Early Wound Excision Research Articles

Current Management of Burns

Major burns are relatively frequent injuries that carry a high risk for morbidity and mortality. Patients at the extremes of age or with concomitant inhalation injury are at increased risk for complications and death from their thermal injuries. The initial management of thermal injuries continues to prioritize maintenance of the airway, breathing, and circulation with prompt consideration for transfer to a specialized burn care center. Early fluid resuscitation is best accomplished with an isotonic crystalloid solution to maintain tissue perfusion, hemodynamic stability and prevent remote organ failure. The necessary fluid volume is estimated from the patient's weight and percentage of body surface area burned and adjusted as determined by the patient's clinical response. Patients who have sustained an inhalation injury are at increased risk for pneumonia and require additional fluid resuscitation, meticulous pulmonary toilet and, occasionally, mechanical ventilation. Wound care following fluid resuscitation is based on topical antimicrobial therapy followed by early surgical excision and grafting to achieve wound closure and control infection. Adequate enterai nutrition is required to minimize the loss of lean body mass. Progressive improvements in the understanding of burn shock, early wound excision and closure, the control of infection, nutritional requirements and the treatment of inhalation injuries have significantly improved the survival of burn patients in recent years.

Early but not late burn wound excision partially restores viral-specific T lymphocyte cytotoxicity.

Early burn wound excision restores immunocompetence and improves patient survival, but the exact mechanisms have not yet been defined. Burn injury impairs cytotoxic T lymphocyte (CTL) activity as a function of burn size, increasing the risk of infection. The purpose of this study was to determine if early wound excision improved viral-specific CTL function. Anesthetized C57BL/6 mice (n = 20) received 0%, 20%, or 40% total body surface area full-thickness contact burns and were inoculated 3 days later with intraperitoneal lymphocytic choriomeningitis virus. Eight days after infection, or 11 days after burn, CTL effectors (E) were harvested and tested against infected, radiolabeled L-Dh targets (T) in a 51Cr-release assay, at varied E:T ratios. Dilution curves of CTL activity were compared by analysis of variance. In the second experiment, mice (n = 18) underwent a 30% burn that was totally excised and grafted on postburn days (PBDs) 0, 3, and 7. Control groups included sham burn and no excision of a 30% burn. In the third experiment, mice (n = 22) received a 30% burn that was partially, completely, or not excised on PBD 3. Control groups included sham burn with and without excision. All groups were infected with intraperitoneal lymphocytic choriomeningitis virus on PBD 3. Viral-specific CTL activity was determined on PBD 11. Both 20% and 40% burn injury impaired viral-specific CTL function. Wound excision on PBDs 0 and 3, but not on PBD 7, partially restored CTL function. Total excision of the 30% burn improved CTL activity to a greater extent than did partial excision. Burn injury inhibits viral-specific CTL activity. Early, complete wound excision augments CTL function. Improved CTL activity after burn may reduce the risk of infection, providing an immunologic rationale for expeditious wound excision.

Immediate Burn Wound Excision Restores Antibody Synthesis to Bacterial Antigen

Although burn wound excision and grafting have been shown to improve patient survival, the effects on immune function, especially humoral immunity, are not completely understood. The purpose of this study was to investigate the effect of immediate and early wound excision on antibody synthesis and B-cell proliferation, specifically, antibody response to PGPS, a ubiquitous bacterial cell wall antigen. Thirty-six male BALB/c mice were divided into four groups. Sham mice received no burn, and remaining mice received a 30% body surface area full-thickness burn. Under general anesthesia, excision and grafting was performed either 6 or 72 hr after injury (BE&G6 and BE&G72 groups). A fourth control group received burn but did not undergo excision and grafting (Burn group). Splenocytes were isolated 8 days postburn and stimulated with 2.5 μg/ml lipopolysaccharide. Anti-PGPS IgM, total IgM, and total IgG levels were determined by ELISA. B-cell proliferation, measured by [3H]thymidine uptake, was expressed as stimulation index. All B-cell functions were significantly suppressed by burn injury. Immediate excision and grafting (BE&G6) restored anti-PGPS IgM synthesis to normal, while nonspecific B-cell functions did not change significantly. Early excision and grafting (BE&G72), however, failed to significantly improve any B-cell functions. Immediate but not early BE&G restored antibody synthesis to the bacterial cell wall antigen (PGPS). Immediate BE&G may therefore lead to a decrease in bacterial infection after burn injury.

