.6) and varied significantly by season. For the medium and high census, the adjusted risk ratio of undergoing surgery was 0.79 (95% CI 0.64, 0.97) and 0.65 (95% CI 0.49, 0.85), respectively, adjusted for flame burn, age, %TBSA, and delayed presentation. At a low admission census, the adjusted mean time to operation was 17.2 days (95% CI 14.4, 20.1) compared to 28.3 days (95% CI 25.4, 31.2) at a high census.

CONCLUSIONS

In a resource-limited setting, an increasing mean daily census significantly reduced the use of operative intervention and increased time to operation, potentially increasing burn-associated morbidity. In order to improve the quality of burn care in similar environments, improved resource allocation during busier seasons and targeted burn prevention efforts are imperative.

Patients' satisfaction with anesthesia in enzymatic debridement from a surgical perspective

INTRODUCTION

Various clinical studies found that enzymatic debridement (EDNX) is superior to tangential excision after severe burns. The current study evaluates patients' satisfaction with pain management in EDNX with special respect to different anesthesia techniques.

METHODS

Between 2015 and 2016, all patients at a department of plastic surgery were asked to complete a German-wide validated pain questionnaire. In a retrospective study design, satisfaction with pain management was compared between the control group (diagnosis from the whole field of plastic surgery except burns) and the EDNX group (burns treated with EDNX only). Analgosedation, general, regional and local anesthesia were chosen for pain management.

RESULTS

In the control group 403 patients (153 females, 250 males, medium age 53 years) could be included The EDNX group included 88 patients (20 females, 68 males, medium age 38 years). The mean burn size was 5.3% TBSA. Between 0.5%-10.5% of the surface was treated with EDNX. EDNX patients could be treated under analgosedation and regional anesthesia, by topical anesthesia creme and without any anesthesia. They reported less pain during stress (p = 0.04) and were less frequently affected by motion (p = 0.024) and nausea (<0.001). However, they felt that they need more information about alternative anesthetic treatments (<0.001).

CONCLUSION

EDNX can be performed sufficiently either under analgosedation, regional or local anesthesia. Thus, side effects of general anesthesia can be reduced and treatment costs can be decreased. However, it was found that neither after topical anesthetic creme nor after hand block pain treatment was sufficient.

The effects of platelet rich plasma on healing of full thickness burns in swine

INTRODUCTION

Platelet rich plasma (PRP) is rich in growth factors and has been shown to improve healing in a variety of wounds. We determined the effects of PRP on healing and scarring in full thickness porcine burns with and without tangential excision and grafting (TEG).

METHODS

Standardized full thickness 5cm by 5cm burns were created on each of the backs and flanks of 10 anesthetized female pigs (25kg) using a validated model. The burns were created with a heating device that emits heat at a temperature of 400°C for a period of 30s. The burns were randomized to one of six treatments: no TEG or PRP, no TEG+PRP, early (day 2) TEG and no PRP, early TEG+PRP, late (day 14) TEG and no PRP, and late TEG+PRP. Tangential excision was performed down to viable tissue and autografts were 0.2mm thick. When used, a thin layer of autologous PRP was applied below the graft. All wounds were then treated with a topical antibiotic ointment 3 times weekly for 42 days. Digital images and full thickness biopsies were taken at 9, 11, 14, 18, 21, 28, 35 and 42days after injury to determine percentage reepithelialization, scar depth, and scar contraction. Tissue sections were stained with H&E and viewed by a dermatopathologist masked to treatment assignment.

RESULTS

There was no reduction in platelet and white blood cell concentrations in PRP and blood samples for the first 14days after-full thickness burns. A total of 120 burns were created on 10 animals evenly distributed between the six treatment groups. Burns undergoing early TEG reepithelialized fastest and with the thinnest scars followed by late TEG. Burns that did not undergo TEG had the slowest reepithelialization and greatest amount of scarring. Application of PRP had no additional effects on reepithelialization, scar depth, or scar contraction in any of the treatment groups.

CONCLUSIONS

Addition of PRP had similar effects on reepithelialization and scarring of full thickness porcine burns as standard topical antibiotic ointment regardless of whether the burns underwent excision or grafting or the timing of excision and grafting.

Natural actives for wound healing: A review

Nature has been a source of medicinal treatments for thousands of years, with the use of plants as prototypes for drug development and for the extraction of active compounds. Skin injuries occur regularly in everyday life, and the human skin has the ability to promote repair spontaneously under healthy conditions. However, some intrinsic and external factors may interfere with skins' natural ability, leading to nonhealing lesions and chronic wounds, which directly affect health and quality of life. Thus, attention should be given to this health problem, using an appropriated management when necessary. In this scenario, phytotherapy may be an option for cutaneous wound treatment, although further high-quality studies are needed to firmly establish the clinical efficacy of plants. This article reviews traditionally used natural actives for wound healing, highlighting their characteristics and mode of action.

On the horizon: research priorities in burns for the next decade

This review demonstrates that many advances have been made in burn care that have made dramatic differences in mortality, clinical outcomes, and quality of life in burn survivors; however, much work remains. In reality, the current standard of care is insufficient and we cannot be satisfied with the status quo. We must strive for the following goals: no deaths due to burn, no scarring, and no pain. These particular goals have only begun to be confronted.

