By the WoundSource Editors

In normal wound healing, exudate plays an important role in allowing the migration of cells across the wound bed, facilitating the distribution of growth and immune factors vital to healing. Managing wound drainage involves making sure that exudate production is not too much or too little, and making sure the exudate does not have pus which would indicate an infection. Proper wound drainage management improves the patient's quality of life, promotes healing, and enhances health care effectiveness.

What is Wound Exudate?

Exudate is mostly made from water, but it also contains nutrients, electrolytes, proteins, inflammatory mediators, growth factors, waste products, and a variety of cells such as platelets, macrophages, and neutrophils. The presence of microorganisms in wound drainage does not necessarily mean the wound is infected. Generally, wound drainage is odorless and looks like clear or pale yellow watery liquid. However, the type of wound drainage and the amount depends on the type of wound.

What are the Typical Problems with Wound Drainage?

The volume of wound drainage is determined by the surface area of the wound, so large wounds like skin donor sites or burns frequently have a much greater volume of wound drainage. However, as the healing progresses, the wound drainage of any size or type of wound usually decreases. Common problems are:

• Overproduction of exudate may signal bacterial contamination or inflammation (depending on the characteristics of the exudate).
• Too little exudate might indicate a systemic problem like shock or dehydration.
• In chronic wounds, too much exudate can sometimes impede healing by slowing down cell growth, degrading the extracellular matrix and causing periwound skin damage.

Why is it Important to Manage Wound Drainage?

Effective wound drainage management will improve a patient's quality of life by reducing dressing change frequency, shortening healing time and reducing problems with infection. Effective wound drainage management requires:

• Comprehensive assessment of the region of the wound and current dressing.
• Assessing the nature and amount of exudate, the wound base, periwound skin and edge of the wound.
• Choosing an appropriate dressing for an optimal moist wound environment.

When a wound has optimal wound drainage, the wound bed will have small amounts of fluid visible when the dressing is removed and will appear glossy and moist. The dressing may be lightly marked by the fluid when it is time for it to be changed. Surrounding skin will be intact, hydrated, and have no lesions. Signs of problems are:

• Too little wound drainage: wound bed has no visible moisture, the primary dressing is unmarked, dressing sticks to the wound, and surrounding skin is atrophic.
• Too much wound drainage: wound bed has free fluid visible, the dressing is wet or saturated, frequent changes required, and periwound skin may be macerated or denuded.

Strategies for Increasing Wound Moisture: If a wound has too little exudate, it is important to choose a dressing type which conserves or adds moisture. Occlusive dressings with a semi-permeable film backing, hydrocolloids, or hydrogels can increase wound moisture.

Strategies for Reducing Wound Moisture: Excessive wound exudate requires reassessment to make sure the appropriate treatments are in place, such as elevation or compression when appropriate. If possible, a suitable skin barrier and atraumatic dressings can help. Dressings made with gelling fibers such as CMC or chitosan form a gel that can prevent lateral movement of fluid that can protect periwound skin. Another technique is to use a thicker and more absorbent version of the current dressing, or change to a dressing which has a greater fluid capacity. Some dressing materials have different layers or pockets which can handle greater amounts of fluid. Consider adding a higher absorbency secondary dressing. In addition, it may be appropriate to increase the frequency of dressing changes.

Other Management Practices for Wound Drainage: Topical negative pressure wound therapy can been employed on wounds that are painful and have significant drainage. Fluid collection devices like stoma or urostomy bags can also be used if the surrounding skin area can support an adhesive flange. Skin protectants are essential when using any dressing or device that adheres to the skin, or there is risk of skin exposure to exudate.

How to Know When Wound Drainage Management is Successful

When the right choices have been made, the wound bed will be healthy and have no signs of infection, the periwound skin will be healthy and improving, there will be a reduced need for dressing changes and the patient will have less wound pain. Health care practitioners have the opportunity through regular and careful assessment of wound drainage to make sure that wounds are healing correctly. Good exudate management can make a significant contribution to preventing complications in wounds which can in turn increase the patient's level of comfort and quality of life.

The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.