Radiocephalic Fistula Creation Research Articles

Impact of Isometric Exercise in Adolescents With End Stage Kidney Disease and Unsuitable Vessels For An Autologous Arteriovenous Fistula.

Despite the lack of calcification, to perform a native Arteriovenous Fistula (AVF) in young patients may pose a challenge due to small vessel diameter. We report a case series with no options of AVF in which vessel caliber improvement after isometric exercise allowed for radiocephalic fistula creation in all of them. Since 2017 to 2019, four patients were referred to our unit to create an AVF. Following a first assessment with physical examination and doppler ultrasound, none of them were eligible for AVF performance due to small vessel caliber. Once they were considered unsuitable for it, they started an isometric exercise program. Age ranged from 13 to 19years. There were three males and one female. Two were in predialysis and two in hemodialysis program. Initial diameters of the forearm cephalic vein and the radial artery respectively were: case A < 1.5/2.3mm, case B 1.5/1.6mm, case C < 1.5/1.6mm and case D 2.1/1.3mm. Median duration of exercise program was 13weeks (range 5-23). Post-exercise vessel diameters were: case A 2.7/2.3mm, case B 2.5/2mm, case C 2.8/1.8mm and case D 2.7/2mm. Radiocephalic AVF were performed in the four cases. After a median follow up of 19 months (range 9-30months), 75% of patients required further interventions but all of them had a functional AVF. In these four cases isometric preoperative exercise allowed the creation of AVF. Without the improvement in vessel diameter observed afterwards, all of them would have been rejected for AVF performance. Despite the high rate of adjunctive interventions needed, given the safety of the program and the potential risks of Central Venous Catheters, we consider it a valuable option.

Early and midterm patency of arteriovenous fistula for hemodialysis access using different techniques and their advantages and disadvantages.

This descriptive retrospective study was done to observe the different techniques of arteriovenous fistula creation for advantages and disadvantages, complications, and early and midterm patency. Fifty-three arteriovenous fistulas were created from September 2018 to August 2020 using four different techniques. Radio-cephalic arteriovenous fistula was usually the first option. Other techniques like brachio-cephalic arteriovenous fistula, radio-basilic arteriovenous fistula, and brachio-basilic arteriovenous fistula were used when the radio-cephalic fistula had thrombosed or could not be constructed due to small-sized cephalic vein in the forearm. The majority of patients (41 (77.35%)) underwent radio-cephalic fistula creation. Early patency was 38 (92.7%) in the radio-cephalic technique whereas it was 12 (100%) in the radio-basilic, brachio-cephalic, and brachio-basilic techniques combined. The midterm patency was 32 (78%) in the radio-cephalic technique, 5 (83%) in the brachio-cephalic technique, 3 (75%) in the radio-basilic technique, and 1 (50%) in the brachio-basilic technique. Radio-basilic and brachio-cephalic are alternative techniques for fistula creation after radio-cephalic depending upon the size of the basilic vein in the forearm or cephalic vein in the cubital fossa or arm. The radio-basilic technique may have advantages over the brachio-cephalic technique which need to be further evaluated. Proximal fistulas like brachio-basilic and brachio-cephalic are more commonly associated with limb edema.

MO773THE VASCULAR REALITY BEHIND ULTRASOUND VASCULAR MAPPING: WHICH FACTORS PREDICT THE BEST CANDIDATES FOR RADIOCEPHALIC ARTERIOVENOUS FISTULA?