Enzymatic debridement of large burn wounds with papain-urea: Is it safe?

INTRODUCTION

Enzymatic debridement is a method by which burn wounds can be prepared for coverage by skin grafts in patients presenting late. Many agents have been used in the past but none of them have been thoroughly evaluated. The present study was undertaken to assess the efficacy of Debridace, a commonly available debriding agent with papain and urea as its constituents.

MATERIAL AND METHODS

A prospective descriptive study design was used to evaluate our experience. Almost symmetrical areas of the burnt surface were assessed and used for comparison. On one half of the wound, Debridace was applied while on the other silver sulphadiazine was used. The primary end point of this study was the extent of the achieved debridement at the end of the study period. Secondary outcomes were the presence of adverse effects such as pain and fever. All patients with sepsis were excluded from the study.

RESULTS

The age of the subjects ranged from 9 to 80 years with an SD of 16. Large areas ranging from 5% to 20% body surface area with an SD of 4.27 were debrided by Debridace. Only two patients (3.33%) could complete the study. The rest of the recruited patients either had high fever (63.33%), excruciating pain (13.33%) or both (16.66%), which brought an end to enzymatic debridement.

CONCLUSION

Debridace, a papain-urea product, cannot be considered safe as an enzymatic debriding agent in its present form for use in major burn patients who present late with deep burn wounds that are large in size.

Properties and therapeutic application of bromelain: a review

Bromelain belongs to a group of protein digesting enzymes obtained commercially from the fruit or stem of pineapple. Fruit bromelain and stem bromelainare prepared differently and they contain different enzymatic composition. "Bromelain" refers usually to the "stem bromelain." Bromelain is a mixture of different thiol endopeptidases and other components like phosphatase, glucosidase, peroxidase, cellulase, escharase, and several protease inhibitors. In vitro and in vivo studies demonstrate that bromelain exhibits various fibrinolytic, antiedematous, antithrombotic, and anti-inflammatory activities. Bromelain is considerably absorbable in the body without losing its proteolytic activity and without producing any major side effects. Bromelain accounts for many therapeutic benefits like the treatment of angina pectoris, bronchitis, sinusitis, surgical trauma, and thrombophlebitis, debridement of wounds, and enhanced absorption of drugs, particularly antibiotics. It also relieves osteoarthritis, diarrhea, and various cardiovascular disorders. Bromelain also possesses some anticancerous activities and promotes apoptotic cell death. This paper reviews the important properties and therapeutic applications of bromelain, along with the possible mode of action.

Infection control in severely burned patients

In the last two decades, much progress has been made in the control of burn wound infection and nasocomial infections (NI) in severely burned patients. The continiually changing epidemiology is partially related to greater understanding of and improved techniques for burn patient management as well as effective hospital infection control measures. With the advent of antimicrobial chemotherapeutic agents, infection of the wound site is now not as common as, for example, urinary and blood stream infections. Universal application of early excision of burned tissues has made a substantial improvement in the control of wound-related infections in burns. Additionally, the development of new technologies in wound care have helped to decrease morbidity and mortality in severe burn victims. Many examples can be given of the successful control of wound infection, such as the application of an appropriate antibiotic solution to invasive wound infection sites with simultaneous vacuum-assisted closure, optimal preservation of viable tissues with waterjet debridement systems, edema and exudate controlling dressings impregnated with Ag (Silvercel, Aquacell-Ag). The burned patient is at high risk for NI. Invasive interventions including intravenous and urinary chateterization, and entubation pose a further risk of NIs. The use of newly designed antimicrobial impregnated chateters or silicone devices may help the control of infection in these immunocomprimised patients. Strict infection control practices (physical isolation in a private room, use of gloves and gowns during patient contact) and appropriate empirical antimicrobial therapy guided by laboratory surveillance culture as well as routine microbial burn wound culture are essential to help reduce the incidance of infections due to antibiotic resistant microorganisms.

Histological Assessment of Tangentially Excised Burn Eschars

BACKGROUND

The burn eschar serves as a medium for bacterial growth and a source of local and systemic infection. To prevent or minimize these complications, it is important to debride the eschar as early as possible.

OBJECTIVE

To identify the presence of viable skin within the excisions by examining tangentially excised burn eschars.

METHODS

A total of 146 samples of burned human tissue were removed during 54 routine sharp tangential excision procedures (using dermatomes). The samples were histologically examined to identify the relative thickness of the dead, intermediate and viable layers.

RESULTS

The mean (± SD) thickness of the excised samples was 1.7 ± 1.1 mm. The sacrificed viable tissue (mean thickness 0.7+0.8 mm) occupied 41.2% of the entire thickness of the excision. In 32 biopsies (21.8%; 95% CI 16.0 to 29.3), the excision did not reach viable skin. Only eight biopsies (5.4%; 95% CI 2.8 to 10.1) contained all of the necrotic tissue without removing viable tissue.

CONCLUSIONS

The thickness of a single tangentially excised layer of eschar is not much greater than the actual thickness of the entire skin and often contains viable tissue. Because surgical debridement is insufficiently selective, more selective means of debriding burn eschars should be explored.