Sequential excision and grafting of the burn injuries of 1507 patients treated between 1967 and 1986: end results and the determinants of death.

The development of a more aggressive approach to burn wound management, leading to complete excision within 72 hours after burn, has led some to conclude that total early excision is a major force behind improved survival rates. We have summarized the results of treatment of 1507 patients with burn injuries treated between 1967 and 1986. Wounds were managed with use of standard topical therapy, occlusive dressings, and staged excision and grafting of full-thickness injury or deep dermal injury (not healed by 21 days). Data were analyzed with use of a logistic-regression model because, with the exception of older patient cohorts, the data did not fit the probit model. The major determinants predicting death were the percentage of body surface area burned, age, smoke inhalation, and the percentage of full-thickness burn. Concordance was 97%. These data show that aggressive sequential wound excision and grafting produces end results comparable with those achieved with complete early burn wound excision for similar age ranges and injury. Early harvest of available donor sites in patients with large burns may be more important to survival than complete early wound excision.

Management of the Mangled Hand and Forearm.

In this article the authors describe the methods and procedures that have been used to help patients regain hand and forearm function after mangling injuries. Assessment of the pathophysiologic condition, careful inventory of the injured structures, and early aggressive wound excision and reconstruction, followed by expert rehabilitation, are advocated. The importance of vascular restoration, stable skeletal fixation, and provision of adequate skin cover are stressed. In addition to describing their treatment approach, the authors emphasize the need for the surgeon to be well acquainted with each phase of the treatment process.

Artificial skin for wound healing

The care of burn patients is a difficult task. Although burn care over the last two decades has shown major advancements, the ability to treat consistently those patients with significant tissue damage and loss remains a challenge. A crucial step contributing to decreased morbidity and mortality of burn patients has been the practice of early wound excision.1–4 Removal of nonviable tissue rids the patient of local toxic mediators and the potential for colonization with subsequent local and systemic sepsis. Topical antimicrobials decrease the rate of colonization of a wound, but do not prevent microbial invasion and proliferation. Therefore, it is essential to close these wounds.

Evaluation of protocol change in burn-care management using the Cox proportional hazards model with time-dependent covariates.

Survival analysis methods are valuable for detecting intervention effects because detailed information from patient records and sensitive outcome measures are used. The burn unit at a large university hospital replaced routine bathing with total body bathing using chlorhexidine gluconate for antimicrobial effect. A Cox proportional hazards model was used to analyse time from admission until either infection with Staphylococcus aureus or discharge for 155 patients, controlling for burn severity and two time-dependent covariates: days until first wound excision and days until first administration of prophylactic antibiotics. The risk of infection was 55 per cent higher in the historical control group, although not statistically significant. There was also some indication that early wound excision may be important as an infection-control measure for burn patients.

Endotoxemia After Burn Injury: Effect of Early Excision on Circulating Endotoxin Levels

Serial circulating endotoxin measurements (quantitative chromogenic limulus assay) were performed in sera from 19 burned patients to determine the profile of circulating serial circulating endotoxin after burn and the effect of early wound excision on serial circulating endotoxin level. Results indicate an early endotoxemia with the peak serial circulating endotoxin levels 7 to 12 hours and 4 days after burn. More importantly, the level of circulating serial circulating endotoxin can be diminished by early excision; late wound excision was associated with a transient increase of serial circulating endotoxin level. Early excision, therefore, may play a critical role in limiting endotoxemia after burn injury.

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.