Abstract Background and Aims Vascular accesses (VA) are key components for efficient hemodialysis. Arteriovenous fistulas (AVF) are recommended over arteriovenous graft (AVG), but deciding the type and location of a VA is challenging. Preoperative vascular mapping before surgical creation of VA, especially trough ultrasound (US), is helpful in this decision, contributing to improve AVF e AVG outcomes. Our study aims to identify patient factors associated with appropriate arterial US parameters that predict feasibility for radiocephalic fistula creation. Method We analyzed a cohort of chronic kidney disease patients who underwent US vascular mapping for preoperative planning of dialysis access from 2019 to 2020, in a tertiary referral center. Patients were characterized based on its demographical characteristics, and the presence of diabetes, hypertension, obesity, and smoking. Arterial indicators were analyzed by ultrasound techniques in both upper arms, including radial, ulnar and brachial arteries. Those indicators included arterial diameter, calcification, doppler wave form, and pulse wave velocity. Continuous variables were recorded as means (±SD) for normally distributed data and as medians (interquartile ranges) for nonnormally distributed data. Comparisons were made using t tests or Wilcoxon rank sum tests as appropriate. Categorical variables were examined by frequency distribution and recorded as proportions. Comparisons were made using the x2 test. Unadjusted and adjusted multivariate logistic regression models were fitted to identify predictors for a good candidate for radiocephalic arteriovenous fistula. Results A total of 252 patients were included. The mean age was 65±16 years, 144 (57%) were male, 211 (84%) where white, 40 (16%) were black, and 1 (0.4%) was asian. Most had arterial hypertension (205, 81%), 98 (39%) had diabetes mellitus, 89 (35%) were smokers, and 72 (29%) were obese. The majority of patients were attending for the first VA (186; 74%). Most patients were considered appropriate candidates for arteriovenous fistula creation (207, 82%), whereas 45 (18%) were assigned to PTFE graft. Obesity and male sex were found to be predictors for being a good candidate for radiocephalic arteriovenous fistula in a multivariate logistic regression model adjusted for age, hypertension, and diabetes (OR 3.21, CI 95% 1.63-6.32, p-value 0.001 and OR 2.09, CI 95% 1.07-4.08, p-value 0.031, respectively). Figure 1 presents the arterial indicators analyzed during ultrasound mapping, including both upper limbs. Conclusion Our results show that obesity and male sex are predictors for radiocephalic arteriovenous fistula creation. While female sex has long been known to be a risk factor for VA failure, possibly because of worse arterial indicators, an association between obesity and higher probability of distal AVF creation has not been established yet. Comparison between arterial indicators in obese and nonobese patients shows that obese patients generally have better arterial indicators, especially higher pulse wave velocities, and less arterial calcification. Given that some studies show an association between obesity and shorter fistula survival (due to higher secondary failure rate), our results may come as. A possible explanation for this difference is that obesity may exert a physical protective effect of the forearm vascular bed against iatrogenic damage (blood sampling and vessel cannulation). Besides that, factors other than vascular indicators may contribute to ulterior VA failure, like the proinflammatory state in obese patients and its consequent myointimal hyperplasia. However, our conclusions are based on preoperative findings, and not on VA outcomes, especially its patency and complications. Moreover, which further help to determine the better location for a VA creation, were not evaluated in this study.

Anatomic suitability for commercially available percutaneous arteriovenous fistula creation systems

ObjectiveThe Food and Drug Administration recently approved two percutaneous arteriovenous fistula creation systems: the Ellipsys vascular access (EL) system and WavelinQ EndoAVF (WQ) system. Although the initial clinical trials of each system have demonstrated a high success rate, little detail on anatomic suitability was provided. We sought to determine the real-world applicability of the EL and WQ systems by studying them in a single representative cohort. MethodsAll patients receiving a first-time arteriovenous access consultation at a single Veterans Affairs institution underwent extensive vein mapping of the bilateral upper extremities. Anatomic suitability was assessed in accordance with the manufacturer's instructions for use (IFU), and clinical usability was determined using additional published anatomic guidelines. The suitability for radiocephalic fistula (RCF) creation was also assessed. To estimate how often these systems would be used in practice, a clinical algorithm was created, with a preference for RCF creation, followed by percutaneous arteriovenous fistula (pAVF) creation, surgical fistula creation at the elbow, and, finally, graft placement. ResultsDuring the study period, 116 upper extremities were measured in 58 male patients. Per the IFU, the rate of extremity suitability was 93% and 52% for the WQ and EL systems, respectively (P < .0001). In the same population, 32% of the extremities had acceptable anatomy for RCF creation. The overall clinical usability of these systems using more recent published guidelines was 55% for the WQ system and 44% for the EL system (P = .09). The usability of both pAVF systems was most limited by the size of the deep perforating cubital vein. The proximity of the antecubital perforator vein and proximal radial artery additionally limited EL usability. Based on the clinical algorithm, initial access creation would have been RCF creation for 31% of the cohort, followed by the WQ (32%), the EL (23%), surgical fistula creation at the elbow (18%), and graft placement (17%). ConclusionsAnatomic suitability was greater for WQ than for EL when considering only the IFU. Once the full requirements for pAVF creation were considered, we found no significant differences in usability between the two systems. Anatomic analysis showed that pAVF creation can constitute a substantial part of a hemodialysis access practice.