Metabolic implications of severe burn injuries and their management: a systematic review of the literature

BACKGROUND

Severe burn patients are some of the most challenging critically ill patients, with an extreme state of physiologic stress and an overwhelming systemic metabolic response. A major component of severe burn injury is a hypermetabolic state associated with protein losses and a significant reduction of lean body mass. The second prominent component is hyperglycemia. Reversal of the hypermetabolic response by manipulating the patient's physiologic and biochemical environment through the administration of specific nutrients, growth factors, or other agents, often in pharmacologic doses, is emerging as an essential component of the state of the art in severe burn management. The present review aims at summarizing the new treatment modalities established to reduce the catabolic burden of severe burn injuries, for which there is some evidence-based support.

METHODS

A systematic review of the literature was conducted. Search tools included Elsevier ScienceDirect, EMBASE.com, Medline (OVID), MedlinePlus, and PubMed. Topics searched were Nutrition and Burns, Metabolic Response and Burns, Hypermetabolism and Burns, Hyperglycemia and Burns, and several more specific topics when indicated. With a focus on the most recently published articles, abstracts were reviewed and, when found relevant, were included as references. Full text articles, whenever available, were retrieved.

RESULTS

Many issues remain unanswered. Unfortunately, the present state of our knowledge does not allow the formulation of clear-cut guidelines. Only general trends can be outlined, and these will certainly have some practical applications but above all will dictate future research in the field.

Burns: what are the pharmacological treatment options?

BACKGROUND

Many advances have been made in the understanding and management of burn injury, dramatically increasing pharmacological decision options for burn care professionals. Since burn injury is so multi-faceted, these advances cross many injury processes, both acute and chronic.

OBJECTIVE

The purpose of this review was to highlight the advances and decision options across the entire scope of the burn injury process. The burn-related processes with the most significant pharmacological options of approved products are highlighted.

METHODS

The scope of the current research is the most pertinent literature, which has been summarized with the addition of a personal perspective.

RESULTS/CONCLUSIONS

Many advances over the past decade in multiple fields have made pharmacological options plentiful in burn care. That said, there are many problems for the burn patient which persist, making burn injury still the most severe form of trauma. These issues range from management of a catabolic state with involuntary weight loss in the critical burn to severe itching in the rehabilitating patient. There are also many more treatment options available today. Two key reasons stand out as the most prominent. One reason is the fact that burn care has become much more proactive, by searching out new approaches to solve old problems. Now the treatment approach is altering its focus on manipulating the course of a burn. Examples include the use of temporary skin substitutes in partial thickness or second degree burns, decreasing pain and increasing the healing rate. Another is the use of slow release silver dressing as the topical burn wound antimicrobial of choice, markedly reducing discomfort, the need for dressing changes and an overall decrease in infection. In larger, deeper burns, the approach has changed from the chronic management of an open burn wound to rapid excision and wound closure, eliminating the burn as a source of complications. In addition, there has been a very aggressive approach to controlling the profound hypermetabolic, catabolic response to burns, rather than simply treating the outcome of this predictable post-burn complication. Approaching psychosocial stress again by prevention rather than treatment of established problems is another example. The second reason for increased options and differences in management involves the mindset of those individuals taking care of burns. Tremendous differences in experience are involved in decision-making. Different opinions are based on the expertise and also the personal preferences of those managing the burn.

Management Outcome and Associated Factors in Burn Injuries With and Without Facial Involvement in a Nigerian Population

There is a high potential for the occurrence of burns in Nigeria, yet very little is known about factors that are associated with management outcomes (death/survivorship) in burns affecting facial or other body areas among Nigerian populations. This study aimed at determining patterns of occurrences of burn injuries with and without facial involvement and the factors that are associated with mortality. A standardized data-collection instrument was designed and used to extract relevant information about burn patients that were seen at the Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, Nigeria, between 1998 and 2003. During the study period, fuel-related flames constituted the leading type of agent in both facial (71.1%) and nonfacial involved burns (65.3%). There was no significant difference in the incidence of contracture and inhalation injury between burns with facial involvement and burns without facial involvement, but cases of facial involvement have significantly lower incidences of wound infections. No significant difference was seen in the incidence of mortality between burns with facial involvement (31.6 %) and burns without facial involvement (30.7%). Significant bivariate correlates for mortality were age, flame as the agent of burns, depth of the burns and wound infections. Two correlates remained significant in the multivariate analysis (binary logistic regression): BSA involved and wound infection.

Burn wound infections

Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. Significant thermal injuries induce a state of immunosuppression that predisposes burn patients to infectious complications. A current summary of the classifications of burn wound infections, including their diagnosis, treatment, and prevention, is given. Early excision of the eschar has substantially decreased the incidence of invasive burn wound infection and secondary sepsis, but most deaths in severely burn-injured patients are still due to burn wound sepsis or complications due to inhalation injury. Burn patients are also at risk for developing sepsis secondary to pneumonia, catheter-related infections, and suppurative thrombophlebitis. The introduction of silver-impregnated devices (e.g., central lines and Foley urinary catheters) may reduce the incidence of nosocomial infections due to prolonged placement of these devices. Improved outcomes for severely burned patients have been attributed to medical advances in fluid resuscitation, nutritional support, pulmonary and burn wound care, and infection control practices.

