Learn How to Determine What Wound Exudate Is Telling You

Published on July 1, 2020 by Bill Richlen, PT, WCC, DWC




  • How do we correct that? 


Wound Exudate Basics

Let’s begin with reviewing the five types of wound exudate:

  • Serous generally presents as thin, clear or amber in color, and is often considered normal in a wound.
  • Sanguineous presents as bleeding secondary to tissue damage within the wound. 
  • Serosanguineous is thin, watery, pink to pale pink in color as a result of red blood cells mixed with plasma due to minor capillary damage.
  • Seropurulent is thin, watery, cloudy yellow to tan in color.
  • Purulent is thick, viscous, tan, brown or green in color.

We also need to assess the amount of wound exudate, which requires observing the condition of the wound and the dressing.

  • None (no drainage) indicates that the dressing and wound bed are dry.
  • Scant indicates nothing measurable on the dressing, but the wound bed is moist.
  • Small/minimal indicates less than 25% of the dressing is involved and the wound bed is very moist.
  • Moderate indicates 25%-75% of the dressing is involved and the wound bed is wet.
  • Large/copious indicates greater than 75% of the dressing is involved and the wound is filled with fluid.

These are the basics to our assessment and documentation, however we need to ask the critical questions.

What the Exudate is Telling Us

In looking at the type, color and amount presenting in the wound, we need to determine what the wound exudate is telling us.

If we note sanguineous drainage, for example, it indicates some level of damage to capillaries in the tissue. That begs the question “what is causing the damage?”

The subsequent amount of sanguineous drainage would indicate how significant the damage was. 

Once we have determined the cause, we implement a treatment approach that reduces or eliminates tissue damage altogether.

Another example would be a wound with large amounts of serous drainage.

Moderate-to-large amounts of exudate is never normal.

Therefore, our first objective is to determine what is causing these high levels of exudate. If it is truly serous exudate, there would be a number of possibilities, such as localized staphylococcus infection, chronic inflammation due to biofilm or high levels of MMPs to name a few.

However, one might more closely inspect the “serous” exudate and notice it smells like urine indicating a urinary fistula. Or they might have significant underlying venous and/or lymphatic disease, which is creating the conditions for excessive serous drainage. 

We also can consider the color and viscosity of the wound exudate.

Thick, milky white to tan could be associated with autolytic debridement and the liquefaction of the necrotic tissue or lymphatic exudate. Whereas thick, yellow to green may indicate a high bioburden in the wound. 

We could elaborate on different scenarios that we may face, but the main priority is to critically analyze what is going on in the wound. This is important so you can provide care that removes the abnormal conditions and manages the normal conditions to support successful wound healing.

Until next time, heal on!

To learn more about caring for wounds, check out our Live Online Skin and Wound Management Course!

Bill Richlen, PT, WCC, DWC
Bill Richlen, PT, WCC, DWC


