Topical Antibiotic Ointment Versus Silver-containing Foam Dressing for Second-degree Burns in Swine

Abstract

Objectives: Second-degree burns are very common but their management is controversial. These burns may be treated with either topical antimicrobial agents or advanced occlusive dressings; however, there is no established treatment comparator for preclinical studies. This study was designed to determine which of two commonly used comparator therapies (a silver-containing advanced dressing or a topical antibiotic ointment) resulted in faster reepithelialization and less scarring. The hypothesis was that second-degree burns treated with a topical antimicrobial ointment would heal faster and with less scarring than those treated with a silver-containing occlusive foam dressing in a porcine model. Methods:Deep partial-thickness burns were created on the flanks of three anesthetized female domestic pigs (20 to 25 kg) using a 150-g aluminum bar preheated in 80°C water bath and applied to the skin for 20 seconds using a force of 2 kg. The burn eschars were excised 48 hours later with an electric dermatome set at a depth of 0.75 mm. The wound beds were treated with a thin layer of triple-antibiotic petrolatum-based ointment (changed three times weekly) or a silver-containing foam dressing (changed once weekly). Full-thickness punch biopsies were obtained at 9, 11, 14, 16, 18, and 21 days for determination of percentage complete wound reepithelialization and at 28 days for measurement of scar depth.Results: At all dressing changes the wounds treated with the topical antibiotic appeared moist, while those treated with the silver-based dressings appeared dry. At day 21 all wounds treated with the ointment were completely reepithelialized, while only 55% of those treated with the silver dressing were reepithelialized (p < 0.001). Scar depth at day 28 was also significantly less in wounds treated with the topical antibiotic ointment (4.3 mm vs. 5.1 mm, difference = 0.7 mm; 95% confidence interval [CI] = 0.1 to 1.4 mm). There was less scar contraction in wounds treated with the topical antibiotic compared with the silver-based dressing (mean AE SD = 25.0% AE 14.6% vs. 38.9% AE 16.9%, difference = 13.9%; 95% CI = 5.7% to 22.0%).Conclusions: In this model of excised deep partial-thickness burns, a triple-antibiotic ointment enhanced reepithelialization and reduced scar depth and contraction compared with a silver-based foam dressing. This triple-antibiotic ointment should be considered as a control for studies evaluating novel topical burn therapies.ACADEMIC EMERGENCY MEDICINE 2015;22:927-933 © 2015 by the Society for Academic Emergency Medicine S econd-degree (partial-thickness) burns are very common, but their management is controversial. These burns are usually treated with either a topical antimicrobial cream or ointment or one of many advanced, silver-containing occlusive dressings. Over the past decade a large number of advanced burn dressings have been introduced into the marketplace. Many of these dressings contain silver due to its antimi-

Silver in Wound Care—Friend or Foe?: A Comprehensive Review

“…In an animal study of clean burns, Mepilex Ag had slower healing than triple antibiotic ointment. 44 For skin graft donor sites, Acticoat has been found to delay epithelialization by more than 50% when compared to occlusive dressings. 45 As mentioned above, dressings containing nanocrystalline silver lead to silver ion concentrations in the wound of up to 70 ppm, which is above the toxic threshold for keratinocytes and fibroblasts.…”

Sprayable and biodegradable, intrinsically adhesive wound dressing with antimicrobial properties

“…All wounds healed at similar rates and with similar cosmetic results in terms of scarring (Figure 6a-c). While the Tegaderm dressing was found to have more complete epidermal surface coverage on wound biopsies on PWD 7 (Figure 7a), the slower rate of reepithelialization with the PLGA/PEG/Ag dressings is not surprising given the known inhibitory effects of silver on keratinocyte, fibroblasts, and epidermal cells 52,53 and did not have a negative effect on outcomes. Future studies could probe the antimicrobial efficacy of PLGA/PEG/Ag in vivo with an infection challenge model or by quantifying the bacterial burden in wounds over time.…”

Rational Selection and Use of Antimicrobials in Patients with Burn Injuries

“…46,[52][53][54] Silverbased dressings offer the antimicrobial benefits of topicals with less frequent dressing changes and better patient tolerability. [55][56][57] First introduced as a 10% ointment, mafenide is a topical sulfonamide with broad gram-positive and gram-negative activity, particularly Pseudomonas spp. 58 Mafenide offers the added benefit of eschar penetration for deep burns.…”