Burn wound infections

Burns are one of the most common and devastating forms of trauma. Patients with serious thermal injury require immediate specialized care in order to minimize morbidity and mortality. Significant thermal injuries induce a state of immunosuppression that predisposes burn patients to infectious complications. A current summary of the classifications of burn wound infections, including their diagnosis, treatment, and prevention, is given. Early excision of the eschar has substantially decreased the incidence of invasive burn wound infection and secondary sepsis, but most deaths in severely burn-injured patients are still due to burn wound sepsis or complications due to inhalation injury. Burn patients are also at risk for developing sepsis secondary to pneumonia, catheter-related infections, and suppurative thrombophlebitis. The introduction of silver-impregnated devices (e.g., central lines and Foley urinary catheters) may reduce the incidence of nosocomial infections due to prolonged placement of these devices. Improved outcomes for severely burned patients have been attributed to medical advances in fluid resuscitation, nutritional support, pulmonary and burn wound care, and infection control practices.

Early Excision of a Full-Thickness Burn Prevents Peripheral Nerve Conduction Deficits in Mice

BACKGROUND

A full-thickness 20 percent body surface area burn in mice produces a significant decrease in tibial motor nerve conduction velocity within 6 hours of the burn and in sensory conduction velocity within 7 days. This suggests that cutaneous burn injury produces a systemic response that affects peripheral motor and sensory nerve function at a distance from the burn site. The authors tested the hypothesis that burn wound excision either 30 minutes or 3 hours after burn would prevent neuropathy.

METHODS

A 20 percent body surface area third-degree burn was applied to the backs of anesthetized mice using procedures that followed National Institutes of Health guidelines. Motor nerve conduction velocity and sensory conduction velocity were determined in intact, anesthetized mice by percutaneous nerve stimulation. Burn wounds were excised and closed at 30 minutes or 3 hours after burn. Motor nerve conduction velocity and sensory conduction velocity were measured before burn and 1, 3, 7, 14, and 21 days after a burn or sham procedure. The number of circulating neutrophils and serum concentrations of tumor necrosis factor-alpha, nitrite, and electrolytes were also determined in each group.

RESULTS

Motor nerve conduction velocity and sensory conduction velocity in the 30-minute excision (n = 10) and sham group (n = 5) were not significantly different. Motor nerve conduction velocity and sensory conduction velocity in the nonexcised group (n = 10) and 3-hour excision group (n = 10) were significantly decreased. Serum tumor necrosis factor-alpha concentration was elevated 6 hours after burn in nonexcised animals (n = 9) and in 3-hour excision mice (n = 8) but was not significantly different in the sham (n = 8) and the 30-minute excision group (n = 7).

CONCLUSION

The authors conclude that burn wound excision at 30 minutes but not at 3 hours prevents the nerve conduction deficits measured in mice with 20 percent body surface area burns. The cellular basis of burn-induced neuropathy is unknown, but nitric oxide and tumor necrosis factor alpha-alpha appear to play a role.

Pediatric surgical site and soft tissue infections

OBJECTIVE

The purpose of this review is to provide background and a concise set of definitions for pediatric surgical site and wound infections.

DESIGN

The information discussed in this report is derived from a literature review and discussion at an international consensus conference on pediatric sepsis.

MEASUREMENTS AND MAIN RESULTS

There is a paucity of literature on pediatric surgical site and wound infection definitions. Excluding burn wounds, surgical site and wound infections rarely lead to overwhelming sepsis. Nevertheless, surgical site or wound infections including pressure ulcers can lead to significant morbidity in the pediatric critical care setting.

CONCLUSIONS

Although surgical site and wound infections rarely lead to intensive care unit admissions, definitions are still valuable for stratifying potential candidates for sepsis trials.

Sepsis in pediatric burn patients

OBJECTIVE

To review the specific infections common in pediatric burns, including their categorization, diagnosis, and treatment.

DESIGN

Review of the literature and expert opinion.

RESULTS

Children with serious burns are prone to a host of septic complications. This proclivity to infection is secondary to the immunosuppressive effect of burn injury, the loss of the skin and mucosal physical barriers, and the requirement for invasive support devices.

CONCLUSION

Sepsis is common in the pediatric burn patient and can markedly increase morbidity and mortality. Anticipation, prompt diagnosis of infection, and effective therapy can result in successful outcomes for many of these children.

Safety and efficacy of a proteolytic enzyme for enzymatic burn debridement: a preliminary report

A prospective, non-comparative study design was used to describe our experience with a bromelain-derived debriding agent, Debridase, in 130 patients with 332 deep second degree and third degree burns treated between 1984 and 1999. Debridase was applied after saturating the burns with a moist dressing for 2-24h. Debridase was applied for a period of 4h under an occlusive dressing. Mean patient age was 18.6 +/- 19.3, 42 (32.3%) were female, and 63 (48.5%) were children under age 18. Most burns were small. Debridase was applied once in 241 (72.6%) of the 332 wounds, twice in 67 (20.18%) cases, three times in 12 (3.61%) cases, and four times in 2 (0.6%) cases. The percentage debridement by number of applications was 89 +/- 21% for a single application, 77 +/- 27% for two, and 62 +/- 27% for three Debridase applications, respectively. There were no significant adverse events. The availability of a fast acting, reliable and complication-free enzymatic debriding agent may open new horizons and provide a new treatment modality for burns.

