Femoral vein transposition fistula with short skip incisions: an optimised minimally invasive technique

Introduction

Autologous arteriovenous fistula (AVF) is the preferred vascular access route for patients with chronic kidney disease (CKD) requiring haemodialysis. While upper extremities are the preferred site for vascular access, complications can lead to upper vein exhaustion over time. Lower-limb vascular alternatives include great saphenous vein transposition or femoral-femoral prosthetic loop graft. However, these approaches are associated with high complications and low patency rates.^1,2 Femoral vein (tFV) transposition fistula using a long, single incision in the thigh was introduced as an alternative by Huber et al. (one patient) and Jackson (two patients) in 2000.^3,4 This technique improves patency rates with lower infection than grafts or great saphenous vein transposition. Still, wound complications such as infection or haematoma remain a problem due to the lengthy single incision required for femoral vein harvesting.^5,6 This article aims to describe tFV with three short skip incisions in the thigh using an optimised minimally invasive approach. We use linear superficial tunnelling of the vein, allowing a more straightforward identification and lengthier area to puncture the vein.

Technical details

After exhaustion of upper-limb vascular accesses, three patients were selected to undergo tFV. Pre-operative vascular ultrasound played a pivotal role in delineating the anatomical course of the femoral vein (FV), its patency and relationship with the superficial femoral artery, and pinpointing key landmarks such as the confluence of the common femoral vein and major venous tributaries to the FV. Significant peripheral arterial disease, obesity, diabetes and superficial vein insufficiency were considered contraindications for this technique.

The procedure is performed as follows: [1] A 5-cm skin incision is made below the inguinal crease, directly over the common femoral vein confluence. This allows an elastic loop to be wrapped around to identify the deep femoral vein. Adequate mobilisation of the sartorius muscle ensures optimal FV harvest in this region. [2] A second 5-cm incision is made in the mid-thigh region, and the FV is again identified. Venous tributaries are ligated between these two incisions, and the vein is mobilised using standard venous harvesting techniques. [3] A third similar incision is made in the distal thigh, proximal to the adductor canal. The vein is harvested further until this segment, above the sartorius muscle. The adductor magnus tendon is divided when a more extended vein size is needed. Figure 1 illustrates the three incisions made along the medial aspect of the thigh. [4] The FV is divided distally and transposed laterally to the superficial femoral artery, posteriorly and medially to the vein. Before tunnelization, the vein is dilated using saline and reviewed for ligation of additional tributaries (Figure 2). [5] Subcutaneous tunnelization is executed using the Matos Tunneler without requiring intermediate skin incisions (Figure 3). ⁷ Lateral tunnelization through the anterior aspect of the thigh avoids the scarring tissue and ensures a zone for puncture with suitable length. [6] The vein is anastomosed to the distal superficial femoral artery using standard techniques in a latero-terminal configuration between the adductor tendon and the sartorius muscle. Arteriotomy should be no larger than 3–4 mm to avoid lower-limb steal syndrome. An immediate assessment of the fistula is conducted using palpation and Doppler flow. Incisions are closed in layers with drains, if deemed necessary by the surgical team (Figure 4). The procedures lasted, on average, 120 min. Recovery was uneventful, and patients were discharged home on average 6 days after the procedure. Wound healing was satisfactory; the fistula was punctured on average 3 weeks after the procedure, demonstrating the successful and practical application of the new technique in these three patients.OPEN IN VIEWER

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Figure 2.

Transposed femoral vein before tunnelization. Note the superficial femoral artery is identified in the distal part of the thigh.

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Figure 3.

Superficial transposition of the femoral vein through the anterior aspect of the thigh, using the Matos Tunneler device.

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Figure 4.

Skin incisions closure with the path of transposed femoral vein visible, highlighting the minimal invasiveness of this procedure.

Discussion

Many authors still consider loop grafts the primary choice for patients needing lower-limb vascular access. However, grafts often face complications like infection and stenosis at the venous anastomosis. The loss of access due to infection is significantly higher in thigh grafts than autologous thigh AV access (18.40% vs 1.61%, respectively). ² To mitigate these problems, autologous lower-limb vascular accesses have been proposed.

