Foam dressings are absorbent dressings that can be used on wounds that produce low to high levels of wound fluid (also known as exudate).
They absorb exudate to prevent it from damaging the wound and surrounding skin (the periwound area).
Simple foam dressings allow fluid to pass straight through them, acting like a sponge. Once the dressing is saturated, or if pressure is applied, fluid will leak through (known as strikethrough).
More sophisticated products absorb fluid into the structure of the dressing, a process known as wicking. Wicking spreads fluid through the dressing, giving it greater absorbency than simple foams.
Foam dressings that absorb low levels of fluid may be known as ‘lite’ or ‘thin’, while those that hold higher volumes may be called ‘plus’ or ‘super’.
Not all foams are the same: the amount of fluid absorbed by a foam dressing varies from product to product.
There are many foam products available, how do I select the right one?
Each patient has different needs that need to be considered when choosing the correct product. The following questions can help with dressing selection.
How much exudate is the wound producing?
If the wound is producing medium to high volumes of exudate, a plus or super product may be required. However, if exudate production is low, a lite or thin dressing may be more suitable. Correct exudate assessment (based on colour and amount and management is essential both to maintain a moist wound healing environment and to prevent the periwound skin from maceration. There are several methods available for assessing exudate, such as Falanga (2000), the Bates-Jensen wound assessment tool, (Bates-Jensen, 2007), and a proposed national wound assessment form (Fletcher, 2010), that uses the term ‘wound moisture level’ rather than exudate, and is based on the World Union of Wound Healing Societies (WUWHS) document on exudate (WUWHS, 2007). Clinicians should also refer to their own local policy on how to assess exudate volume.
How fragile is the patient’s skin: adherent or non-adherent?
Non-adherent foam dressings do not stick to the skin and so need to be secured in place by another dressing such as tape or light retention bandages. These dressings are suitable for use on fragile or damaged skin, where adhesive dressings may result in skin damage.
Adherent foams have an adhesive backing so that they stick directly to the skin without needing to be held in place by other products.
Is the dressing going to be used under compression?
Some foams cannot hold fluid under pressure. This means that if pressure is applied, such as by compression bandaging, or by body weight if the dressing is placed on the sacrum or heel, the fluid in the dressing may leak out. In such circumstances, dressings which have the ability to wick and lock fluid away should be used.
Some foams have a film-backing which prevents fluid leaking out of the back, which could prevent bandages or other dressings used to fix them in place from becoming wet.
Is antimicrobial action needed?
Some foam dressings have antimicrobial components which help the dressings to kill microorganisms that may be responsible for local wound infection or delayed healing. Antimicrobial dressings should only be used if infection is present, or if the patient is considered to be at an increased risk of wound infection.
Does the wound need protection?
Foams can also be used to protect boney prominences as they can provide cushioning, preventing the skin/wound from further damage. However, they do not relieve pressure so should not be used in place of pressure-relieving products.
Where is the wound? Is it in a place that is difficult to dress?
Some wound sites such as the sacrum or heel can be difficult to dress. There are ranges of foam dressings that have specifically designed dressings for such anatomical areas.
Selection of a foam dressing should be guided by:
- Volume of exudate
- Condition of skin
- Location of wound
- Use under compression
- Presence of infection.
Although cost-effectiveness is important, choosing the cheapest foam is not necessarily the best thing to do, as dressing choice should always be guided by the patient’s needs. If a dressing fails to perform well, more frequent dressing changes will be needed, incurring greater nursing time.
Patient choice and preference should always be considered. This helps to build up a good nursing–patient relationship and is in line with national policy.
- Fluid-handling capacity
- Film backing
- Secondary dressing required
- Can be used under compression
Bates-Jensen B (1997) The pressure sore status tool a few thousand assessments later. Adv Wound Care 10(5): 65–73
Falanga V (2000) Classifications for wound bed preparation and stimulation of chronic wounds. Wound Rep Regen 8(5): 347–52
Fletcher J (2010) Development of a new wound assessment form. Wounds UK 6(1): 92–9
World Union of Wound Healing Societies (2007) Principles of Best Practice: Wound Exudate and the Role of Dressings. A Consensus Document. Available online.