Topical oxygen emulsion: a novel wound therapy.

OBJECTIVE: To investigate the use of a topical oxygen emulsion (TOE), consisting of a supersaturated oxygen suspension using perfluorocarbon components, on second-degree burns and partial-thickness wounds. DESIGN: Oxygen is a required substance for various aspects of wound repair, and increased oxygen tension in a wound has been shown to stimulate phagocytosis and to reduce the incidence of wound infection. Second-degree burns and partial-thickness wounds were created on the backs of specific pathogen-free pigs. Wounds were then randomly assigned to 1 of the following treatment groups: TOE, TOE vehicle, or air-exposed control. MAIN OUTCOME MEASURE: Wounds were assessed for complete epithelialization using a salt-split technique. RESULTS: The TOE was able to significantly (P = .001) enhance the rate of epithelialization compared with both vehicle and untreated control. These data suggest that topical oxygen may be beneficial for acute and burn wounds. CONCLUSIONS: The results obtained from this double-blind, control, in vivo study demonstrate that TOE can significantly enhance the rate of epithelialization of partial-thickness excisional wounds and second-degree burns. These findings could have considerable clinical implications for patients with surgical and burn wounds by providing functional skin at an earlier date to act as a barrier against environmental factors, such as bacteria invasion. Other types of wounds may also benefit from this therapy (eg, chronic wounds and surgical incisions). Additional studies, including clinical studies, are warranted.

Over-the-counter topical antimicrobials: effective treatments?

There are many over-the-counter (OTC) bandage products available. In addition to their direct purchase by the public, many physicians provide OTC bandages to their patents after minor surgeries. The aim of this study was to evaluate in a well established porcine model the efficacy against Staphylococcus aureus of four OTC antimicrobial containing bandages as compared to two OTC ointments. Multiple partial thickness wounds were made on the backs of four pigs. The wounds were treated within 20 min after S. aureus inoculation. The wounds were cultured quantitatively at 24 and 48 h. Only one of the antibiotic bandages and one of the topical ointments were effective in reducing S. aureus proliferation in partial thickness wounds. The two treatments that were effective were the only treatments that contained neomycin. Although many OTC bandages and ointments contain antimicrobials, they may not be effective at reducing bacteria in wounds.

A wound-isolated Pseudomonas aeruginosa grows a biofilm in vitro within 10 hours and is visualized by light microscopy.

BACKGROUND: In chronic wounds, biofilms probably play a vital role in protecting bacteria from host defenses and antimicrobial medications by creating a barrier of exopolysaccharide that is difficult for the immune system and antibiotics to penetrate. A biofilm consists of an exopolysaccharide matrix that is produced and secreted by certain species of bacteria. OBJECTIVE: The purpose of this study was to visualize and time the progressing growth of a biofilm by a wound-isolated Pseudomonas aeruginosa. METHODS: P. aeruginosa that was initially isolated from a human burn wound was allowed to grow a biofilm in vitro. We used a modified Congo red staining technique to demonstrate the sequential development of a mature biofilm as examined by light microscopy. RESULTS: We show that the exopolysaccharide of the developing biofilm is visible in just 5 hours after inoculation and has the characteristics of a mature biofilm by 10 hours. CONCLUSION: The rapidity of biofilm growth suggests that bacteria in wounds possess the capacity of producing this shield against antibiotics and immune effector cells early in the infection process. Therefore, efforts to prevent or slow the proliferation of bacteria and biofilms should occur soon after a wound is created. Additionally, this staining technique can be used to demonstrate the ability of agents to slow biofilm growth or to interrupt formed biofilm and may be useful in future studies of chronically infected wounds.

Barrier and antibacterial properties of 2-octyl cyanoacrylate-derived wound treatment films.

BACKGROUND: Besides enhancing healing, an ideal dressing should prevent invasion of pathogens and control the number of bacteria already present in the wounds. OBJECTIVE: To evaluate the barrier and antimicrobial properties of a cyanoacrylate-based bandage (LAB) against Staphylococcus aureus or Pseudomonas aeruginosa on partial thickness wounds in swine. METHODS: Barrier study: Bacteria were inoculated over test materials (LAB, standard bandage, air-exposed) that were placed over wounds. The bacteria from wounds were quantitated at 24, 48, and 72 hours postinoculation. Antimicrobial study: Wounds inoculated with bacteria were covered with LAB, standard bandage, or hydrocolloid bandage or left air-exposed. The bacteria recovered from wounds were quantitated at 24 and 72 hours after treatment. RESULTS: Barrier study: No bacteria were recovered from LAB-treated wounds. Antimicrobial study: LAB reduced the number of inoculated bacteria in comparison to all other groups. CONCLUSION: LAB is effective in protecting wounds from external bacterial invasion and reducing bacterial contamination.