Debridement of Sulfur Mustard Skin Burns: A Comparison of Three Methods.

Sulfur mustard burns are characterized by delayed symptoms, slow healing, and recurrence after closure. Incomplete debridement at the level of the basement membrane is the postulated cause. Graham pioneered laser debridement of mustard burns. For field or mass-casualty use, saline wet-to-wet or antibiotic-soak debridement is more practical. In this study, we compared laser, saline, and antibiotic debridement in a porcine model of deep partial-thickness injury. Deep-dermal sulfur mustard burns were produced in 18 anesthetized Gottingen minipigs using 10-µl saturated vapor cap exposure time of 90 minutes. Debridement was started 48 hours postinjury and consisted of a single laser treatment; 5 days of 5% aqueous mafenide acetate wet-to-wet dressings; or 7 to 12 days of saline wet-to-wet dressings. Wounds were treated with daily silver sulfadiazine for 30 days and, then, assessed by histopathology, silver-ion analysis, colorimetry, and evaporimetry. All wounds healed well with no sign of infection. Antibiotic debridement showed no advantage over saline debridement. There were no significant differences between groups for colorimetry or evaporimetry. Histopathology was graded on a mustard-specific scale of 1 to 15 where higher values indicate better healing. Mean histology scores were 13.6 for laser, 13.9 for mafenide, and 14.3 for saline. Saline debridement statistically outperformed laser (P < .05) but required the longest debridement time. Laser debridement had the benefit of requiring a single treatment rather than daily dressing changes, significantly decreasing need for wound care and personnel resources. Development of a ruggedized laser for field use is a countermeasures priority.

Safety evaluation of silver-ion dressings in a porcine model of deep dermal wounds: A GLP study.

INTRODUCTION: Silver ion has strong antimicrobial properties and is used in a number of wound dressings. In burn models, silver-nylon dressings produce elevated silver levels in the wound along with minimal systemic effect. We evaluated systemic toxicity in a non-burn wound model to see if a similar pattern of silver ion distribution would occur. METHODS: Eight deep partial-thickness wounds each were created on the dorsum of 40 Gottingen minipigs using a Er-YAG Laser. Half were treated with a 21-day course of silver-nylon dressings (Silverlon®) and half were treated with moist gauze dressings. Wound, blood, liver and kidney silver levels, along with blood chemistry and hematology data were obtained at appropriate intervals. RESULTS: All wounds healed well with healing enhanced by silver-nylon dressings. Silver ion was demonstrable in all wounds treated with silver-nylon at day 21 and after 14 days of no further treatment. Silver ion was not detected in blood, liver or kidney of any animal treated with silver-nylon or control dressings. Liver and kidney function remained normal in all animals. CONCLUSION: A 21-day application of silver-nylon dressings to a non-burn dermal wound produces no systemic or local toxicity in Gottingen minipigs.

The antimicrobial spectrum of Xeroform®.

INTRODUCTION/BACKGROUND: Xeroform® is a petrolatum-based fine mesh gauze containing 3% bismuth tribromophenate. Bismuth, similar to other metals, has antimicrobial properties. Xeroform® has been used for decades in burn and plastic surgery as a donor site dressing and as a covering for wounds or partial thickness burns. Despite this, the antimicrobial spectrum of Xeroform® remains largely unknown. We examined the in-vitro efficacy of Xeroform® against common burn pathogens using zone-of-inhibition methodology in a commercial research facility. METHODS/DESIGN: Pure strains of 15 common burn pathogens including Methicillin-resistant Staphylococcus aureus (MRSA), Methicillin-sensitive Staphylococcus aureus (MSSA), Staphylococcus epidermidis, Pseudomonas aeruginosa, Enterobacter cloacae, Escherichia coli, Candida albicans, Vancomycin resistant Enterococcus, Acinetobacter baumennii, Klebsiella pneumonia, Extended spectrum beta-lactamase producing Klebsiella, Beta hemolytic Streptococcus pyogenes, Proteus mirabilis, Serratia marcescens, and Salmonella enterica ssp. Enterica were inoculated at a strength of 106-1010 CFU/ml onto appropriate agar plates. A sterile 1 in2 Xeroform® square was placed in the center of each plate, and the Zone of Inhibition (ZOI) was measured following 18-24h of incubation at 37°C. A second bismuth pharmaceutical (bismuth subsalicylate, Pepto-Bismol®) was then tested using the same methodology against the same strains of MRSA, MSSA, E. coli, K. pneumonia and S. marcescens. Finally, 3% w/v bismuth tribromophenate in glycerol suspension was tested against 13 burn pathogens for antimicrobial activity independent of the Xeroform® dressing by measure of Zone of Inhibition. RESULTS/FINDINGS: For Xeroform®, none of the fifteen pathogens had a measurable zone of inhibition on any plate. Bismuth subsalicylate showed a zone of inhibition for MSSA in 3 plates (mean of 47.2mm), in one of three plates for MRSA (13.8mm), and in one of three plates for S. marcesens (89.6mm). There was no zone of inhibition seen for K. pneumonia or E. coli. Bismuth tribromophenate, when not bound to Xeroform® showed activity against 12 of 13 pathogens. CONCLUSIONS/IMPLICATIONS: While bismuth subsalicylate, and bismuth tribromophenate unbound to Xeroform® demonstrate antimicrobial activity, it appears that Xeroform® dressings do not. The utility of Xeroform® in burn medicine may relate more to use as an impervious dressing than to antimicrobial effect. Donor sites are clean surgical wounds and clean partial thickness burns may have minimal colonization present. In such circumstances, an inactive and impervious dressing may be all that is necessary to promote wound healing.