VOL: 102, ISSUE: 16, PAGE NO: 37
Jacqui Fletcher, MSc, PGCertEd, RGN
principal lecturer, tissue viability, Department of Nursing and Midwifery, University of HertfordshireVapour-permeable films
Vapour-permeable films are thin, transparent, semi-permeable products. They are waterproof but allow small amounts of moisture to evaporate from the wound, a process known as moisture vapour transpiration (MVTR). The extent of 'breathe off' varies between brands. Although the films allow transmission of water vapour and oxygen they are impermeable to microorganisms.
Indications for use
Films dressings are used for shallow wounds that have a minimal amount of exudate, such as postoperative wounds, grazes and abrasions. They are also used over fragile areas of skin to protect them from friction or moisture damage. In addition to their use as a primary dressing, film dressings are often used to hold a primary dressing in place.
Only one company manufactures a non-sterile film specifically for this purpose, and it is produced in rolls similar to tape. This is more cost-effective than using a sterile product when it is not in direct contact with the wound.
Some film dressings have other components, such as the addition of an absorbent pad, which allows them to be used on wounds that are producing a small amount of exudate. They are also available with a central alginate pad for increased absorbency. One manufacturer has incorporated an antimicrobial - silver - into its film dressings. These products have a darker, greyish colour.
Application and removal
The different films all have different release mechanisms for removing the backing from the adhesive film and this can have a bearing on how easy it is to use the product. It is important always to read the product literature before application and removal of the dressings.
Film dressings are flexible and easy to apply, but must be removed carefully to prevent the stripping of tissue from the epidermis. The dressing should be stretched from the edge to break the adhesive bond rather than peeled back.
Some film dressings also have an additional grid layer, which allows the outline of the wound to be traced. The grid is then peeled off and stored in the patient's notes, thereby assisting in the evaluation of wound healing.
Jacqui Fletcher, MSc, PGCertEd, RGN, is principal lecturer, tissue viability, Department of Nursing and Midwifery, University of Hertfordshire