Laboratory Research
Though advanced absorbent dressings may be able to adhere to slough and elements of necrotic tissue, they are based on fibers not particularly designed, in their chemical structure to adhere to wound debris. We describe here the ability of a fiber, deliberately imbued with a high degree of negative charge, to adhere to slough like material likely to be present in many wounds.
Methods:
Alginates, a carboxymethylcellulose based dressing, and an engineered polyacrylae fabric dressing made from highly negative fibers, were applied to fibrin reconstituted in vitro (based on fibrinogen and human thrombin). A weight was applied over the dressing in order to simulate a dressing subjected to compression at a level of 40 mmHg. The final adhesion was evaluated after 24-hr incubation at room temperature.
Results:
With five samples of each dressing done to confirm repeatablity, the highly charged absorbent fiber based on polyacrylate technology was able to completely remove via an adhesion process from the test surface area, all of the slough like fibrin gel. The other two dressing materials removed very little of the gel via an adhesion process under the same conditions.
Discussion:
The results of the experiment prove the contention that highly (negatively) charged dressings have the ability to submit physical forces to the underlying slough or debris like material to allow easy removal of slough via non sharp methods from a wound surface. The slough like material compared in this study is the positively charged material, fibrin gel. This effect of the supercharged dressing helping support the debridement of slough has been seen in comparative clinical studies, however, the laboratory technique here further confirms the relative abilities of the new supercharged biomaterial to remove slough under controlled conditions compared to other traditional dressing methods. It is essential that to acheive this effect, that the dry dressing material tested here be applied directly to the moist wound-slough surface. Prewetting of this new advanced dressing is therefore not recommended.