Optimizing Leech Therapy for Venous Congestion in Replantation: A Systematic Review and Meta-Analysis of Timing, Duration, and Clinical Outcomes

Medicinal leech therapy, utilizing Hirudo medicinalis, has emerged as a valuable adjunctive treatment for managing venous congestion in microsurgery. Leeches alleviate congestion by actively extracting blood and secreting hirudin, a potent anticoagulant, along with other bioactive substances that promote local vasodilation and temporary drainage . This facilitates tissue survival until neovascularization establishes sufficient venous outflow, typically within 5–7 days post-replantation . The use of leeches in medicine dates back thousands of years, with historical records from ancient Egypt (circa 1500 BCE) describing their application for bloodletting in various ailments [5]. In the 19th century, leech therapy peaked in Europe, with millions of leeches used annually for conditions ranging from inflammation to fever [6]. The advent of modern medicine reduced their use, but the 1980s marked a resurgence in microsurgery, particularly after reports demonstrated their efficacy in salvaging congested flaps and replants . Today, leech therapy is a recognized intervention in plastic and reconstructive surgery, yet its application remains guided by anecdotal experience and small-scale studies rather than standardized protocols.