A leg ulcer is an open sore on the lower leg that fails to heal over a period of several weeks despite standard treatment. A “weeping” leg ulcer is specifically characterized by the production of excessive wound fluid, known as exudate. This copious drainage is often a result of underlying conditions like chronic venous insufficiency, where high pressure in the leg veins causes fluid and proteins to leak into the surrounding tissue. The goal of care is to select highly absorbent dressings that manage this fluid effectively, preventing complications and creating an optimal healing environment.
Understanding the Weeping Leg Ulcer
The primary challenge of a weeping leg ulcer is the sheer volume of exudate. While exudate contains growth factors necessary for healing, chronic wound fluid often contains inflammatory molecules that slow the process. If the fluid pools on the skin, it causes maceration, making the surrounding skin soft, white, and fragile.
Maceration makes the healthy periwound skin vulnerable to breakdown, potentially increasing the ulcer’s size and raising the risk of infection. Low-absorbency dressings are quickly overwhelmed by heavy weeping, leading to leakage and frequent changes. Therefore, the appropriate dressing must have a high fluid-handling capacity to absorb and lock the exudate away from the skin surface, which is essential for successful healing.
Primary Dressing Categories for High Exudate
Selecting a dressing for a weeping ulcer requires materials engineered specifically for high absorbency and fluid retention. The main categories include alginates, high-absorbency foams, and superabsorbent polymers, each utilizing a distinct mechanism to manage heavy drainage. These advanced dressings promote a moist wound bed, which facilitates faster healing than a dry environment.
Alginates and Hydrofibers
Alginate dressings are derived from brown seaweed and are composed of fibers containing calcium and sodium. When the dressing contacts exudate, the fibers transform into a soft, hydrophilic gel. This gel conforms to the wound bed, making it useful for deep or irregularly shaped ulcers, and can assist in initial blood clotting.
Hydrofiber dressings are similar but are made from sodium carboxymethylcellulose (CMC), which quickly gels upon contact with exudate. The gel formed by both types effectively traps the fluid, preventing it from spreading laterally and causing maceration of the surrounding skin. These dressings are used as a primary layer directly on the wound surface and require a secondary dressing for coverage and security.
Foam Dressings (High Absorbency)
High-absorbency foam dressings are polyurethane materials designed with an open-cell structure that allows for the rapid wicking and storage of fluid. They manage moderate to high levels of exudate while providing cushioning and thermal insulation. Many modern foam dressings are multilayered, featuring a contact layer, an absorbent foam core, and a breathable, waterproof outer film.
Foam dressings manage fluid partly due to their high moisture vapor transmission rate, allowing some absorbed water to evaporate through the backing. These dressings are available with or without an adhesive border, making them versatile for securing to the leg. They can often be left in place for several days if exudate levels permit.
Superabsorbent Polymers (SAPs)
Superabsorbent polymer (SAP) dressings are specialized for managing extremely heavy drainage. The core contains polymers that absorb and retain a volume of fluid many times their own weight, locking the exudate into a gel form. This mechanism minimizes the risk of fluid leaking out under pressure, which is relevant when compression bandages are applied to a leg ulcer.
SAPs are typically used as a secondary dressing placed over a primary layer, or they can be integrated into the primary dressing structure. Their main benefit is extended wear time, which reduces the frequency of dressing changes and minimizes disturbance to the healing wound bed.
Key Considerations for Dressing Selection and Change Frequency
Dressing selection relies on a clinical assessment of the ulcer’s exudate level. The dressing’s fluid-handling capacity must match the wound’s output; a mismatch can lead to maceration from under-absorption or wound bed desiccation from over-absorption. If the ulcer is heavily weeping, the dressing may require changing daily or even twice daily initially to prevent saturation and keep the periwound skin dry.
As exudate production decreases, the frequency of dressing changes can be reduced, often to every three to seven days. Reducing change frequency is beneficial because each change can disturb healing tissue and temporarily lower the wound bed temperature, slowing cellular repair.
Securing the absorbent primary layer usually requires a cohesive bandage or retention tape. A firm compression bandage is often applied over the dressing, as this is the standard treatment for the underlying venous insufficiency. Compression reduces swelling and fluid leakage from the veins, which directly helps manage the exudate level.
Preventing maceration requires protecting the periwound skin. Barrier creams or specialized films should be applied to create a protective, breathable layer. This layer shields the skin from constant exposure to moisture and irritants in the exudate, allowing healthy skin to remain intact and support the healing process.
When Professional Intervention Becomes Necessary
Managing exudate is crucial, but certain signs indicate that the current regimen is insufficient and requires immediate medical attention. A healthcare professional must address the underlying cause of the ulcer, such as venous disease, for true healing to occur. If the ulcer fails to show signs of improvement after two weeks of consistent dressing management, a consultation is necessary.
Signs of a spreading infection are concerning and require urgent medical intervention. These include:
- Significantly worsening pain or a sudden increase in swelling.
- A high temperature (fever).
- A foul odor or a discharge that is green or noticeably unpleasant.
- Redness around the ulcer that begins to spread or streaks up the leg, which may indicate cellulitis.