Wound Dressing

Wound dressing types

Please use the links below to jump to the relevant section

Semi-permeable dressings

These clear films cover the wound and are permeable to water vapour and oxygen but impermeable to water and micro-organisms. The film acts as a barrier to bacteria attempting to enter the wound. Film dressings are convenient to use, comfortable and enable the wound to be observed at all times. These dressings are a useful for sealing a primary dressing and can be used as a protective cover to prevent skin breakdown from friction. They should not be used for friable ’tissue type’ skin, cavity wounds, third degree burns or infected wounds. Not suitable for exudating wounds.the wound and are permeable to water vapour and oxygen but impermeable to water and micro-organisms. The film acts as a barrier to bacteria attempting to enter the wound. Film dressings are convenient to use, comfortable and enable the wound to be observed at all times. These dressings are a useful for sealing a primary dressing and can be used as a protective cover to prevent skin breakdown due to friction. They should not be used for friable “tissue type” skin, cavity wounds, third degree burns or infected wounds. Not suitable for exudating wounds.

Wound contact dressings

We recommend that silicone-based products are used as they do not adhere to the wound surface and can be left in place for 7 days.

Foam dressings

These products are easily shaped to a wound and help to keep the wound surface moist. They are permeable to water vapour and oxygen and can absorb significant quantities of exudate.

Alginate dressings

Alginates are found naturally in various species of brown seaweed from which they are extracted for dressing production. These products consist of either calcium alginate alone, which is insoluble, or a mixture of calcium and sodium alginates, the other sodium alginate being soluble. By varying the proportions of the two salts, gels can be produced when they come into contact with exudate. They are useful for treating heavily exuding wounds including leg ulcers, pressure sores, donor sites and, due to their haemostatic properties, the management of bleeding wounds.

Hydrogel dressings

Hydrogels consist of insoluble polymers which have a hydrophilic nature. When mixed with aqueous solutions, they will absorb large volumes of liquid. There are currently two types of product in use. One group is presented as sheets of material that consist of polymers with a rigid three-dimensional structure. These sheets swell as they absorb fluid. The second group are amorphous without a fixed macro structure; as they absorb fluid they reduce in viscosity and start to flow so that they can take up the wound shape.

They are suitable for desloughing and for treating light to medium exudating wounds. Hydrogels promote rapid debridement of necrotic wounds, and by preventing desiccation they facilitate re-epithelialisation and minimise scar formation in granulating wounds.

Hydrocolloid dressings

These dressings consist of gel forming agents to which have been added adhesives, elastomers and sometimes proteins. They are presented as a flexible sheet which is coated with a layer of the hydrocolloid base and covered with a piece of release paper. These dressings have occlusive properties. They are also valuable in treating pressure areas. They are best suited to wounds which do not produce excessive quantities of exudate.

Hydrocolloids can be used to treat pressure sores, leg ulcers, minor burns, donor sites and many other types of granulating wound.

Maggot therapy

This is not a new therapy – as far back as the Napoleonic Wars maggots were found in soldiers’ wounds. This 'biosurgical' approach has recently become more popular. The larvae thrive on sloughy and necrotic tissue and burrow into it. A powerful enzyme is produced that can irritate healthy skin therefore maggot therapy must be applied by appropriately trained staff.

Capillary action dressing

This is a non-woven, four-layer non-adherent dressing, which comprises a 100% polyester outer layer, 80% polyester inner layer with 20% cotton fibres. The non-adhesive, non-adherent nature of the micro-fibres of the dressing ensures that no fibres are shed onto the wound surface. The non-woven outer layers are able to transport, lift and hold exudate by capillary action. The woven inner layer prevents a ’strike-through' by allowing the exudate to move across the fabric rather than straight through (dispersion technology). The inner and outer layers combine to draw the exudate away from the wound surface. This action lessens the risk of infection by removing harmful bacteria and prevents maceration of the wound. This dressing is non-interactive and suitable for the majority of wounds (including acute, trauma, surgical, chronic, burns, leg ulcers, and pressure sores). Although the dressing is highly absorbent, it is possible if required, to increase its absorption for wounds producing extreme volumes of exudate by applying a second layer over the first layer.

When initially using this dressing on a patient, it will be required to be changed on a daily basis. It will also need to be cut to the shape of the wound, and if the wound is long or deep, it may need to be laid in strips. Once the exudate has settled down it may be changed less frequently, possibly every two or three days. This enables the natural healing process to take place at a faster rate as there is no excess exudate at the wound interface.

Hydrofiber

This is a 100% sodium carboxymethylcellulose hydrocolloid polymer dressing. It absorbs and retains fluid by trapping it within the fibres, which then swell to form a soft, non-adherent cohesive gel. It has a high cohesive dry and wet tensile strength and absorbs up to 25 times its weight in fluid without losing its integrity. This hydrocolloid polymer is spun into fibres and is manufactured into ribbon and sheet formats.

Hydrofiber absorbs fluid by hydrophilic action, directly into the fibre structure, locking exudate away from the peri-wound skin and thus reducing the risk of maceration. Sequestration, the locking away of harmful bacteria, also occurs due to this hydrophilic action. Once the Hydrofiber has turned into a gel-sheet it covers the surface of the wound by moulding itself over the contours, thus maintaining an optimal, warm, moist wound healing environment.

Carbon dressing/Charcoal dressing

Charcoal dressings are used in the management of malodorous wounds. Activated charcoal cloth is produced by carbonising a suitable fabric by heating it under carefully controlled conditions. The surface of the carbon breaks down to form small pores, which greatly increase the surface area of the fibre and hence the ability to control odours. The molecules responsible for malodour are attracted to the surface of the carbon and held there by electrostatic forces. Charcoal dressings vary considerably in their properties, design and ability to handle exudate. For information on specific dressings, please refer to the manufactures for information.

Honey dressings

Honey has been employed in wound care since Egyptian times and over the last few years there has been resurgence in its use. Honey has been shown to be effective against bacteria, aerobes, anaerobes, gram positive and gram negative bacteria and resistant strains of Streptococcus pyogenes and Staphylococcus aureus.

It works by producing low concentrations of slow release hydrogen peroxide found naturally in honey and its high osmolarity inhibits bacterial action but the mechanism by which honey influences wound healing processes is not fully understood. The application of honey facilitates wound bed preparation through the process of autolytic debridement.

Honey dressings should not be used on patients with diabetes because the glucose and fructose can be absorbed through the open wound.

Honey dressings are available in sheet or gel format and should be covered with a secondary dressing depending on the exudate level.

Silver dressings

There has been a resurgence of interest in the use of silver for its anti-bacterial properties in wound care. Silver sulphadiazine has been used successfully to treat burns and control infection. The chemical bonding of silver with sulphonamide has resulted in a safe, broad spectrum agent for topical use. Silver is released slowly from the oil in cream formulations in concentrations that are selectively toxic to micro-organisms such as MRSA.

The silver reacts in the presence of moisture, body fluids and wound exudate to release silver ions in a process known as hydro activation. The concentration of silver ions released is proportional to the antiseptic efficacy of the product. Silver in various formulations can be used for patients with infected wounds and as prophylactic treatment.