Endoscopic Superficialisation of Haemodialysis Arteriovenous Fistulas in Obese Patients - Safety, Feasibility, and Outcomes

Vascular access challenges in hemodialysis patients with superior vena cava syndrome

BACKGROUND

Superior vena cava syndrome in hemodialysis patients resulting from previous or current use of a tunneled central vein catheter is a rare but potentially severe condition. Two aspects have to be addressed during management and treatment: the restoration of central venous flow and the creation of an alternative vascular access to guarantee hemodialysis.

RESEARCH DESIGN

Conforming to the current guidelines and literature, we present a stepwise approach and discuss therapeutic options. The removal of the tunneled central vein catheter should be attempted and a native vascular access created whenever feasible.

RESULTS

First, an upper extremity AVF should be preserved or, as in our case, made functional. Endovascular treatment of CVSO should primarily consist of balloon dilatation. Placement of a stent or stent graft should be considered as a secondary option. HeRO graft placement may be considered in recurrent CVSO and recanalization with a Surfacer. LL-AVF or AVG need to be discussed and may be an alternative for certain HD patients when the risk of lower limb ischemia and infection is considered.

CONCLUSION

Several therapeutic options are available and the basic principles are well established in the literature, although the level of evidence is not high. Therefore, we propose a stepwise and interdisciplinary approach to guide the challenging decision-making process in SVC.

Lipectomy as an alternative for superficialization of autologous AVF in obese patients: experience of a referral center in Amazon

Background

The preferred vascular access for hemodialysis is a native arteriovenous fistula (AVF) because it offers the best results in the short and long terms, lower morbidity and mortality, and has additional advantages in relation to central venous catheters or arteriovenous grafts. However, obesity can present an additional challenge because of the barrier of subcutaneous cellular tissue covering the surface of the vein to be punctured.

Objectives

The authors review their experience with excision of subcutaneous tissue (lipectomy) overlying upper arm cephalic vein arteriovenous fistulas in obese patients.

Methods

Consecutive vascular access patients undergoing lipectomy for cannulation with difficult access because of vein depth were reviewed. Cephalic vein depth was measured by ultrasound in all cases.

Results

Twenty-two patients were reviewed (15 men and 7 women), with a mean body mass index of 34.0 kg/m2 (range: 28-40 kg/m2). Mean age was 58.4 years. The mean preoperative vein depth of 7.9 mm (range: 7.0-10.0 mm) was reduced to 4.7 mm (range: 3.0-6.0 mm) (P 0.01). The mean follow-up period for patients was 13.2 months. Four patients were lost to follow-up and four died during the period due to causes unrelated to vascular access.

Conclusions

Obesity should not be a limiting factor to creation of a native AVF, since lipectomy is a relatively simple option for superficialization, enabling functioning native and deep arteriovenous fistulas in obese patients.

Superficialization methods of arteriovenous fistula in obese patients: a review of the literature: Arteriovenous fistula in obese patients

BACKGROUND

The creation of an arteriovenous fistula (AVF) in obese patients with end-stage-renal-disease, might not lead to a successful hemodialysis session, partly due to excess adipose tissue overlapping the enlarged vein. This review summarizes the available evidence on superficialization methods in studies dealing with obese patients.

METHODS

An English-language literature search was undertaken in the MEDLINE/SCOPUS databases looking for publications that described procedures of salvaging autologous arteriovenous access in upper extremities of obese patients. Perioperative outcomes including technical and clinical success, mean vein depth reduction, wound complications and patency rates were compared within all identified techniques.

RESULTS

We identified 12 prospective and 8 retrospective studies. A total of 1149 patients with a mean age 57.2 (range: 49-68) years and a mean BMI 35.8 (range: 28.2-40.8) kg/m² underwent mainly radial-cephalic and brachial-cephalic AVF superficialization procedures [transposition, 54%; elevation, 11.1%; lipectomy, 26.1%; liposuction, 2.4%; implantation of a venous window needle guide device, 6.4%]. Technical success was similar between all methods (≥ 96%). However, successful cannulation was lower after liposuction and elevation (81.5 and 78.1% respectively). Transposition achieved lower mean vein depth reduction and clinical success when compared with lipectomy (4.9mm vs 8.8mm and 90% vs 92,7% respectively). Transposition and liposuction had the lowest and highest complication rate respectively (1.6% vs 40.8%). Primary and secondary patency rates were lower with liposuction (51.8 and 76.6% respectively), while lipectomy and elevation achieved the highest primary patency rates (68.3% and 71.6% respectively) at 12 months.

CONCLUSIONS

In obese patients, all superficialisation techniques report high technical success rates. Although limited by the design of individual published studies and lack of a standard for reporting outcomes, these results lead to satisfactory postoperative and early outcomes. In aggregate, lipectomy and transposition are more clinically effective and more durable procedures.

Early Experience with Sine Wave Technique for Superficialization of a difficult to cannulate Arterio Venous Fistula

OBJECTIVE

To highlight safety and efficacy of sine wave technique (SWT) in superficializing deep arterio venous fistula (AVF) and managing infiltrations and other complications.

METHODS

It is a single center observational study done from Jul 2017 to July 2020. All successive cases of deep AVFs, aneurysm / pseudoaneurysms of AVFs, and AVFs requiring open venoplasty were managed with SWT. Data was collected prospectively and analyzed. SWT is based on random pattern skin flaps. Using ultrasound, a line is marked on either side of centre line (AVF) at a distance of approximately 1.5-2 cm. A sine wave is drawn starting from either of the lines to the other with multiple crests and troughs. The base of flap should be double the height of the flap, that is, about 3-4 cm. Skin is incised and flaps are raised at level of AVF. Excess fat is removed. A sliver of unhealthy skin can be sacrificed if required. Flaps are sutured back to restore sine wave continuity.

RESULTS

SWT was used in a total of eleven patients. Median age was 58 years (range 10-67 years). Eight were females and three males. One was radio-cephalic and rest were brachio-cephalic AVFs. Eight AVFs were deep with median depth of 10.25mm (range 8-13mm), median body mass index of 25.5 kg/m² (range 23.9-26.5kg/m²), median vein diameter of 7 mm (range 6-8 mm), and median flow rate of 1137.5ml/min (range 650- 1380 ml/min). Out of eight, four AVFs presented with infiltration. In other three, SWT was used for exposing AVF to treat underlying pathology (one case each of aneurysm, pseudoaneurysm & stenosis). Ten cases were done under local or regional anesthesia and one under general anesthesia. There was no peri-operative mortality or loss of AVF. Transient limb oedema developed in one case. Median time to cannulate was 20 days (range 13-28 days). Median follow up was 13 months (range 6 - 31months). Cumulative patency at 18 months was 90% (95% CI 47.3%-98.53%) and 45 % (95% CI 9.9%-87.1%) at 24months and at the end of the study.

CONCLUSION

SWT is safe and effective in superficialization of deep / difficult to cannulate AVF as well a good approach to treat complications like infiltration. Post procedure cannulation time is reasonably short.