Alginate Dressing: Benefits, Uses, and Best Practices

Selecting the appropriate dressing can make a huge difference in your patients’ quality of life and recovery time. Known for its ability to support healing by managing moisture, an alginate dressing may be the best option.

Do you have a favorite type of wound dressing? For many wound care clinicians, including myself, a tried-and-true dressing type is an alginate dressing.

Alginate is quite a useful dressing, but it’s not the right choice for all wounds. Let’s look further into this handy dressing, including when and how to use it.

What is an alginate dressing?

Alginate dressings, also known as calcium alginate dressings, consist of sodium and calcium fibers sourced from the cell walls of brown seaweed. Calcium salt from seaweed contains cellulose-like polysaccharide fibers.

This creates a soft, wound dressing that is highly conformable to the body. The dressing is non-toxic and biocompatible. And research from the National Library of Medicine further breaks down calcium alginate dressing’s make up and function to a cellular level.

How does a calcium alginate dressing work?

When calcium in the alginate dressing becomes exposed to wound drainage, the fibers within the dressing swell. As the fibers expand, they create a soft gel.

This gelatinous consistency helps ensure an adequate wound bed environment that is favorable to wound healing. It also allows the dressing to absorb wound exudate which will help protect the wound edges from maceration and breakdown.

Benefits of using this dressing

When used appropriately, a calcium alginate dressing can have many benefits. And one of the most beneficial uses is the dressing’s ability to absorb and contain large amounts of exudate.

Alginate dressings can hold a lot of fluid (many times absorbing 20 to 30 times their dry weight), making them an excellent choice for high output wounds. Controlling wound exudate will contribute to a healing environment as well as preserve the wound edges from break down. This is important because once wound edges become macerated and begin to break down, the wound essentially becomes bigger and is more difficult to treat.

Another benefit of using an alginate dressing is its ability to facilitate autolytic debridement. When used properly, the warm, moist wound bed created by these dressings encourages the decomposition of necrotic tissue. Of course, this is a slower process than a sharp debridement, but it’s very useful when pain or other issues prohibit sharp debridement. A warm, moist environment is necessary for wound healing.

The gelatinous consistency of a calcium alginate dressing when hydrated by wound exudate is conforming, comfortable, and nonadherent. The dressing’s ability to decrease pain and discomfort due to this consistency, should be considered when choosing a dressing type. Alginate dressings can also assist with infection control by facilitating autolytic debridement and by trapping bacteria in its dense fibers.

In addition, calcium alginate dressings are available in a silver option. Silver alginate has silver ions within its fibers. This is an effective option for wounds that are infected or at high risk of infection. This silver dressing type provides the same benefits as regular calcium alginate but with the added benefit of infection control and prevention.

Contraindications to consider

A calcium alginate dressing should not be used on a dry or minimally draining wound. Using calcium alginate on low-draining wounds will overly dry out the wound bed resulting in a stall of the healing process.

Desiccation of the wound tissues can also lead to pain with dressing changes and potentially create an environment that is susceptible to infection. Additionally, do not use silver calcium alginate on patients with a known sensitivity to silver products.

Appropriate uses

Calcium alginate dressings is used on most wound etiologies. Due to its conformability, an alginate dressing is an option for irregularly shaped wounds and wounds with varying levels of depth.

For wounds with tunnels that can be completely explored, use woven, rope alginate. And on wounds with moderate to heavy drainage, use calcium/silver alginate dressings. Calcium alginates are also beneficial if you’re looking for dressing longevity.

How to use an alginate dressing: A guide for clinicians

After cleansing the wound, apply dry calcium or silver alginate to the wound, ensuring good contact with the wound bed as well as any areas of undermining. As mentioned earlier, alginate dressings will develop a gel-like consistency when exposed to wound exudate.

For wounds with excessive output, a temporary daily dressing change may be required until drainage is better controlled or slows. This may require treatment of any signs or symptoms of infection and/or treatment of lower extremity edema. Frequent dressing changes may be required temporarily in the following scenarios:

• To preserve periwound skin
• To sustain an optimal wound environment
• To preserve the function of the dressing (for highly exuding wounds)

As drainage decreases, the need for frequency of dressing changes lessens. A wound suited for an alginate dressing may continue to require two to three weekly dressing changes. These dressings last up to seven days if drainage is well controlled.

Choosing a secondary dressing to use over the alginate will depend on the needs of the wound. Do you need to control drainage, encourage autolytic debridement, or protect the wound from pressure, friction, and shearing? Gauze, film, and foam dressings are a few common secondary dressings that will support these goals.

When removing an alginate dressing, gently remove the secondary dressing and cleanse the wound. Carefully remove any leftover pieces from the wound bed or periwound skin.

However, if the alginate remains mostly intact, dry, or stuck to the wound bed or periwound tissue, this indicates a need to reevaluate the use of calcium alginate. In these situations, it is likely that the wound does not have adequate drainage to support the use of a calcium alginate dressing.

Alginate dressings are incredibly versatile. You can use them on a high drainage venous ulcer or use silver alginate for a pressure injury of the tailbone to assist with infection prevention. There are many ways to use this dressing and many types of wounds that benefit.