Initial experience with a composite autologous skin substitute

Patients with large burns are surviving in increasing numbers, but there remains no durable and reliable permanent skin replacement. After initial favorable small animal experiments, a pilot trial of a composite skin replacement was performed in patients with massive burns. A composite skin replacement (CSR) was developed by culturing autologous keratinocytes on acellular allogenic dermis. This material was engrafted in patients with massive burns and compared to a matched wound covered with split thickness autograft. With human studies committee approval, 12 wounds in 7 patients were grafted with CSR while a matched control wound was covered with split thickness autograft. These 7 children had an average age of 6.4+/-1.4 yr and burn size of 75.9+/-5.0% of the body surface. Nine wounds were acute burns and three were reconstructive releases. Successful vascularization at 14 days averaged 45.7+/-14.2% (range 0-100%) in the study wounds and 98+/-1% (range 90-100%) in the control sites (P<0.05). Reduced CSR take seemed to correlate with wound colonization. All children survived. While CSR did not engraft with the reliability of standard autograft, this pilot experience is encouraging in that successful wound closure with this material is possible, if not yet dependable. It is hoped that a more mature epidermal layer may facilitate engraftment, and trials to explore this possibility are in progress.

Trends in blood conservation in burn care

Traditional burn surgery is very bloody, but wide use of blood conserving strategies is becoming common. Uniform application of blood conserving techniques of burn wound excision may substantially decrease blood utilization in burn patients. We chose to examine this trend in our unit. All fresh frozen plasma (FFP) and packed red blood cell (pRBC) use in children with burns of 10% or more of the body surface who were admitted during 2-3 year intervals, separated by a decade, was reviewed in detail. Three subgroups were separately analyzed: children with 10-24% (small), 25-49% (medium) and 50-100% (large) body surface area burns. Between these two intervals a major emphasis was made in techniques of blood conservation during surgery and fresh frozen plasma was replaced by 5% albumin as the routine resuscitative colloid. In Group 1, there were 189 children, of whom 184 (97%) survived to discharge. In Group 2, there were 203 children, of whom 199 (98%) survived to discharge (N.S.). All subgroups were well matched for age, weight and burn size. Discharge hemocrits exceeded 30% in all subgroups. Reductions in FFP use were 100, 95 and 97% in the small, medium and large burn size groups, respectively. Reductions in pRBC use were 89, 63, and 80% in the small, medium and large burn size groups, respectively. These differences were all highly significant (P<0.001). Uniform application of blood conserving techniques of burn wound excision result in highly significant reductions in blood product exposure without sacrifice of clinical outcomes.

Using skin replacement products to treat burns and wounds

Much progress has been made toward the development of artificial skin replacement products. Continued research promises to bring more products to the marketplace, and each new product seems to develop a niche in the field of skin replacement. However, although each skin replacement product has unique properties and advantages, nothing works as well as a patient's own skin. Clinicians can only hope for an off-the-shelf skin replacement product that can be applied to a wound and yield a permanent, dependable dermis and epidermal skin replacement for all patients.

Enteral nutritional support and wound excision and closure do not prevent postburn hypermetabolism as measured by continuous metabolic monitoring

BACKGROUND

Estimation of nutritional needs in burn patients is difficult. In 24 severely burned patients, we measured CO2 production and O2 consumption continuously during their period of mechanical ventilation.

METHODS

Patients with extensive burns were placed on a continuous metabolic monitor (CMM) (Puritan Bennett Co., Kingwood, TX), and metabolic expenditure was recorded each 24 hours. High protein enteral feedings were started within several hours of admission, and administration rates were adjusted to meet daily caloric demands as determined by the CMM. Full-thickness wounds were excised as early as patient condition permitted, and wounds were closed with autograft, allograft, or TransCyte (Advanced Tissue Sciences Inc., La Jolla, CA). Daily 24-hour caloric needs as measured by CMM were compared with baseline caloric needs predicted by the Harris-Benedict equation and also compared with actual daily caloric intake. Patients were removed from study when they were off continuous mechanical ventilation.

RESULTS

A total of 24 patients were studied, with a mean age of 46 years and a 44% total body burn size (partial- and full-thickness). All full-thickness burns were completely excised by a mean of 6.5 days postburn. Mean daily energy expenditures remained elevated through the duration of the study period (42 days), with a mean elevation of 184.9% of baseline as predicted by Harris-Benedict equation. Patients received enteral feedings, which met 99.4% of actual caloric needs as predicted by CMM during the study period.

CONCLUSION

Continuous metabolic monitoring demonstrates that early wound excision and wound closure, coupled with aggressive enteral nutritional support with high protein formulas, do not prevent the marked hypermetabolism that accompanies thermal injury.

