H. LEECHES IN PLASTIC SURGERY
USE OF LEECHES IN PLASTIC SURGERY
Medicinal leeches have been used since 1960’s for the salvage of tissue with venous congestion. Deganc and Zdravic [51] conducted the first treatment of congested flaps using leeches. Today, especially in the field of reconstructive microsurgery, medicinal leech therapy is enjoying a renaissance [3,16,17,52]. In 2004, the FDA approved leeches as a medical device in the field of plastic and reconstructive surgery.
Hirudotherapy is usually initiated after failure of more conventional treatment modalities (warming, aspirin p. o., immobilization and elevation of the injured area, use of local heparin and vasodilators) to improve venous status.
Leeches are generally used during the critical postoperative period when venous outflow cannot match the arterial inflow, which can lead to venous congestion, clinically identified by the dusky purple appearance of the skin. If this complication is not corrected, cell death may result and the flap or finger may be lost. Therefore, medicinal leeches are used to salvage compromised microvascular free-tissue transfers, replanted digits, ears, lips, and nasal tips until angiogenesis gradually improves the physiological venous drainage. Frodel et al. [19] used medicinal leeches to salvage soft tissue avulsion in key facial structures of 4 patients involving avulsions of the ear, nose, lip, and scalp. In addition to using leech therapy in head and neck reconstruction, there are numerous studies showing the use of leech therapy for hematomas, penile and total scalp replantation, and pedicled skin flaps, as well as for the salvage of the entire lower limp [3,20-32]. Leech therapy is usually initiated after failure of more conventional treatment modalities such as warming, aspirin, rheomacrodex (i.v.), immobilization and elevation of the injured area, and use of local heparin and vasodilators to improve venous status. Venous obstruction causes micro-circulatory thrombosis, platelet trapping, and stasis. Thus, even after successful reanastomosis, secondary changes in the microcirculation can persist and prevent adequate outflow from being reestablished. Free flaps, pedicled flaps, and replanted tissues can survive arterial insufficiency for up to 13 hours, but venous congestion can cause necrosis within three hours. Medicinal leeches may be helpful in treating tissues with venous insufficiency by establishing temporary venous outflow, until graft neovascularization takes place [33]. In July 2004, the FDA approved leeches as a medical device in the field of plastic and reconstructive surgery.
The persistent bleeding largely potentiates tissue decongestion and leads to loss of blood, relief of capillary net, decrease in venous congestion, decompression of the nerve trunks and endings, increase in lymph flow, positive changes of local hemodynamics, amelioration of hemorheology, increase of oxygen supply, improvement of tissue metabolism, and elimination of tissue ischemia [16].
Before the beginning of the treatment the patient should be informed about the benefits and potential risks of the treatment. For hirudotherapists who are not physicians, the whiten consent of the responsible physician and this of the patient should be taken. The patient should receive prophylactic treatment with antibiotics, the leeches should thoroughly be rinsed with deionized water, and the area on which leeches will be applied should be cleaning from existing gels. A thick layer of gauze can be applied around the leech(es) to prevent detached leeches from attaching themselves to other parts of the skin or even under the flap, to fall inside the dressing around the wound or other parts of the patient’s body.
A survey of all 62 plastic surgery units in the United Kingdom and the Republic of Ireland showed that the majority of these units uses leeches postoperatively [34].