Leeching as Salvage Venous Drainage in Ear Reconstruction: Clinical Case and Review of Literature

Abstract

Background:

Ear avulsion is a rare complication of different traumas, such as car accidents, human or animal bites and stab wounds, and can result in dramatic cosmetic consequences for the patient. Ear replantation, revascularization, and reattachment are the options offering best aesthetic results. But venous outflow insufficiency is responsible for a high rate of failures. Leeching is one the most efficient methods to relieve venous congestion. It has been used as an alternative venous outflow in case of severe impairment of the physiologic one.

Methods:

We present a case of successful rescue of a congested reattached ear by leeching after subtotal avulsion, along with a review of the literature on cases of avulsed auricle reconstruction salvaged by hirudotherapy. Data were collected and analyzed to identify a best regimen to deal with venous congestion.

Results:

More than 130 cases of avulsed auricle savage are described in the literature, in a fourth of which leech therapy was used in the management of venous congestion.

Discussion:

In case of both venous outflow deficit or absence, leeches are a potentially successful option to correct the congestion while new veins reestablish normal physiology. The need for anticoagulant/antiaggregant therapy, antibiotics, and often blood transfusion are the main pitfalls of leeching.

Conclusion:

Leeches can be considered a salvage method for ear replantation and reattachment in those cases that lack venous outflow in the presence of valid arterial inflow.

INTRODUCTION

Ear avulsion is a rare dramatic event that can lead to severe deformity after different types of trauma such as car accidents, bites, and stab wounds. Reattachment of the avulsed ear offers the best aesthetic results.^1–3 In the absence of adequate perfusion or suitable vessels for microsurgical replantation/revascularization, alternative procedures can be used to attempt ear salvage such as composite grafting, the pocket-principle technique, or local flaps.^4–6

Venous congestion due to thrombosis or insufficient venous connection is the most common complication responsible for the failure of ear revascularization and reattachment. In the presence of adequate arterial inflow, the presence of sufficient venous drainage should be assessed to prevent blood stasis and delayed necrosis. The avulsion mechanism of ear trauma often determines traction injuries to small ear vessels reducing the chances of identifying functioning veins or veins suitable for repair. Nonetheless, ear salvage should be attempted also in the lack of venous repair, as recently reported by Momeni et al.^7–14

External venous decompression is a well-established approach to venous congestion. In ear salvage, it is advocated as alternative drainage until venous connections with the recipient bed develop.^15,16 Tissue milking, pin pricking, use of medicinal leeches, pharmacological leeching are common methods to drain the congested venous system of replanted tissues, often associated with systemic anticoagulant therapy.^17–19 Among those, leeching is one of the most commonly employed in congested ears salvage, and several successful cases are reported in the literature, but a clear consensus on the protocol of application to ear salvage is still lacking.

CASE REPORT

A 26-year-old man was involved in a car accident resulting in almost complete avulsion of the left ear associated with a wide laceration of the left tempo-parietal scalp (Fig. 1). He reached the operating theatre in 5 hours from the time of injury, where the ear was examined and recognized to have an effective arterial inflow (seen with microsurgical loupes and confirmed by a positive pin pricking test) provided through a small skin bridge. Refill was brisk, and an attempt to find suitable veins for anastomosis to increase blood outflow had no success. The ear was sutured to the scalp with 4-0 and 2-0 nylon sutures. No drains were positioned to maximize skin-to-skin contact.

Fig. 1.

Avulsion of the left ear.

Venous congestion was managed by starting leeching immediately after surgery (Fig. 2). Leeches were applied continuously for the first 4 postoperative days and changed every 4 hours, then the ear was monitored every 6 hours for 7 days, and leeches were reapplied in the presence of signs of venous congestion, with up to 3 leeches per day.

Fig. 2.

Intraoperatively the auricle developed venous congestion and leeching was started immediately after the surgery.

The patient was given ceftriaxone 1 g twice daily, 4,000 units of enoxaparin sodium s.c. and 325 mg of Aspirin oral per day for 2 weeks. Bloods were monitored, and 2 units of red blood cells were transfused. The patient was discharged to outpatient care 2 weeks after surgery (Fig. 3). At 3 years follow-up, the auricle maintained a satisfactory shape.