Solid organ procurement from burned children

BACKGROUND

Burns have constituted a traditional contraindication to solid organ procurement because of concerns that such organs may be damaged by burn shock associated splanchnic ischemia and contaminated by burn wound manipulation associated bacteremia.

METHODS

Over a 5-year period, we attempted solid organ procurement from five burned children who had suffered concurrent anoxic brain injury.

RESULTS

These four boys and one girl had an average age of 8.1 years (range, 2.5-12 years) and burn size of 29% (range, 4-70%). All were injured in house fires and four of five (80%) required prehospital external cardiac compressions. Brain death was declared an average of 35 hours (range, 2.75-77 hours) after injury. Solid organs procured and successfully transplanted from this group were 4 livers, 10 kidneys, and 2 hearts. Two of the livers and one heart were placed into pediatric recipients. Procured tissues included three sets of cardiac valves, and two corneas. All solid organs transplanted were functional at 6 months, although longer follow-up is not available.

CONCLUSION

Early identification and diagnosis of brain death during resuscitation of burn patients with anoxic brain injury, combined with careful resuscitation and support of the brain dead potential organ donor, can result in the recovery of suitable solid organs and tissues for transplantation.

Staged high-dose epinephrine clysis is safe and effective in extensive tangential burn excisions in children

Prodigious blood loss commonly accompanies extensive tangential burn excisions. Staged high-dose epinephrine clysis may facilitate blood conserving excisional burn surgery. Prospective data was collected in 25 consecutive children who underwent tangential excision over the torso of at least 10% of the body surface with staged high dose epinephrine clysis. The children had an average age of 6.3 +/- 1.1 years and burn size of 45.7 +/- 3.9%. Total operative wound size (excision plus donor site) averaged 2 +/- 0.8% of the body surface. Total dose of epinephrine averaged 24.6 +/- 2.8 mcg/kg. Based on pre- and postoperative hematocrit and known volume of transfusion, the percent of the total blood volume lost per percent total wound generated averaged 0.98 +/- 0.19% of the blood volume per % of the body surface; 18 of the children (72%) required no blood in the perioperative period. There were no complications related to epinephrine use, graft take averaged 98 +/- 0.6% and all children survived and have been discharged home in good condition. Due to its rapid metabolism, subcutaneous epinephrine at high doses can be repetitively administered as long as time is allowed for its metabolism to occur. Use of this technique facilitates a marked reduction in blood requirements for these traditionally bloody operations.

A 15-year experience with varicella infections in a pediatric burn unit

Because of their well described global immunosuppression, varicella infection may be hazardous in burned children. It is therefore important to prevent cross-infections within pediatric burn units. We describe a 15-year experience with varicella in a pediatric burn unit, focusing on the morbidity associated with the infection and measures that have been effective in the prevention of cross-infection. We found that varicella infection in acutely burned children is associated with pneumonitis, but little wound related morbidity. Despite the deceptively long incubation period, prompt identification and isolation of index cases was associated with an extremely low incidence of cross-infection. Until widespread administration of varicella vaccine confers herd immunity, varicella remains a threat to hospitalized young children, highlighting the importance of a well planned and executed index case isolation strategy.

Carbon dioxide laser ablation with immediate autografting in a full-thickness porcine burn model

OBJECTIVE

To compare the long-term clinical and histologic outcome of immediate autografting of full-thickness burn wounds ablated with a high-power continuous-wave CO2 laser to sharply débrided wounds in a porcine model.

SUMMARY BACKGROUND DATA

Continuous-wave CO2 lasers have performed poorly as tools for burn excision because the large amount of thermal damage to viable subeschar tissues precluded successful autografting. However, a new technique, in which a high-power laser is rapidly scanned over the eschar, results in eschar vaporization without significant damage to underlying viable tissues, allowing successful immediate autografting.

METHODS

Full-thickness paravertebral burn wounds measuring 36 cm2 were created on 11 farm swine. Wounds were ablated to adipose tissue 48 hours later using either a surgical blade or a 150-Watt continuous-wave CO2 laser deflected by an x-y galvanometric scanner that translated the beam over the tissue surface, removing 200 microm of tissue per scan. Both sites were immediately autografted and serially evaluated clinically and histologically for 180 days.

RESULTS

The laser-treated sites were nearly bloodless. The mean residual thermal damage was 0.18+/-0.05 mm. The mean graft take was 96+/-11% in manual sites and 93+/-8% in laser sites. On postoperative day 7, the thickness of granulation tissue at the graft-wound bed interface was greater in laser-debrided sites. By postoperative day 180, the manual and laser sites were histologically identical. Vancouver scar assessment revealed no differences in scarring at postoperative day 180.

CONCLUSIONS

Long-term scarring, based on Vancouver scar assessments and histologic evaluation, was equivalent at 6 months in laser-ablated and sharply excised sites. Should this technology become practical, the potential clinical implications include a reduction in surgical blood loss without sacrifice of immediate engraftment rates or long-term outcome.

