J.K. Prasad

Superoxide dismutase prevents lipid peroxidation in burned patients

Animal models and human studies have shown that conjugated dienes rise in the plasma after thermal injury. These dienes may serve as a marker of oxygen radical-mediated tissue injury. Twelve burn patients were randomized to receive the antioxidant enzyme polyethylene glycol-conjugated superoxide dismutase (PEG-SOD). Patients received either 500 or 1000 units per kilogram of PEG-SOD intravenously within 6 h of injury. Plasma samples were collected and conjugated diene levels were compared to diene levels of burn patients not treated and to diene levels from normal volunteers. Conjugated diene levels were increased in burn patients. PEG-SOD in either dose initially decreased conjugated diene levels in the plasma of both treatment groups. By 72 h, the diene levels increased in the 500 unit/kg group, but remained at near control levels in the 1000 unit/kg group for up to 200 h after injury. These data suggest that PEG-SOD is capable of preventing conjugated dienes formed as the result of oxygen radical production. It appears that 1000 units/kg is more effective than 500 units/kg in preventing conjugated diene formation.

Use of amnion for the treatment of Stevens-Johnson syndrome

Stevens-Johnson syndrome (toxic epidermal necrolysis) has similar pathophysiologic characteristics to extensive partial-thickness burns. Successful treatment of a 6-year-old with this syndrome denuding 95% of her body surface, with 6.5 square feet of amnion is reported.

A review of the reconstructive surgery needs of 3167 survivors of burn injury

A retrospective review of all patients admitted for acute care over the past 15 years was undertaken to identify readmission for reconstructive surgery. Of 3167 survivors 629 or 19.9 per cent were readmitted for at least one reconstructive procedure. Those patients requiring readmission for reconstructive surgery were younger and had larger total body surface burns compared to the group that were not readmitted for reconstructive surgery. The percentage of patients now being readmitted for reconstructive surgery is decreasing significantly and covers all size burns. The most common area of reconstruction, by frequency, involved the hand and wrist, arm and forearm, face, and neck. These data indicate that the goal of reducing the incidence of burn scar contractures in this patient population is being achieved. However, further work needs to be done to reduce the frequency of reconstructive surgery and to identify those variables which predispose patients to burn scar contractures which are amenable to intervention.

A Prospective Controlled Trial of Biobrane Versus Scarlet Red on Skin Graft Donor Areas

A prospective trial of Biobrane versus scarlet red as a skin graft donor site dressing was done in 21 burn patients with mean total body surface area burns of 31.9%. Corresponding body areas were randomly selected on each patient to receive one of the dressings. Daily evaluations were made of subjective expression of pain, exudate formation and infection, and time of separation of the dressing from the wound. Biobrane was found to be superior in reducing donor site pain. However, with Biobrane there was a higher incidence of infection (57% v 9.5%) and a significant delay in separation from the wound. Scarlet red was found to be more cost-effective. Occlusive dressings have previously been shown to have a high incidence of complications (30%). In extensive burns, isolating the donor site from the wound is difficult and may lead to increased complications. Scarlet red appears to be superior to Biobrane for skin graft donor sites in this patient population.

Metabolic alterations in burn patients: detection of adenosine triphosphate degradation products and lipid peroxides.

Seven patients admitted to the University of Michigan Burn Center with greater than 20 per cent total body surface area burns were studied for evidence of oxygen radical production, as demonstrated by serum lipid peroxides, and adenosine triphosphate (ATP) degradation, based upon ATP degradation products in blood (serum purines) and urine (urine purines and urine uric acid). Lipid peroxides (conjugated dienes) were elevated beginning on day 1 postburn and remained elevated up to day 5, the duration of the study. ATP degradation products were elevated during the initial 24 h postburn but rapidly fell to normal levels. This study provides evidence of biochemical alterations in thermally injured patients similar to observations in animal models which demonstrate that ATP degradation and the production of oxygen radicals are part of the initial response to thermal trauma.

A survey of wound monitoring and topical antimicrobial therapy practices in the treatment of burn injury.

