Dear Abdelfatah,

I think that you are using the best method; an example of this is Hydrofiber® technology. Such dressings have been demonstrated to be clinically effective and cost-effective in exudate management, even when used under compression [29] [30].

Other methods used are described below:

http://www.worldwidewounds.com/2006/september/White/Modern-Exudate-Mgt.html#methods-used

Methods used to manage exudate

Dressings

If dressings are indicated, then prudent selection and careful determination of wear time are imperative. This will help ensure an optimal moist environment is maintained, while protecting the surrounding skin from maceration [23] [24].

Certain key performance characteristics are required for any such dressing: they must absorb and retain exudate, keep harmful chronic wound exudate away from the surrounding skin, perform efficiently when used under compression, be easy to remove and be demonstrated as cost-effective.

Wound dressings exhibit various fluid-handling mechanisms: absorption, gelling, retention and moisture vapour transmission. Information on a dressing’s fluid-handling mechanism is available from the manufacturers. This information may not always be based on accepted, independent test methodologies, but rather on in-house laboratory data, which is invariably favourable to manufacturers’ own products. There are standard test methods, published as monographs in various pharmacopoeias and in peer-reviewed journals that provide independent, objective data on dressing fluid handling [25]. The basic dressing mechanisms are as follows:

Absorption

Exudate is absorbed into the dressing matrix. In the case of some foam dressings, this is a reversible mechanism; the fluid can be expressed from the dressing under pressure. Not all foams behave in this fashion.

Gelling

Following absorption, the exudate interacts with the dressing material to form a gel [26]. This is a typical attribute of alginates: these carbohydrate polymers gel according to the proportion of uronic acid units in their composition [27]. However, with alginate gels, fluid may come into contact with the peri-wound skin [27]. This can also occur with hydrocolloid gel, the degree being dependent on polymer composition [28].

Fluid retention

In dressings with this mechanism, fluid is absorbed by the dressing and is no longer available to wet the surronding skin. Such materials retain the absorbed fluid directly above the wound, without sideways spread or ‘lateral wicking’. An example of this is Hydrofiber® technology. Such dressings have been demonstrated to be clinically effective and cost-effective in exudate management, even when used under compression [29] [30].

Moisture vapour transmission

In recent years dressings have been designed to absorb fluid and, via an intermediate ‘wicking’ layer, move fluid away from the wound/skin interface towards a permeable backing layer. Here, some fluid is lost to the atmosphere by evaporation, a process known as moisture vapour transmission. This mechanism is intended to increase the fluid-handling capacity of the dressing [31] [32]. The success of this process depends upon the proportion of absorbed fluid that is lost. Evaporation will be compromised by the presence of occluding materials, such as compression bandages, which may reduce evaporation rates. There are no clinical data to suggest that this works in practice. Indeed, some clinicians are sceptical that it has any performance-enhancing value [33].

Antimicrobial properties

Dressings with an antimicrobial component are intended for the control of the wound bioburden in critical colonisation and local infection [34]. These dressings are useful, therefore, where raised exudate levels are attributed to bacterial causes. There is also justification for their use in cases of spreading infection where systemic antibiotics have been used and impaired perfusion is suspected [35] [36]. Typical antimicrobial dressings are those containing silver, iodine or honey [12] [35] [37].

29. Armstrong SH, Ruckley CV. Use of a fibrous dressing in exuding leg ulcers. J Wound Care 1997; 6(7): 322-4.

30. Guest JF, Ruiz FJ, Mihai A, Lehman A. Cost effectiveness of using carboxymethylcellulose dressing compared with gauze in the management of exuding venous leg ulcers in Germany and the USA. Curr Med Res Opin 2005; 21(1): 81-92.

Hoping this will be helpful,

Rafik

 Thank you Rafik Karaman,

I understand, but I need the most reliable technique or test used to test the MMPs that present or strongly associated with such chronic wounds? However, we use NPWT for both control cases and study cases in addition to the collagen based matrix that we use for study group.

I hope you understand what I need?

the best way to test fluid for Mmp2 and 9 is to take the fluid and add FRET substrates and measure fluorescence. Tiny amounts of fluid cane be used. See my publications and those of Miles A. Miller on Researchgate. We have selective Mmp2 and Mmp9 substrates which you can use minus and plus specific inhibitors. See publication also by Ee Xien.

Cool,

Thank you so much Marcia Moss. :)