Death in the burn unit: sterile multiple organ failure

It has been our impression over the years that the most common cause of death in our burn patients is multiple organ failure, despite the clinical absence of uncontrolled infection at the time of death. A six year review of all deaths in our unit confirmed this impression, revealing that multiorgan failure is indeed the most common cause of death (48 patients, 67 per cent), followed rather distantly by early withdrawal of support (15 patients, 21 per cent), resuscitation failure (4 patients, 6 per cent) and isolated pulmonary failure (4 patients, 6 per cent). Finally, we found that our patients dying of multiorgan failure, although often having had multiple small infections during their course, were indeed clinically uninfected at the time of death. These findings are consistent with the supposition that uncontrolled systemic inflammation, initially triggered by tissue injury and isolated infection, persists despite control of these infections and leads to multiple organ failure and death.

Physiologic hypoalbuminemia is well tolerated by severely burned children

BACKGROUND

Physiologic hypoalbuminemia, defined as a plasma albumin (pl-ALB) of 1.0 to 2.5 g/dL, is a component of the injury response. A consensus on the need for albumin supplementation in this setting is lacking.

METHODS

We examined 27 consecutive children (age, 7 +/- 6 years) with > 40% body surface burns (mean, 59 +/- 18%) during their initial 4 weeks of care. Patients were managed with an albumin-supplementation protocol that tolerated profound physiologic hypoalbuminemia. Intravenous albumin was administered by infusion of 1 to 2 g/kg/d when pl-ALB fell below 1.0 g/dL, or below 1.5 g/dL in the presence of enteral feeding intolerance or pulmonary dysfunction. Supplementation was stopped when pl-ALB reached 2.0 g/dL.

RESULTS

Mean pl-ALB was 1.7 g/dL overall. Infusion for pl-ALB < 1.0 g/dL was needed for 70% (n = 19) of the patients. Profound physiologic hypoalbuminemia was constant, that is, mean weekly pl-ALB never exceed 2.5 g/dL in any patient. Mean plasma globulin rose during the 4 week period from 2.3 +/- 0.1 at week 1 to 3.1 +/- 0.1 at week 4. Diarrhea was negligible (19 of 756 patient days), nasogastric feedings were well tolerated, PaO2/FiO2 ratios remained well above 150, wounds healed satisfactorily, and all children survived and have been discharged home.

CONCLUSIONS

Profound physiologic hypoalbuminemia (pl-ALB of 1.0-2.5 g/dL) does not have adverse effects on pulmonary or gut function, wound healing, or outcome in severely burned children, perhaps because of a compensatory increase in acute-phase proteins reflected in plasma globulin.

Inhaled nitric oxide in burn patients with respiratory failure

BACKGROUND

Inhaled nitric oxide (NO) has the potential to improve ventilation/perfusion matching and decrease pulmonary artery pressure in patients with profound respiratory failure.

METHODS

Eight patients, average age of 35 years (range, 2.5-77 years) and burn size 49% (range, 19-80%), with inhalation injury and respiratory failure failing conventional management (average Pao2/FiO2 ratio (PFR) 85) were given inhaled NO at 20 ppm.

RESULTS

An immediate mean increase in PFR of 10% and a decrease in pulmonary artery mean pressure of 7.8% was noted. At 24 hours, the average improvement in PFR was 28% and that in pulmonary artery mean pressure was 7.7%. Although not reaching statistical significance, these changes were more pronounced in those patients who went on to survive. There was no hypotension attributed to NO administration, and maximum methemoglobin levels averaged 0.9%.

CONCLUSIONS

Inhaled NO can be safely administered to selected burn patients with severe respiratory failure who are perceived to be failing conventional support. Although current data are not adequate to support its general use, an immediate and sustained improvement in PFR and pulmonary artery mean pressure may correlate with eventual recovery of pulmonary function. Continued evaluation in controlled settings seems warranted and is in progress.

Effects of E-selectin and P-selectin blockade on neutrophil sequestration in tissues and neutrophil oxidative burst in burned rats

OBJECTIVE

Neutrophil deposition in tissues (leukosequestration) after shock may produce local tissue injury from proteases and high-energy oxygen species released from sequestered neutrophils. The initial step in the binding of neutrophils to capillary endothelium is the interaction of adhesion molecule (selectin) receptors between neutrophils and endothelial cells. We quantified leukosequestration in the tissues of burned rats using two methods of analysis: a) measurement of lung myeloperoxidase; and b) measurement of radiolabeled neutrophils and erythrocytes deposited in multiple tissues. We then determined the ability of a selectin receptor blocking agent to affect neutrophil deposition in tissues after burn injury.

DESIGN

Prospective, controlled, laboratory study.

SETTING

University research laboratory.

SUBJECTS

Male Wistar rats (200 to 300 g).

INTERVENTIONS

After tracheostomy and venous cannulation, rats received 17% total body surface area full-thickness contact burns and were resuscitated with saline (20 mL i.p.). Experimental animals received 2 mg/kg body weight i.v. administration of a P- and E-selectin blocking monoclonal antibody, CY-1747, immediately after burn. Lung tissue neutrophils were estimated by measuring myeloperoxidase in lung tissue. Neutrophil retention in lung, liver, spleen, gut, skin, muscle, kidney, and brain tissues was determined by removing (preburn) and differentially radiolabeling neutrophils (111In) and erythrocytes (51Cr), reinfusing cells 4.5 hrs after burn, and measuring tissue radioactivity 30 mins later. Edema was estimated by measuring extravasated 125 I-labeled albumin in the various tissues. Peripheral blood neutrophils were analyzed for intracellular hydrogen peroxide content, utilizing a fluorescent dye that reacts with hydrogen peroxide, coupled with analysis of cell fluorescence by flow cytometry.