Fig. 3.

Complete healing 3 years after the trauma.

MATERIALS AND METHODS

The literature in the Medline database (Pubmed) was searched using combinations of key words (“ear replantation,” “ear avulsion,” “hirudotherapy,” “hirudo medicinalis,” “leech,” “medicinal leech”).

Studies published in English describing ear salvage with leech therapy in total and subtotal amputations (> 80% of the surface of the auricle) were selected. Articles including only descriptive reports, historical articles, correspondence, editorials, and reviews were excluded.

Residual/reestablished perfusion, regiment of leech application, anticoagulant and antiaggregant therapy, blood transfusions, and antibiotics administered in successful cases and complications were analyzed.

RESULTS

We identified 131 cases of successful ear salvage reported in the literature from 1970 to 2016. Twelve cases were excluded for unclear description of leeches use. Leeches were employed in 40 cases of 119.

In 4 of these cases, perfusion was conserved through an intact skin pedicle; it was reestablished by arterial microsurgical anastomosis in 22 cases and by an artero-venous anastomosis in 2 cases. As for venous drainage, it appeared to be intact in 3 cases and was repaired intraoperatively in 9 cases, with 2 venous anastomoses performed in 1 case. Sixteen amputated auricles lacked adequate veins.

Leeches were applied immediately after surgery in 12 cases of 16 with absent venous outflow and in 2 cases of 3 with intact skin pedicle and adequate arterial perfusion. Only 2 cases of 8 with 1 or 2 venous anastomoses required early leeching. The leeching regimen was changed from regularly intermittent to tapered on venous congestion 2–5 days after surgery (mean of 3.8 days) in 20 cases. Only in 2 cases the authors preferred to taper leeches application on venous congestion from the beginning. In 7 cases, the application regimen was not reported.

The number of leeches used by different authors was highly variable, ranging from 1 leech per day to as many as 1 every hour. The time interval between applications was differed similarly.

The duration of leech therapy ranged from 3 to 17 days (mean, 8.5 days). In cases with absent venous drainage, the application of leeches was continuous for a mean of 5.2 days, and then tapered basing on signs of vascular congestion.

In addition to leech therapy, the majority of patients received either a regimen of double anticoagulation or an association of anticoagulant and antiaggregant. Two patients received dextran and oral aspirin, 7 patients received heparin and oral aspirin, 5 patients received dextran, heparin, and oral aspirin. Ten patients received a monotherapy of dextran, heparin, or warfarin. In 2 cases, the type of anticoagulant is not reported, and in 1 case, no anticoagulant therapy was administered. Adjunctive therapy was equally highly variable and included intraoperative boluses of heparin, verapamil, postoperative oral buflomedil or prostaglandin, warming blanket, and warm room.

Twenty cases of 29 patients required blood transfusions (with a mean of 5.37 packed red blood cells units per patient). Twenty-five patients received antibiotic prophylaxis, which was specified in 14 reports; no infective complications are described (Table 1).

Table 1.

Leech Therapy Regimens in Successful Cases of Ear Salvage

DISCUSSION

The auricle has no functional relevance, but it is a major element in defining face appearance, and its loss often has a significant psychological impact on the individual. Any attempt should be made to achieve the best possible preservation of its shape in case of partial or total ear avulsions. Either with a conserved or reestablished perfusion, insufficient venous drainage is the main factor leading to failure. Some authors believe that a vein to vein repair, or sometimes an artery to vein fistula, is mandatory for the replantation/revascularization of the auricle and that only an efficient physiologic drainage guarantees success.^5,7,20,21 On the contrary, many cases are reported of successful ear replantation despite absent venous drainage.^16,22–27 Momeni et al.¹¹ recently confirmed the role of alternative venous decongestion methods in ear salvage, reaffirming once again the importance of attempting ear salvage even with artery only anastomosis.²⁸

Flushing or soaking with heparin sodium solution, subcutaneous heparin injection, daily punctures, and multiple stab wounds are classic techniques employed in reconstructive microsurgery, but they are anecdotal in ear reconstruction.

