The Use of Medicinal Leeches in Fingertip Replantation without Venous Anastomosis – Case Report of a 4-year-old Patient

Introduction

Replantation of amputated fingertip is a technical challenge to the microsurgeons. The success rate depends directly on the level of the amputation, and on the availability and on the size of preserved vessels. Classification of fingertip amputations based on the level of the amputation is shown in Table 1 (1,2). Unfortunately, in distal digital amputations, veins are usually not easily found in the right position or they are even absent and thus great number of salvage attempts fail because of venous congestion (2,3). The inability to perform a venous anastomosis is believed by some to be a contraindication to replantation (4).

Repair of volar vein (5,6) and arteriovenous shunting (6–10) are the surgical techniques of venous drainage restoration but their use is limited to the presence of the appropriate vessels. For the cases when venous system cannot be restored, several techniques have been developed to provide temporary drainage by using controlled bleeding while new venous ingrowth occurs. It takes normally 5–6 days, thus there may be a need for blood transfusion. One of the earliest techniques of controlled bleeding was to make an incision in the fingertip and allow it to bleed (3,11). This protocol may be enhanced by subcutaneous injections of heparin around the incision (3). Another option is partial ablation of the nail when drainage is obtained from the nail bed (12). The use of medicinal leeches is another alternative of controlled bleeding from a replanted fingertip (4,13,14,15).

A case report of a 4-year-old patient after fingertip replantation without venous anastomosis when temporary venous drainage was provided by the medicinal leeches is reported together with literature review.

Case report

A 4-year-old male patient was transferred to our department after he suffered from guillotine amputation in his right second distal phalanx (on the borderline of zone I and II according Tamai’s classification) at home from a meat grinder (Fig. 1). Cold ischemia time was 8 hours at the beginning of the surgery. Osteosynthesis was performed using one axial 23 gauge needle and the fingertip was salvaged by repairing ulnar digital artery using 11-0 monofilament nylon suture. The patient received intravenous bolus of heparin (500 IU). Venous anastomosis was not feasible due to extremely small size of present vessels. Revascularisation was delayed. The digit achieved healthy colour in 15 minutes.

Postoperative care

Postoperatively, the patient was monitored at intensive care unit and he was receiving intravenous antibiotics and continuous heparin (2750 IU/d) infusion to prevent occlusion of arterial anastomosis. The perfusion of the replanted fingertip was closely monitored by observation of appearance, skin turgor, colour, temperature and bleeding.

The first signs of venous congestion were observed 3 hours postoperatively (Fig. 2), the first medicinal leech (Hirudo medicinalis) was applied 6 hours postoperatively protecting carefully all the other fingers (Fig. 3). The time of attachment varied from 15 to 30 minutes. When the leech was full, it dropped off the digit spontaneously. It was subsequently destroyed by immersion in ethanol. The Y-shaped incision and skin suture continued to bleed for 4 to 8 hours after the leech dropped off. Leeches were applied in 12-hour interval during first 48 postoperative hours. Termination of this treatment was determined by clinical examination. The return of normal capillary refill times was considered to be a sign of new venous drainage development (Fig. 4). All medicinal leeches were obtained from a commercial distributor (Arcus Brno, Czech Republic). Leeches were stored at 10°C up to 6 months prior to use.

The patient was receiving continuous intravenous heparin infusion (2750 IU/d) for 5 days. Patient’s haemoglobin level was closely monitored. As the lowest haemoglobin level was 98 g/L and as no signs of hypovolemia were observed, there was no need of blood transfusion.

Clinical follow-up

The immobilisation and osteosynthesis were left for 4 weeks postoperatively, when rehabilitation of the hand was initiated. Two mouths postoperatively, virtually full active range of motion of the replanted finger was observed with no significant differences in two-point discrimination comparing with the right 3^rd finger (Fig. 5).

Discussion

The use of medicinal leeches has been recommended by the physicians since the earliest days of medicine. Batchelor et. al. used leeches in a series of seven facial congested pedicle flaps and French microsurgeons begun to use leeches after digital replantation for their venous congestion – Foucher et al. published the results of distal digital replantation in 14 patients with no venous anastomosis repaired who were treated with medicinal leeches (4,15,16).

The effect of leech therapy on venous congestion is immediate and delayed. During leech attachment to the patient, it bites the patient’s skin and it removes approximately 5–10 cc of blood and venous congestion is reduced immediately. At the same time, during its attachment, it injects the salivary gland fluid into the fingertip. Saliva of Hirudo medicinalis contains an enzyme known as hirudin. Hirudin was discovered by Haycraft in 1883 as the first known anticoagulant (17). This polypeptide of 65 amino acids is a potent inhibitor of the conversion of prothrombin to thrombin. Thus, also conversion of fibrinogen to fibrin is blocked indirectly (18). After the leech drops off the finger, hirudin acts locally to maintain a steady bleeding wound for approximately 4–8 hours. This controlled bleeding keeps a digit from becoming congested that is considered to be delayed effect of leech therapy on venous congestion of the digit. Local anticoagulant effect of hirudin may reduce need of systemic heparinization.

The Y-shaped incision made by the jaws of the leech is relatively superficial as a leech is probably able to find superficial vessel. The extent of blood loss is sufficient to keep a digit decongested. Comparing with nail avulsion, incision of the pulp or “chemical leech” therapy (superficial skin incision at the fingertip with topical subcutaneous injection of heparin around the incision), bleeding seems to be slow and blood transfusion is avoided (1,2). Infection is the most common complication of leeching. The main infection-causing agent is the gram-positive Aeromonas hydrophila that is resistant to penicillins and to the first generation of cephalosporins. Targeted antibiotic treatment for infection should contain aminoglycosides or fluoroquinolones (19).

Development of new vascular bed providing venous drainage takes normally 5–6 days. If there is no vein ensuring venous outflow, any controlled bleeding technique is often recommended for this period. In our case report of a 4-year-old patient, the amputated fingertip got pink colour in 48 hours with positive capillary refill test and it was stabilised afterwards. Such uncommonly short period of blood circulation restore may be explained by osseous venous drainage or by accelerated neovascularisation in early childhood.

We believed that replantation based on one arterial anastomosis without any venous anastomosis with the use of medicinal leeches postoperatively may increase success rate of fingertip replantation in zone I according to Tamai’s classification (in zone II and III according Allan’s classification) comparing with composite graft technique. Clinical study in greater number of patients is needed to confirm this hypothesis.

Conclusion

This early experience with leeching in the treatment of venous congestion in replanted fingertip without any venous anastomosis is very promising. In our case report of a 4-year-old patient, very short period of the leech application was described with no need of blood transfusion. Leeching as an ancient method of treatment should be considered as a proper and finger-saving therapeutic alternative for venous decongestion in modern replantation surgery due to ease of leech application and reduced number of side-effects.

Address for correspondence:

Libor Streit, M.D.

Department of Plastic and Aesthetic Surgery

St. Anne’s University Hospital

Berkova 34

612 00, Brno

Czech Republic

E-mail: streit@fnusa.cz