Hydrogel dressing in comparison with hydrocolloid

Hydrogel dressing in comparison with hydrocolloidIntroductionWound repair may be divided into three overlapping phases, namely the inflammation granulation, and the matrix formation and re-modelling phases. In the inflammation phase, macrophages participate in the cleansing of the wound and are also responsible for initiating angiogenesis and the appearance of fibroblasts through the action of the cytokines they release. (Panchgnula and Thomas 2000 131-50) In the second phase of wound healing, granulation tissue appears, and consists mainly of fibroblasts which actively synthesize collagen precursors. These are deposited in the extracellular matrix, and crossed-linked to give tensile strength to the newly healed wound. The remodelling phase consists of the continuous resorption and resynthesis of collagen. It has been shown that re-epithelialization and dermal repair occur more rapidly when a wound is maintained in a moist rather than a dry condition. (Katzung 2004 160-240)A wide range of wound dressings have been developed on this basis, to provide an optimum microenvironment for wound repair. It was recently shown that Granuflex Hydrocolloid Dressing, which is widely used in the treatment of various types of wounds, extended the inflammation phase and delayed entry into the remodelling phase in full-thickness excised lesions on porcine skin. The chronic inflammatory reaction appeared to be a response to particulate matter released from the dressing. It has also been reported that bypergranulation occurs in some cases following the clinical use of Granufiex dressing. It has been suggested that enhanced wound angiogenesis associated with the use of Granutlex occurs because of wound hypoxia resulting from the relative impermeability of the dressing to oxygen. It has also been suggested that Granufiex dressing possesses fihrinolytic activity. (Panchgnula and Thomas 2000 131-50)DiscussionMost of the research on hydrocolloids has relied on the rheological analysis of

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