A survey was done to determine how burn wound microbial monitoring is performed and how topical antimicrobial agents are employed. The survey was sent to 90 burn-care facilities, which comprised most of the major burn centers in the United States. The survey contained questions concerning frequency and techniques of wound monitoring, personnel involved in monitoring, as well as questions about how decisions were made to initiate topical antimicrobial therapy, which agents were selected, and how they were administered. Sixty of 90 facilities (66%) responded to the survey. Although there were few areas of unanimous agreement, several trends did emerge. Most facilities monitored burn wounds for microbes (92%). Wound monitoring was typically done at least twice weekly by either surface swab or quantitative biopsy. Nursing staff played a significant role in specimen collection in 69% of facilities and were solely responsible for obtaining biopsy specimens in 29% of facilities that used biopsies exclusively. All responding facilities used topical antimicrobial agents; silver sulfadiazine was the most popular (95%). Only 33% of facilities surveyed had their own laboratory for microbial monitoring. Rapid techniques for early diagnosis of wound sepsis were used in 20% of units, and topical antimicrobial testing was used in 17% of facilities surveyed.

Rapid quantification of bacterial and fungal growth in burn wounds: biopsy homogenate Gram stain versus microbial culture results

A prospective analysis of 370 burn wound biopsies was done to correlate Gram-stain results from biopsy homogenates with quantitative culture results. The number of bacteria seen in a total of 10 oil immersion microscope fields of Gram-stained homogenates was correlated with significant microbial growth (1 x 10(5) organisms/gram of tissue) of the same biopsy homogenate plated on trypticase soy agar. Of the biopsies examined, Gram-negative rods were present in 36.8 per cent, Gram-positive cocci in 49.7 per cent and yeast in 15.9 per cent. Mixtures of organisms were present in 24.3 per cent. When Gram stains showed one or more organisms per oil immersion microscope field, the correlation with significant microbial growth was 94.5 per cent or more. When five or more organisms were seen per field, the correlation with significant growth became 97 per cent or greater. When no organism was seen on Gram stain, the cultures grew significant numbers of organisms 19.1 per cent of the time or less. This false-negative rate was considered to be high. It is believed, however, that this method of early detection of significant burn wound microbial growth may prove to be valuable in the management of severely burned patients.

The elderly, disabled and handicapped adult burned through abuse and neglect

A retrospective review of 1152 acute burns treated at the University of Michigan Burn Center during the past 5.5 years identified 26 adult patients in whom abuse and neglect was suspected. These patients, 12 females and 14 males, had an average age of 42 years and average total body area burn (TBA) of 18 per cent. Eight of these cases were in situations in which the question of inflicted injury was raised and 18 were in situations of neglect and/or improper supervision. Seven (27 per cent) died from their injury. All of these adults were either very old, mentally impaired, and/or physically handicapped. Twenty-three were burned in health care facilities or institutions. Adult abuse in the elderly, handicapped and disabled population is similar to that found in child abuse and includes characteristic burn patterns, a story that does not fit the injury, and a delay in seeking medical care. An increased awareness of the problem is necessary for improved diagnosis and management of these patients.

Gastrointestinal haemorrhage in burn patients.

Gastrointestinal haemorrhage after burn injury remains a potentially lethal problem. A retrospective review of 3852 burn patients over 15 years revealed an incidence of gastrointestinal haemorrhage of 2.2 per cent and a mortality of 0.16 per cent. This low incidence of haemorrhage and mortality can be directly related to an aggressive prophylactic treatment with antacid and titration of the gastric pH to 5.5 or above. With this aggressive management programme, few operative procedures were required. A review of autopsy data showed that the site of haemorrhage was distributed throughout the gastrointestinal tract with the predominant site being the stomach.

Susceptibility of pseudomonas and staphylococcus wound isolates to topical antimicrobial agents: a 10-year review and clinical evaluation

A 10-year review of Ps. aeruginosa and Staph. aureus susceptibility to various topical agents is presented. Susceptibility testing was performed using the agar well diffusion (AWD) method. A reduction in microbial growth to numbers less than 10(5) per gram of tissue in the wound, measured by quantitative biopsy, was compared with predicted susceptibility test results. In this measurement of clinical efficacy, silver sulphadiazine and mafenide acetate compared most favourably with AWD results, 83 per cent and 82 per cent respectively. However, nitrofurazone only reduced bacterial counts to less than 10(5) per gram 42 per cent of the time when an inhibition zone was present. Hydrogen peroxide solution (1 per cent) was 100 per cent effective by the AWD test, but no relationship to clinical efficacy could be shown. Minimal inhibitory concentration (MIC) data for gentamicin sulphate was compared to AWD and showed a positive relationship of greater than 80 per cent for both organisms. The AWD test has been a useful aid in the decision-making process for the choice of topical agent by providing data which eliminates agents inappropriate for use.