The previously accepted wisdom was that a wound healed best when it was kept as dry as possible. In 1962, George Winter, a British-born physician, published his ground-breaking wound care research. His paper, (Nature 193:293. 1962), entitled, “Formation of the scab and the rate of epithelization of superficial wounds in the skin of the young domestic pig,” demonstrated that wounds kept moist healed faster than those exposed to the air or covered with a traditional dressing and kept dry. Dr. Winter’s work began the development of modern wound dressings which are used to promote moist wound healing.
Natural skin is considered the ideal wound dressing, and therefore wound dressings have been designed to try to reproduce the advantages of natural skin. Today, experts feel that a wound dressing should have several characteristics if it is to serve its purpose. A wound dressing should:
- Provide the optimal moisture needs for the particular wound
- Have the capacity to provide thermal insulation, gaseous exchange, and to help drainage and debris removal, which promotes tissue reconstruction
- Be biocompatible without causing any allergic or immune response reaction
- Protect the wound from secondary infections
- Be easily removable without causing any trauma to the delicate healing tissues.
There are hundreds of dressings to choose from, but they all fall into one of a few categories. The healthcare provider will select a dressing by category, according to availability and familiarity of using that particular dressing.
Occlusive dressings are those which are air- and water-tight. An occlusive dressing is frequently made with some kind of waxy coating to ensure a totally water-tight bandage. It may also consist of a thin sheet of plastic affixed to the skin with tape. An occlusive dressing retains moisture, heat, body fluids and medication in the wound. There are several types of occlusive dressings, which are discussed below.
It should be remembered that proper wound care, especially of a chronic wound, is a complex process, as much art as science; a trained healthcare provider assesses the wound as it goes through various stages, and applies the appropriate wound dressings as the need arises. Unfortunately, the most appropriate dressing is not always used, due perhaps to confusion around which type of dressing to apply, or because certain dressings—especially advanced dressings—either may not be available in the facility, or may not be reimbursed by the country’s healthcare system, or may simply be too expensive. This remains true even in some of the developed countries.
The following table summarizes potential applications for various types of wound care products, with selected examples. This summary is meant as a guideline and an illustration of the fact that different dressing types may find use in various types of wounds. In addition, as a wound heals, it may need a different type of dressing. Here again the wound care professional’s judgment and training come into play.
|Dressing category||Product examples||Description||Potential applications|
|Film||Hydrofilm, Release, Tegaderm, Bioclusive||Comes as adhesive, thin transparent polyurethane film, and as a dressing with a low adherent pad attached to the film.||Clean, dry wounds, minimal exudate; also used to cover and secure underlying absorptive dressing, and on hard-to-bandage locations, such as heel.|
|Foam||PermaFoam, PolyMem, Biatain||Polyurethane foam dressing available in sheets or in cavity filling shapes. Some foam dressing have a semipermeable, waterproof layer as the outer layer of the dressing||Facilitates a moist wound environment for healing. Used to clean granulating wounds which have minimal exudate.|
|Hydrogel||Hydrosorb Gel Sheet, Purilon, Aquasorb, DuoDerm, Intrasite Gel, Granugel,||Colloids which consist of polymers that expand in water. Available in gels, sheets, hydrogel-impregnated dressings.||Provides moist wound environment for cell migration, reduces pain, helps to rehydrate eschar. Used on dry, sloughy or necrotic wounds.|
|Hydrocolloid||CombiDERM, Hydrocoll, Comfeel, DuoDerm CGF Extra Thin, Granuflex, TegasorbÕ Nu-Derm||Made of hydroactive or hydrophilic particles attached to a hydrophobic polymer. The hydrophilic particles absorb moisture from the wound, convert it to a gel at the interface with the wound. Conforms to wound surface; waterproof and bacteria proof.||Gel formation at wound interface provides moist wound environment. Dry necrotic wounds, or for wounds with minimal exudate. Also used for granulating wounds.|
|Alginate||AlgiSite, Sorbalgon Curasorb, Kaltogel, Kaltostat, SeaSorb, Tegagel||A natural polysaccharide derived from seaweed; available in a range of sizes, as well as in ribbons and ropes.||Because highly absorbent, used for wounds with copious exudate. Can be used in rope form for packing exudative wound cavities or sinus tracts.|
|Antimicrobial||Biatain Ag, Atrauman Ag, MediHoney||Both silver and honey are used as antimicrobial elements in dressings.||Silver: Requires wound to be moderately exudative to activate the silver, in order to be effective|
|NPWD||SNaP, V.A.C. Ulta, PICO, Renasys (not in USA), Prospera PRO series, Invia Liberty||Computerized vacuum device applies continuous or intermittent negative or sub-atmospheric pressure to the wound surface. NPWT accelerates wound healing, reduces time to wound closure. Comes in both stationary and portable versions.||May be used for traumatic acute wound, open amputations, open abdomen, etc. Seems to increase burn wound perfusion. Also used in management of DFUs. Contraindicated for arterial insufficiency ulcers. Not to be used if necrotic tissue is present in over 30% of the wound.|
|Bioengineered Skin and Skin Substitutes||AlloDerm, AlloMax, FlexHD, DermACELL, DermaMatrix, DermaPure, Graftjacket Regenerative Tissue Matrix, PriMatrix, SurgiMend PRS, Strattice Reconstructive Tissue Matrix, Permacol, EpiFix, OASIS Wound Matrix, Apligraf, Dermagraft, Integra Dermal Regeneration Template, TransCyte||Bio-engineered skin and soft tissue substitutes may be derived from human tissue (autologous or allogeneic), xenographic, synthetic materials, or a composite of these materials.||Burns, trauma wounds, DFUs, VLUs, pressure ulcers, postsurgical breast reconstruction, bullous diseases|
Source: MedMarket Diligence, LLC; Report #S251.