Medicinal leeching is described by many authors for secondary auricle salvage in cases of vein thrombosis after anastomosis.^{10,17,23,29–31} But it is also proposed as a primary alternative when microsurgical anastomosis is not feasible.^{8,15,22,32–37}

The saliva of leeches contains vasodilators (histamine-like products), inhibitors of platelet aggregation (calian, apyrase, saratin), anticoagulants (hirudin), permeability factors (hyaluronidase) and proteinase inhibitors (bdellin, egline). Together with the active ingestion of blood by the leech, each bite increases and prolongs bleeding after detachment.^10,38,39

Anticoagulant and antiaggregant agents can be administered systemically in addition to leeches to maintain blood flow and prevent thrombosis. This was the case in the majority of reports analyzed, suggesting the administration of at least a combination of low molecular weight heparin and 325 mg of aspirin daily. Dextran or other agents were also introduced by some authors (Table 1).

Peripheral artery disease, severe immunocompromised status, and history of allergic reactions to leeches are absolute contraindications.⁴⁰ A chronic anticoagulant therapy represents a relative contraindication.³⁵ In any case, the general conditions of the patient must be taken into account, because leeching implies blood loss, which in some patients is better avoided.³²

Leech-borne infections have an incidence between 2.4% and 36.2%, and along with exsanguination is the main complication of leech therapy. This should be discussed with the patient before starting application as part of consenting.

Aeromonas spp., Pseudomonas spp. and Vibrio spp. can cause localized cellulitis, meningitis, and septic shock, occurring from 24 hours to 26 days after leeching. In addition, leeches are potential vectors of blood-borne diseases, including HIV and hepatitis viruses. Proper management of the leeches to avoid cross-contamination between patients is mandatory.

Aeromonas hydrophilia, a facultative Gram-negative rod that colonizes leech gut, is the major cause of infectious complications after leeching. It contributes to blood digestion and decontaminated leeches are less effective. Infection can be prevented by antibiotic prophylaxis with ciprofloxacin 250 mg twice daily as first-line therapy; alternatively, trimethoprim/sulfamethoxazole or a third-generation cephalosporin should be considered.^41–43

Blood loss is an intrinsic consequence of the use of leech therapy. Hematocrit and blood count should be monitored closely, and RBC transfusions should be promptly administered.^{6,14,35,44,45}

Scarring at leech biting sites is sometimes described. No significant scars were noticeable in the case we treated at 3 years follow-up, neither it was reported in other cases.

Intensive nursing and medical assistance and often a prolonged hospital stay are commonly necessary in patients treated with leech therapy. It is a time and staff-consuming therapy.¹⁰

A clear consensus on the application regimen has not been reached yet. A difficulty in defining a universal protocol for leech application is that each patient and tissue flap will require and respond differently based on the anatomy, severity of injury, mass of tissue, arterial inflow, metabolic activity, speed of neovascularization with development of new venous connections.³⁷ Basing on the literature, we believe it could be useful to consider 2 different scenarios in leech therapy regimens for salvaged ears. In cases of present postoperative venous drainage, leeches should be applied at need to relieve the venous congestion that may eventually arise if the venous drainage is insufficient when blood pressure rises or tissues swell up. In cases of absent venous outflow, an immediate and continuous application of leeches can replace the absent venous drainage of the amputated auricle. In this scenario (Table 1), leeches should be intensively applied over the first days while allowing new venous connections to develop. After a mean of 5 days, the application regimen can be tapered based on signs of venous congestion, thus reducing the burden to the patient and staff and limiting blood loss (Fig. 4).

Fig. 4.

Comparison of different conditions of venous congestion.

Main limits to defining the role of leech therapy in avulsed ears salvage are the low number and at the same time variety of cases reported, along with the lack of reports on unsuccessful cases or of control cases in which alternative methods to relieve venous congestion are compared with hirudotherapy.

CONCLUSIONS

Leeching has the potential to move favorably the balance in attempts to salvage avulsed ears and should be a tool available and considered when such cases present.