Great saphenous vein transposition (tGSV) to the superficial femoral artery has shown limited patency rates. In the largest reported cohort using this technique, a 30-day access loss rate of 37.4% was observed (21 out of 56 vascular accesses), with 20 cases resulting from thrombosis. The primary patency rate was 44% after 9 months of follow-up. ⁸ Another study reported a primary patency of only 7 months, with an average of three balloon percutaneous transluminal angioplasties required per patient, all of whom developed vein loop stenosis. Doppler ultrasound follow-up of the GSV demonstrated a natural resistance to dilation, typically increasing in diameter by only 1 to 2 mm and rarely achieving the recommended minimum diameter of 6 mm. ¹

Alternatively, the transposed femoral vein (tFV) offers superior patency rates. Antoniou et al. reported a 1-year primary and secondary patency of 83% and 93% for tFV, respectively, compared to 43% and 67% for thigh grafts. ² Bourquelot et al. documented 1-year and 9-year primary patency rates of 91% and 45% and secondary patency rates of 84% and 56%, respectively, in a study involving 72 cases of tFV. ⁹ Reported complications related to this technique include acute venous hypertension, oedema, compartment syndrome and distal ischaemia.^1,8 Adequate selection of patients, as described previously, alleviates these problems. Gradman et al. reported no ischaemic complications following the selective tapering or banding of the femoral vein after tFV and appropriate patient selection. ¹⁰ In our practice, we limit arteriotomy to 3–4 mm and conduct immediate clinical and ultrasound assessments to prevent steal syndrome.

Both tGSV and tFV procedures are associated with high complication rates and morbidity related to vein harvesting. Several studies have documented significant complications following saphenous vein harvesting, including haematoma, ipsilateral lower extremity oedema, increased risk of bleeding and pseudoaneurysm formation.^11,12 Most reports on tFV in the literature describe using a single, long incision through the thigh to harvest the femoral vein.^6,9,13,14 This approach contributes to wound complications, such as eschars, infections, lymphoceles and haematomas, which are significant drawbacks of tFV. Recent studies have reported complication rates of up to 37%, with some patients requiring extended or surgical wound care, prolonged hospitalisation or even loss of vascular access.^5,6,9,15 Wound-related complications remain an undesirable but anticipated risk in these patients. Two main factors contribute to this: patient-related factors (such as age, obesity and diabetes) and technique-related factors, primarily the length of the skin incision. Alcocer et al. reported that longer, single-skin incisions were associated with a higher number of complications (17 vs 7 cases) and longer maturation times (10.4 ± 5.6 weeks vs 6.1 ± 1.04 weeks) than short skip incisions. ¹⁶ Our optimised technique for femoral vein harvesting using short skip incisions and tunnelization using Matos Tunneler is based on the same principle we routinely employ for basilic vein transposition in the upper limb at our centre. ⁷ We recommend that a highly skilled vascular surgeon perform this approach, ideally one experienced in basilic or brachial vein transpositions using similar techniques. Harvesting the vein through short skin incisions carries a higher risk of damaging the femoral vein or avulsing its tributaries, which can result in difficult-to-control haemorrhage. The Matos Tunneler, a simple homemade device, has proven valuable for positioning the vein at the correct angle, reducing the risk of kinks and twists, common issues encountered during transposition. ⁷ The lateral tunnelization of the femoral vein through the anterior aspect of the thigh, followed by anastomosis to the distal femoral artery, eliminates the need for a venous-venous anastomosis and creates a straight path without loops, reducing the risk of stenosis. In our experience, a superficialised femoral vein diameter greater than 6 mm facilitates easy identification and allows puncture within 3 to 4 weeks. It also provides a greater length for puncture (typically 15 to 25 cm) and supports the rope-ladder puncture technique. These advantages improve comfort for both patients and nursing staff.

Pre-operative patient selection is a critical component of our approach, and we strongly advocate for carefully identifying candidates suitable for this procedure. All patients must undergo thorough screening to determine their eligibility for tFV.

In conclusion, femoral vein transposition is a viable alternative for patients with exhausted vascular access in the upper extremities. While this procedure is inherently complex, our experience suggests that short skip incisions present a manageable challenge for vascular surgeons experienced in basilic or brachial vein transpositions in the upper arm. The primary objective of this approach is to reduce wound complications and improve comfort for patients and dialysis nursing staff.