They produce this to prevent their host from forming a clot so that they can feast on blood more easily. Leeches produce an enzyme in their saliva called hirudin.
In rare situations, this is not possible or not indicated, and in these situations leeches may be used to alleviate the venous congestion. Venous congestion in the majority of cases is best managed by returning the patient rapidly to the OR to remove the venous obstruction. This accumulated blood eventually can destroy the integrity of the tissue and the tissue can die. Blood then accumulates in the tissue as it cannot get out. Venous congestion occurs when the veins that drain blood from a tissue are unable to do their job because of clotted blood within them or from external pressure on the draining vein.
Return to: Microvascular Surgery Protocols see Free Flap Monitoring and Salvage Medicinal Leech Therapy on Head and Neck Patients