MEASUREMENTS AND MAIN RESULTS

Myeloperoxidase concentration was increased in lungs 5 hrs after burn (p < .05), indicating neutrophil deposition. Radioisotope studies demonstrated significant (p < .05) leukosequestration into the lung, gut, kidney, skin, and brain tissues at 5 hrs after burn. Flow cytometry showed increased intracellular hydrogen peroxide content in peripheral blood neutrophils 5 hrs after burn. Tissue edema, manifested by radiolabeled albumin retention, was not seen in any tissues. Postburn neutrophil deposition in lungs and liver was blocked (p < .05) by administration of CY-1747 after burn, but maximal neutrophil hydrogen peroxide content was unaffected.

CONCLUSION

Burn injury in rats results in accumulation of neutrophils in multiple tissues. Neutrophil deposition in the lungs and liver is blocked by administration of the E/P-selectin blocking antibody, CY-1747. Since sequestration of metabolically active neutrophils may induce tissue injury, therapies that block postburn leukosequestration may improve clinical outcomes by limiting remote tissue injury.

Permissive hypercapnia as a ventilatory strategy in burned children: effect on barotrauma, pneumonia, and mortality

OBJECTIVE

To document the incidence of barotrauma, pneumonia, and respiratory death associated with a mechanical ventilation protocol based on permissive hypercapnia in pediatric burn patients.

DESIGN

Retrospective review.

MATERIALS AND METHODS

Patients were managed using a mechanical ventilation protocol based on permissive hypercapnia, tolerating moderate (pH > 7.20) respiratory acidosis to keep inflating pressures below 40 cm H2O.

MAIN RESULTS

Over a 2.5-year interval, 54 burned children (11% of 495 acute admissions) with an average age of 6.5 years (range 5 weeks to 17 years), average burn size of 44% (range 0 to 98%), and median burn size of 46% required mechanical ventilatory support for an average of 12.5 days (range 1 to 56 days). Inhalation injury was diagnosed in 34 (63%) of the children and 72% percent were admitted within 24 hours of injury. Overt barotrauma occurred in 5.6% of the patients, pneumonia in 32%, and respiratory death in 0%.

CONCLUSIONS

A conventional ventilation protocol based on permissive hypercapnia is associated with acceptable rates of barotrauma and pneumonia. The low incidence of respiratory death associated with this strategy suggests that it also minimizes ventilator-induced lung injury.

Effects of early and delayed wound excision on pulmonary leukosequestration and neutrophil respiratory burst activity in burned mice

BACKGROUND

Tissue myeloperoxidase (MPO) is a marker of neutrophil (PMN) accumulation in tissues (leukosequestration). We measured MPO in the livers, guts, and lungs of mice after burn injury and studied the additive effect of burn excision on lung MPO. Lung histologic characteristics were also examined. PMN respiratory activity was assessed by measuring intracellular H2O2 content.

METHODS

Mice received 32% total body surface area (TBSA) burns; some underwent burn excision followed by wound closure with allograft skin, either immediately or 48 hours after burn. Tissue MPO was measured by a colormetric assay, and intracellular H2O2 was quantified by flow cytometry.

RESULTS

MPO was elevated in lungs 8 to 24 hours after burn (p < 0.05) but not in the liver or ileum. Other burned mice received either immediate or 48-hour-delayed wound excision and allografting. In controls a similar-size area was excised and grafted with normal or burned skin. Burned animals had increased lung MPO compared with nonburned animals (p < 0.05). Highest lung MPO levels were seen after burn/immediate excision (p < 0.001). Lung MPO levels were not different comparing unburned mice undergoing skin excision and grafting with either nonburned or burned skin. When burn excision was delayed 48 hours, lung MPO was increased moderately (p < 0.05) but remained far below levels in mice that were excised immediately after burn. PMN influx into lung tissues was confirmed by histologic examination. PMN H2O2 production was increased in burned mice and was additionally increased after immediate wound excision.

CONCLUSIONS

Although burn injury produces pulmonary leukosequestration, the phenomenon is unrelated to local effects of burned skin. In this experimental model immediate postburn wound excision increased pulmonary leukosequestration to higher levels than after burn injury alone, and intracellular H2O2 content also increased. Pulmonary leukosequestration may predispose to lung injury, possibly limiting the benefits of wound excision performed extremely early postburn.

Solid organ procurement from burn patients

With the increasing success or organ transplantation and the consequent increasing scarcity of suitable organs, many traditional contraindications to organ procurement are being reconsidered. One such traditional contraindication to organ procurement is burn injury. We report a case of successful multiorgan procurement from a child with an extensive burn and propose guidelines for solid organ harvest from burn patients.