The use of the medicinal leech, Hirudo medicinalis, in the reconstructive plastic surgery
K Mumcuoglu, C Pidhorz, R Cohen, A Ofek, H Lipton
free-tissue transfer, medicinal leech, replanted digits, vascular congestion
K Mumcuoglu, C Pidhorz, R Cohen, A Ofek, H Lipton. The use of the medicinal leech, Hirudo medicinalis, in the reconstructive plastic surgery. The Internet Journal of Plastic Surgery. 2006 Volume 4 Number 2.
The medicinal leech, Hirudo medicinalis, is being used to salvage compromised microvascular free-tissue transfers, replanted digits, ears, lips and nasal tips due to venous congestion. Twenty-three patients, 8-79 years old presenting with venous congestion of revascularized or replanted fingers, free or local flaps were treated by leech therapy. Of the 15 fingers, 10 fingers were saved (4 out of 9 replanted fingers and 6 out of 6 revascularized fingers), while 17 out of 18 flaps were salvaged (3 out of 4 free flaps and all 14 island and random flaps). Fifteen patients received 1-13 units of packed blood cells (average 2.9). The patients with revascularized or replanted fingers were treated in average of 2.5 days and each finger was treated with an average of 5.7 leeches. The 15 patients with flaps were treated in average of 3.4 days and each flap was treated with an average of 9.2 leeches.
In recent years, the medicinal leech,
In July 2004, the FDA approved leeches as a medical device in the area of plastic and reconstructive surgery. A survey of all 62 plastic surgery units in the United Kingdom and the Republic of Ireland showed that the majority of these units use leeches post-operatively .
In Israel, most of the studies on leeches are about the anti-coagulant properties of the leech saliva [5, 6]. Eldor et al.  used this technique on 50 patients with congested skin flaps and in one patient with a reimplanted ear, as well as in 40 patients with post-phlebitic syndrome. In 52.5% of the patients the pain-relief was immediate and persisted for about three weeks while improved mobility was reported in 70% of them. Shenfeld  used leeches for the treatment of venous insufficiency in a replanted digit.
We report the use of leeches in 23 patients with venous congestion either after revascularized or replanted fingers or after flap reconstructions.
Patients and methods
The medicinal leech,
The area to be exposed to leeches was cleaned with sterile distilled water. Leeches were placed on the region of the removed nail for fingers or on the darker spots when dealing with flaps. The animals normally started feeding immediately, although in rare cases the skin was punctured with a sterile needle so that oozing blood would stimulate the leeches to feed.
The leech was placed on a given spot of the skin using a 5 ml syringe. For this purpose, the plunger of the syringe was removed with the help of a scissor or scalpel. The leech was placed in the barrel of the syringe and the open proximal end of the syringe was placed on the area to be treated. When the leech started feeding the syringe was removed. Feeding lasted for 45-120 minutes, and during this time the leech was monitored by one of the authors or a nurse. After auto-detachment, the leeches were killed in 70% ethyl alcohol and were disposed of in bags for biological waste.
The bite area was cleaned every 3-4 hours with a gauze sponge soaked in physiological saline to remove any locally forming clot and with a heparin (5,000 U/ml) soaked gauze, to increase the time of blood oozing. One to 5 leeches were used for each session of treatment.
Twenty-three patients (14 male and 9 female), 8-79 years (average: 35.9 years) old with devascularized or amputated fingers, open wounds after accidents or surgical wounds after scar revision were treated in Hadassah Hospital in Jerusalem during the period of May 2003 and July 2006. Table 1 shows the characteristics of injury, type of treatment and results. Accordingly, 13 fingers on 8 patients were either revascularized (6) or replanted (7) while 18 flaps were performed on 15 patients: 4 free, 7 island and 7 random.
Leech therapy was initiated after failure of more conventional treatment protocol (warming, aspirin p.o., Rheomacrodex i.v., immobilization and elevation of the injured area, use of local heparin and vasodilators) to improve venous status. In obvious cases of early venous congestion (19 cases), treatment with leeches was initiated 1-5 days post-operatively, while in 4 cases venous congestion appeared in the second week and accordingly leech therapy began 7 to 12 days post-operatively. A written informed consent was obtained from each patient (or patient's parent) before hirudotherapy was initiated.
To prevent any complication with
Of the 13 fingers belonging to 8 patients who were treated by leech therapy, 10 fingers were saved (4 out of 7 replanted fingers and 6 out of 6 revascularized fingers). Out of 18 flaps in 15 patients treated by leeches, 17 were saved (3 out of 4 free flaps and all 14 island and random flaps). 15 patients needed blood transfusion and received 67 units of packed blood cells (average: 2.9/patient). The 8 patients with 13 revascularized or replanted fingers were treated in average of 3.2 days and each finger was treated with an average of 5.5 leeches. The 15 patients with 18 flaps were treated in average of 5.1 days and each flap was treated with an average of 13.3 leeches.Treatment was continued until angiogenesis was sufficient to restore effective venous drainage, which was subjectively appreciated by the improved color of the skin (Table 1).
