Current And Emerging Modalities In Wound Debridement
Larval therapy. Maggot therapy (biosurgery) is a form of biological debridement known since antiquity. The larvae of Lucilia sericata (green bottle fly) secrete enzymes that break down necrotic tissue into a liquid. The larvae then ingest this liquid. The maggot secretions also contain antibacterial substances. They also promote wound healing and amplify human fibroblast and chondrocyte growth. The method is rapid and selective although patients are usually reluctant to submit to the procedure.
Typically, one would place larvae in the wound bed twice a week and leave them in place for 24 to 72 hours with a recommended dose of 10 to 15 larvae per cm2. One can also utilize maggot therapy with a biobag, which contains the larvae and prevents escape.
Ultrasound debridement. Depending on frequency and intensity, ultrasound can exert a range of effects on ulcers. This versatility allows one to use ultrasound on nearly every type of wound. The benefits of ultrasound are evident in the cavitation effect and the direct stimulation of cells.
In cavitation, bursting microbubbles assist in the fibrinolytic separation of denatured protein, which results in selective debridement and fragmentation of non-viable tissue. Cavitation also can have a direct bactericidal effect.
The stimulation of cells (via fluid shear stress) causes the release of nitrous oxide. This subsequently results in resolution of the vasospasm, thereby increasing blood flow around the wound. Additionally, fibroblasts, macrophages and endothelial cells are stimulated.10
Examples of ultrasound debridement products include Qoustic Wound Therapy System (Arobella Medical) and SonicOne (Misonix). The Qoustic Wound Therapy System delivers focused ultrasonic energy as it lightly contacts the wound bed, gently separating and removing unwanted tissue while preserving healthy granulation tissue.
Hydrosurgery. Jet lavage debridement is the evolution of wound irrigation. Clinicians can use the irrigation from hydrosurgery to physically remove debris, loose tissue, etc., from the wound. There are a number of hydrosurgery products. Some are gentle while others are almost like a surgical water knife. The versatility of hydrosurgery intensities enables clinicians to use these devices on almost all types of wounds.
Examples of these devices include MIST Therapy (Celleration) and the Versajet (Smith and Nephew). MIST Therapy is a painless, low frequency, low intensity, non-thermal, non-contact ultrasound-generated mist. Promoting healing by mechanical cell stimulation, MIST Therapy allows clinicians to perform gentle wound debridement that reportedly reduces the wound’s bacterial bioburden and increases angiogenesis.11
Another potential benefit is the possible use of antibiotic/antiseptic solutions (super-oxidized solutions and polyhexanide solutions) instead of saline. When one uses a hydrosurgical device in conjunction with antiseptic irrigation, it may act as a physical and biological debrider.
Super-oxidized solution is a hypotonic solution that contains hypochlorous acid, sodium hypochlorite, chlorine dioxide, ozone, hydrogen peroxide and sodium chloride. Super-oxidized solution is an electrochemically processed aqueous solution manufactured from pure water and sodium chloride. Reactive species of oxygen and chlorine (which have formed via electrolysis) create an unbalanced osmolarity. This disparity in osmolarity subsequently causes damage to the integrity of the cell membrane and then reacts and denatures the lipids and proteins of single cell organisms. This is a direct result of the osmolarity difference between the ion concentrations of the solution and single cell organism.
Multicellular organisms are not prone to such osmolarity changes, which is why these solutions are safe to use on the wound. An example of a super-oxidized solution would be Microcyn (Oculus Innovative Services).