Wound Exudate: Fluid produced by a wound as part of the inflammatory and healing response. It contains water, proteins, electrolytes, inflammatory mediators, cells, enzymes, and other substances involved in tissue repair. Its amount and characteristics can provide important information about the wound environment.

Serous Exudate: Thin, clear, amber, or straw-colored wound fluid. Serous exudate can be expected during normal inflammation and tissue repair, although an unexpected increase in volume may warrant further assessment.

Serosanguineous Exudate: Thin wound drainage containing both clear fluid and a small amount of blood, giving it a pink or light-red appearance. It may be expected during certain stages of healing, particularly following surgery or minor tissue trauma.

Sanguineous Exudate: Wound drainage composed primarily of blood and therefore typically red in appearance. It may occur with new blood vessel formation or tissue trauma, but new or increasing sanguineous drainage should be evaluated in the context of the wound and the patient.

Purulent Exudate: Thick, opaque, or milky wound drainage that may appear yellow, tan, brown, or green. Purulent drainage is an important clinical finding associated with wound infection and should prompt further assessment.

Exudate Viscosity: The thickness or resistance to flow of wound exudate. Exudate may range from thin and watery to thick and viscous; changes in viscosity can provide clues about the wound environment and can also affect how well a dressing handles fluid.

Periwound Skin: The skin immediately surrounding a wound. Its condition is an important part of wound assessment because prolonged contact with excessive exudate can damage the skin and interfere with effective wound management.

Maceration: Softening and breakdown of skin caused by prolonged exposure to excessive moisture. In wound care, maceration commonly occurs when exudate remains in contact with the wound edges or periwound skin.

Moisture Balance: A wound environment in which sufficient moisture is maintained to support healing without allowing excess fluid to accumulate and damage the wound or surrounding skin. Both excessive and insufficient moisture can interfere with healing.

Autolytic Debridement: The body’s natural process of using endogenous enzymes and moisture to soften and remove devitalized or nonviable tissue from a wound. Maintaining an appropriately moist wound environment can support this process.

Biofilm: A structured community of microorganisms that attaches to a surface and becomes enclosed within a protective matrix. In chronic wounds, biofilm can contribute to persistent inflammation and stalled healing and may be difficult to identify by visual assessment alone.

Bioburden (Microbial Burden): The number and types of microorganisms present in or on a wound. Increasing microbial burden may contribute to inflammation, infection, changes in exudate, and delayed wound healing.

Matrix Metalloproteinases: Enzymes involved in breaking down proteins within the extracellular matrix as part of normal tissue remodeling. When MMP activity remains excessively elevated, as may occur in chronic wounds, it can degrade proteins and growth factors needed for healing.

Superabsorbent Polymer (SAP) Dressing: A wound dressing containing highly absorbent materials designed to take up and retain relatively large amounts of exudate. Some SAP dressings can also sequester components of wound fluid within the dressing matrix.

Sequestration: When in reference to a wound dressing, a function in which components of wound exudate are isolated or trapped away from the wound surface. Sequestration differs from absorption, which describes taking fluid into a dressing, and retention, which describes keeping that fluid within the dressing.