Case Report 1
A 44-year old male patient was admitted to the emergency room with an avulsion of the pulps of the 4 fingers of his dominant hand (Fig. 1). The exposed distal phalanxes were covered with 4 digital island flaps (2 reversed and 2 direct) (Fig. 2 and 3). Venous congestion was seen one day post-operatively and leech therapy was initiated. Leeches were applied once daily for 3 days until the venous congestion was improved. Two months post-operatively the patient regained full function of his fingers/hand (Fig. 4) including a normal handwriting, allowing him to go back to his work as a schoolteacher.
Case Report 2
An eight year old girl was admitted to the Emergency room with amputation of the pulp of the right dominant thumb, after a door was closed on her thumb 2 hours earlier(Fig. 5). The pulp was sutured back to the right thumb in the ER as a composite flap, but underwent gradual necrosis during the next 10 days with exposure of most of its distal phalanx.
To avoid skeletal shortening, a thumb reconstruction was performed, using a free flap taken from the lateral hemipulp of the ipsilateral big toe (Figs. 6 and 7). The free hemipulp flap was congested on post-operative day two, and it was treated with 1 leech daily for post-operative days two, three and four (Fig. 8). Under this treatment regimen, the flap congestion resolved, and the patient was discharged with a viable flap on post-operative day eleven. At 6 months, the function and sensory function of the thumb was normal (Fig. 9) allowing a normal handwriting.
Leeches are generally used during the critical post-operative period when venous outflow cannot match the arterial inflow. This happens most commonly with replanted and revascularized digits as well as with vascularly compromised local and free flaps. Blood clot formation within the venous outflow could 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. Accordingly, leech therapy is used until angiogenesis gradually improves the physiological venous drainage .
During feeding, leeches ingest approximately 5 ml of blood. Due to the anticoagulant- and vasodilator-containing saliva, the wound oozes up to 50 ml of blood within 24-48 hrs. The leach saliva contains coagulation inhibitors (hirudin, factor Xa inhibitor and bdellin), a platelet aggregation inhibitor (apyrase), a vasodilator (histamine) and collagenase and hyaluronidase, which facilitate local infiltration of the antithrombotic mediators into the congested tissue. Thus, leech therapy addresses both the venous outflow and microcirculation [5, 6, 10].
Successful salvage of tissue with leeches occurs in 70-80% of cases . In the present study, 44.4% of the replanted fingers, all revascularized fingers and 94.4% of all flaps was salvaged by leech therapy. Four out of 5 fingers that were lost were pre-operatively mismanaged before arrival at our institution (direct contact with ice or plain water), while the fifth finger was severely injured by a grinder. The only flap failure (free flap) could be explained by its placement in an irradiated area, which prevented the angiogenesis.
Leech therapy is used daily until venous capillary return is established across the wound border by angiogenesis. In the present study, the treatment with leeches lasted on average of 2.5 days for fingers and 3.5 days for the flaps. In other clinical studies, the treatment lasted for 4-6 days [11,12,13,14]. In fact, the decision regarding the duration of the leech treatment is entirely empiric based on subjective appreciation of the color of the skin, capillary refill, and the color of bleeding to pinprick.
No significant adverse reactions were observed in any of the patients treated with leeches in this study. A few patients reacted with revulsion when they first heard about this treatment modality; however, none of the patients refused the treatment with leeches.
No side effects due to leach therapy were observed. The antibiotic prophylaxis with 500 mg of ciprofloxacin for Aeromonas infections appears appropriate. Symbiotic bacteria (Aeromonas sp.) living in the intestinal tract of the leech may cause infections in 4-20% of the patients and therefore a prophylactic treatment with antibiotics is justified. In case of Aeromonas infections, the rate of salvage drops to 30% or less [15,16,17]. Aeromonas species are sensitive to second- and third-generation cephalosporins, ciprofloxacin, sulfamethoxazone-trimethoprim, tetracycline and aminoglycosides .
In the post-operative period, all our patients received treatment to reduce blood viscosity and coagulation. The decongestive benefit to the flap or digit comes not only from the initial amount of blood extracted (approximately 5 ml), but from the 50 ml of additional blood loss that typically occurs as a slow ooze over the next 24-48 hrs .
The excess bleeding can be of concern and transfusions may be needed. In the present study, 15 out of 23 patients needed blood transfusion and received 67 units of packed blood cells (average: 2.9). Four to 6 units of packet blood cells were used in reports by other authors [3, 14]. Therefore, special care should be taken in patients with a tendency to hemorrhage, severe anemia or for those taking anticoagulants or platelet-inhibitor drugs .
In conclusion, leech therapy should be considered as an integral part of the armamentarium used in reconstructive surgery. It improves greatly the success rate of the surgery in cases of post-operative venous congestions, allowing blood drainage until angiogenesis is established.
Dr. Kosta Y. Mumcuoglu, Department of Parasitology, Hebrew University-Hadassah Medical School, P.O.Box 12272, Jerusalem 91120, Israel Tel.: ++972 2 675-8093, Fax: ++972 2 675-7425, E-mail: email@example.com