There are many different types of wound drainage, such as purulent – a sign of infection.

Different types of wounds require different types of wound care products. One of the key factors that must be taken into consideration is the amount of exudate – pus, blood and other fluids – coming from the affected area. For example, alginates are typically used for ulcers with heavy exudate, while transparent films are best geared toward wounds with little or no drainage. So it’s important to know the various categories of wound drainage so you can discuss the proper wound healing plan with your clinician. Review these basic types of drainage:


This type of drainage is plasma that’s thin, clear and watery. It’s normal to experience a small amount of this type of exudate during the inflammatory wound healing stages. However, excessive serous drainage may be a sign that you have high bioburden, which is the number of unsterilized bacteria living on the surface of the wound.


Sanguineous drainage is fresh blood that is prevalent among deep wounds of full and partial thickness. During the inflammatory stage, a small amount of this bloody leakage is natural. But when this type of exudate occurs during other wound healing stages, it may be an indicator that the wound bed has undergone trauma, such as during dressing changes, which can hinder healing.


Among the most common of all drainage types is serosanguineous. This leakage is thin and watery, and it’s pink in color (it can also be a darker red). The pink tinge is the effect of red blood cells in the fluid, which is a sign that there is damage to the capillaries. Such damage generally occurs during wound dressing changes and can disrupt the healing process.


You may be experiencing purulent drainage when the leakage from your wound appears milky. It’s generally gray, green or yellow, and purulent drainage is most commonly thick in consistency, though some purulent exudate can be thin. This may be a sign that the wound has an infection – the fluid becomes off-color and thick because pathogenic microorganisms and dying bacteria in addition to inflammatory and white cells are invading the affected area, according to Clinical Microbiology Reviews. As the infection worsens, the amount of purulent leakage increases. Be sure to keep an eye out for this type of exudate and see a clinician if it occurs.

Advanced Tissue is the nation’s leader in delivering specialized wound care supplies to patients, delivering to both homes and long-term care facilities.