Kucisec-Tepes Nastja
Acta Med Croatica. 2016 Mar;70(1):33-42.
Chronic wound does not heal within the expected time frame because it remains in the inflammation phase of healing. The reason for this is the presence of necrotic tissue and a large number of microorganisms, primarily bacteria that secrete the biofilm, along with ischemia, hypoxia and edema. Biofilm is present in 90% of chronic wounds and 6% of the acute ones. Biofilm is a corporative association of microbes which adhere to the surface of the wound, guided by quorum sensing molecules. The association is surrounded by a moisturizing matrix of extracellular polymeric substances (slime) which protect the microbes from the impact of antibiotics, antiseptics, macro-organism defense and stress. Biofilm is the primary cause of the wound chronicity because it causes permanent inflammation, delayed granulation tissue formation and migration of epithelium cells, thus providing a reservoir of microbes that lead to infection of the chronic wound. The aim of good clinical practice is to enable healing of a chronic wound within the expected time frame. In order to achieve this aim, it is necessary to reduce and thoroughly remove the biofilm from the wound and prevent its reappearance. This is achieved by the application of active anti-biofilm compounds and procedures that disintegrate the quorum sensing molecules, degrade the extracellular polymeric substances and block adherence to the surfaces. Recent researches have shown that the application of antiseptics is effective in the prevention of infection and is a support to targeted treatment. However, the fact is that only some antiseptics are applicable to chronic wounds and can have an impact on biofilms of the primary infective agents such as Staphylococcus spp., Streptococcus spp., and Pseudomonas aeruginosa. Effective antiseptics are octenidine dihydrochloride, polyhexanides, povidone and cadexomer iodine, nanocrystal silver and Manuka-type honey. Immobile biofilm is a persistent problem of chronic and chronic infected wounds. In fact, there is no isolated therapeutic procedure or an individual antiseptic that can fully destroy the biofilm. For this reason, modern strategy in the management of chronic wound applies a multimodal approach which combines mechanical-chemical procedures such as debridement, antiseptics, and antimicrobial supportive compresses. Debridement creates a therapeutic 'window' for the action of antiseptics and antibiotics in a 72-hour period, which enables removal of the biofilm and active destruction of the sessile and planktonic bacteria. This approach also prevents de novo formation of the biofilm. The above procedures must be intensively repeated, and antiseptics and supportive compresses changed, depending on the phase of the wound bed and comorbidity factors in the patient. The results of clinical studies show that only such a proactive approach to chronic wound enables achievement of healing within the expected period of time.
慢性伤口无法在预期时间内愈合,因为它一直处于愈合的炎症阶段。其原因在于存在坏死组织和大量微生物,主要是分泌生物膜的细菌,同时伴有局部缺血、缺氧和水肿。生物膜存在于90%的慢性伤口和6%的急性伤口中。生物膜是微生物的协作联合体,在群体感应分子的引导下附着于伤口表面。该联合体被细胞外聚合物(黏液)的保湿基质所包围,这保护微生物免受抗生素、防腐剂、机体防御和应激的影响。生物膜是伤口慢性化的主要原因,因为它会引发持续炎症、延迟肉芽组织形成以及上皮细胞迁移,从而提供导致慢性伤口感染的微生物库。良好临床实践的目标是使慢性伤口在预期时间内愈合。为实现这一目标,有必要减少并彻底清除伤口中的生物膜,防止其再次出现。这可通过应用活性抗生物膜化合物以及分解群体感应分子、降解细胞外聚合物并阻止其附着于表面的程序来实现。近期研究表明,应用防腐剂在预防感染方面有效,且有助于靶向治疗。然而,事实上只有一些防腐剂适用于慢性伤口,并且能对主要感染病原体如葡萄球菌属、链球菌属和铜绿假单胞菌的生物膜产生影响。有效的防腐剂有二盐酸奥替尼啶、聚己缩胍、聚维酮和碘仿糊剂、纳米晶银和麦卢卡型蜂蜜。固定的生物膜是慢性和慢性感染伤口的一个持续问题。实际上,不存在能完全破坏生物膜的单一治疗程序或单独一种防腐剂。因此,慢性伤口管理的现代策略采用多模式方法,将清创、防腐剂和抗菌支持性敷料等机械 - 化学程序结合起来。清创为防腐剂和抗生素在72小时内发挥作用创造了一个治疗“窗口”,这能够清除生物膜并有效杀灭固着和浮游细菌。这种方法还能防止生物膜重新形成。上述程序必须根据伤口床的阶段和患者的合并症因素重复进行,同时更换防腐剂和支持性敷料。临床研究结果表明,只有这种对慢性伤口积极主动的方法才能在预期时间内实现愈合。