The capacity of a product to draw exudate into itself is referred to as its “wicking” or its capillary action. Effective wicking is essential to moving wound exudate way from the wound and into the dressing. As a rule of thumb, dressings that “vertically wick” are preferred over dressings that “horizontally wick”. The action of vertical wicking is preferred as products that vertically wick hold wound exudate into the area of the dressing that is in contact with the exudate. This reduces the risk of the area around the wound (the peri wound) becoming macerated or wet. This is not the case with products that horizontally wick fluid.
The action of drawing and “holding” wound exudate within the product is known as it is locking or fluid handling capacity. Products that have locking capacity can hold wound exudate within the dressing even under pressure. Products designed to manage wound exudate vary in their fluid handling capacity resulting in variability in performance and wear time.
The fluid handling capacity of the dressing (mostly in the foam category) can be enhanced by the “breathability” of the product. The breathability refers to the rate at which moisture that is wicked into the dressing is evaporated away from the product. The measure of the passage of wound exudate through the outer layer of the product is known as the moisture vapour transmission rate (MVTR). As a rule, the higher the MVTR the more rapidly wound exudate moves through the product. MVTRs vary between products and brands, resulting in variability in the fluid handling capacity of individual products.
The fluid resistance of any product refers to its ability to repel fluid external to the product. In this context exudate management products that have a higher level of fluid resistance will be inherently be more waterproof, and products with lower levels, less so. Some exudate management products will be available in adhesive and non-adhesive variants. Adhesive dressings tend to be bordered and provide some level of fluid resistance. Non-bordered products require retention to secure the dressing and provide fluid resistance. For most products, fluid resistance means it might be possible to shower with a product in place, however bathing or swimming with dressings in place (even those that claim to be waterproof) is not advisable unless additional precautions have been taken to waterproof the dressing
These exudate management products are popular with clinicians as silicone is generally well tolerated and tends to be gentle on the skin. This means that is can be easily removed without causing pain or trauma. For this reason, silicone WCLs are very popular in dealing with fragile skin. This said, silicone is by nature hydrophobic (fluid repellent) so silicone WCLs need to be punctured with holes (fenestrated) in order to take fluid up. Because of this, silicone WCL dressings are best used on wounds with low to moderate levels of exudate.
These products tend to provide a more abrasive adhesion but do so at the expense of patient comfort as dressings with this type of WCL can be painful to remove. Water based adhesives are made of acrylic resin polymers and produce a clear flexible bond on contact with the patient’s skin. Water based adhesive WCLs will “break” when in contact with water, causing the dressing to fall away.
Non adhesive dressings have no adhesive properties and as such require some form of secondary retention to hold the dressing in place (often referred to as secondary retention). Forms of secondary retention include tapes or bandaging. These dressings tend to manage wound exudate well as the absorbent layer (foam) is in direct contact with the wound bed.
Note that fluid laterally migrates up the dressing and that fluid can easily be pressed out of the dressing under gentle pressure
Note that fluid is vertically wicked and locked into the dressing and cannot be removed through the application of gentle pressure.
Note that fluid is vertically wicked and locked into the dressing. Note also that due to the silicone wound contact layer that the fluid is slower on the uptake than other dressings designed to handle wound exudate.
Note that fluid is vertically wicked and locked into the dressing. Note also that fluid uptake for this category of dressing is rapid and as such can be useful for wounds with higher levels of exudate.
Demonstration of monofilament pad to mechanically debride non viable tissue and hyperkeratosis
This editable T.I.M.E.S chart has been developed to enable you to enter the wound care products that you have available into the relevant "products" section of the chart. Ensure mode of action for each product is correct prior to populating the chart. Some products - e.g, Iodosorb, may be applicable over multiple components. Review generic T.I.M.E.S category allocation chart prior to populating.