What Is the Yellow Stuff in a Wound Bed? Slough vs. Normal Drainage Explained
What is the yellow stuff in the wound bed?
The Quick Answer
The yellow substance is typically **slough**—a viscous, fibrinous necrotic tissue ranging from pale yellow to tan that adheres loosely or firmly to the wound bed. Unlike clear serous drainage (a normal healing fluid), slough represents devitalized tissue that impedes healing and requires professional debridement to restore the wound's progression.
Why We Ask This
Caregivers and patients struggle to differentiate between harmless yellow-tinged fluid and pathological slough, leading to either dangerous neglect of necrotic tissue or unnecessary alarm about normal serous exudate.
The Practical Science
Slough appears when macrophages fail to clear cellular debris during inflammation, creating a protein-rich matrix that traps bacteria. Its yellow hue comes from degraded hemoglobin and leukocyte remnants, distinct from the translucent quality of serous drainage.
In Clinical Practice
In clinical practice, a wound with yellow slough would be documented as '50% slough coverage' during assessment, triggering selection of enzymatic debriding agents like collagenase rather than standard absorptive dressings used for clean wounds.
References & Context
Slough: what does it mean and how can it be managed"The appearance of slough is typically a pale yellow, viscous fibrinous tissue and can range from yellow to tan, usually, but not always, covering the entire wound bed. It can appear on parts of the wound bed and tends to be either loosely adhered to the surface of the wound or firmly attached1,7–9."