According to Medscape, exudate refers to the draining of liquid from open wounds in the human body. Exudate comes from the serum around inflamed, damaged tissue created by the mechanical force that created the wound or opening in the skin or mucus membrane. Mucus membrane refers to the mouth, nose or other natural openings in the body.

Serous

Serous wound drainage looks clear or straw colored. The serous material arises from protein and fluid in the tissue. At times, serous material will leak through swollen skin when a person suffers a critical illness. The serous drainage supports the healing process and contains protein, electrolytes, sugar, white cells and some microorganisms. Platelets and fibrin used in the clotting process appear in the fluid in the first 48 to 72 hours of formation of a wound to prevent bleeding. Serous wound fluid occurs as a normal process of healing.

Serosanguinous

Serosanguinous fluid appears pink due to a small number of blood cells mixing with serous drainage. "World Wide Wounds" describe a consistency of thin and watery for serosanguinous fluid. Serosanguinous fluid appears normally in the healing of wounds.

Sanguinous

Sanguinous liquid means red drainage from trauma to a blood vessel that may occur with the cleaning of a wound or excessive movement of the individual with a wound immediately after a wound emerges. The consistency appears thin and watery with sanguinous fluid. Sanguinous represents an infrequent finding in a wound.

Hemorrhaging

Hemorrhaging indicates a leaking blood vessel putting out blood. The consistency is thicker than sanguinous fluid. This situation may constitute an emergency requiring a physician's assistance to control bleeding if large amounts of blood flow from the wound site. Hemorrhaging represents an abnormal discovery in a wound.

Purulent

Purulent effluent refers to yellow, gray or green drainage that comes out of a wound when infection invades the area. The fluid contains pathogenic microorganisms along with white cells, inflammatory cells and dead or dying bacteria. The volume of the exudates increases when an infection occurs.

Cerebral Spinal Fluid

After traumatic accidents, a head or back wound may leak a clear, slightly sticky fluid from the chambers in the head or the canal around the spinal cord. Leakage of cerebral spinal fluid constitutes an emergency. The site of the leaking cerebral wound requires creating a sterile situation to allow the fluid to flow out, but not allow bacteria to enter.

Slough and Necrotic Tissue

In addition to exudates, abnormal tissue may exist in the wound, especially in chronic wounds or wounds with slow healing. Researchers Enoch and Price, writing in 2004 for the journal "World Wide Wounds," define slough as a yellow fibrinous tissue consisting of fibrin, pus and protein material. Necrotic tissue containing dead cells and debris forms in the wound from an inadequate blood supply to the area. The health care provider removes both slough and necrotic tissue in order to allow a wound to heal.