Retrograde transradial Approach for Hemodialysis Access Intervention: A Single-Center Study

Perianastomotic stenosis is a common scenario after creation of arteriovenous fistula for hemodialysis. Most of the interventionists prefer transvenous approach. But transradial approach can easily visualize radial artery and cephalic venous tree up to central vein. This retrospective study was performed from November 2012 to January 2017 in Ibn Sina Hospital, Dhanmondi, Dhaka. Total patients undergoing hemodialysis access were 148 (male 74, female 74, male-female ratio 1:1). Number of radiocephalic fistula was 95 (64%), brachiocephalic fistula 50 (34%) &amp; others 3 (2%). Most of the punctures were done by palpation. Sometimes puncture was made by ultrasonogram guidance. Puncture needle size was 21 gauge, 2.5cm or 4cm long. Sheath size was 6 F x 4 cm or 7 F x 4cm. Majority of the cases (140) were successfully approached through retrograde transradial route. Few cases (8) were approached through retrograde venous route due to thrombosis of radial artery for previous intervention or creation of radiocephalic fistula in an end to end fashion. It was concluded that retrograde transradial approach to dilate perianastomotic stenosis as well as outflow vein is a good option.&#x0D; Bangladesh Heart Journal 2020; 35(1) : 54-60

Effect of Distal Cephalic Vein Ligation on Primary Patency Rates and Proximal Flow Rates in Distal Radiocephalic Fistula.

Introduction:The Brescia-Cimino radiocephalic fistula, originally devised as a side-to-side anastomosis, is simple to perform and provides a smooth vein–artery interface but requires greater mobilization for vein–artery approximation than does the end-to-side approach. Distal cephalic vein ligation is performed to prevent venous hypertension. The study aims to assess primary patency at one month following distal side-to-side radiocephalic fistula creation with and without distal cephalic vein ligation, to assess the effect of distal cephalic vein ligation on flow rates at one month, and to document the occurrence of venous hypertension over one year follow up.Method:A total of 100 patients requiring vascular access for hemodialysis were assigned to side-to-side anastomosis with and without distal cephalic vein ligation. Follow up Doppler exam was performed at one month for assessment of patency and flow rates and after one year clinical exam to document venous hypertension and the need for revision surgery. The quantitative and qualitative variables were evaluated using student t test and chi square test, respectively.Results:The patency rates of distal ligation and no ligation groups were 86.4% and 85.4%, respectively. The proximal flow rates of distal ligation and no ligation groups were 1192+/−812 ml/min and 1217+/−796 ml/min, respectively. The difference was not statistically significant (P > 0.05). Only two cases (5%) with no ligation required revision ligation within one year of surgery.Conclusion:Distal cephalic vein ligation does not increase the proximal cephalic flow rates and primary patency rates after one month. However, venous hypertension was associated in 5% of nonligated cases at one year follow up.

The impact of pre-existing radial artery pathology by histological assessment on the maturation, function and patency of the radiocephalic fistula for hemodialysis.

We prospectively analyzed the effect of preexisting structural changes of the radial artery (RA) wall by histological examination on the wrist radiocephalic fistula (RCF) outcomes. During RCF creation, one segment of the RA wall was collected and its histomorphometric analysis was performed. The RCF function was evaluated by measuring blood flow rate. At the end of follow-up, 75.7% of the thirty-seven patients enrolled were performing hemodialysis by using their successful RCF and 24.3% of them showed early RCF failure. Compared to patients with a healthy RA, the RCF of those with medial RA microcalcification reached up a lower flow and a shorter primary patency (P=0.005 and P=0.040, respectively). The RA microcalcification was predictive of the RCF function (coefficient -614.9, 95% CI: -994.7 to -235.1, P=0.003). Compared to patients with successful RCF, those with failed RCF had a greater frequency of weak RCF thrill after releasing the clamps (P=0.045). Dependence on hemodialysis during RCF placement was predictive of its early failure (OR: 23.2, 95% CI: 1.76 to 306.9, P=0.017). Both having at least one cardiovascular comorbidity (HR 4.30, 95% CI: 1.29 to 14.39, P=0.018) and a thicker media layer of the RA (HR 1.60, 95% CI: 1.87 to 2.15, P=0.002) were predictive of primary RCF patency. The function and survival of the successful RCF were related to preoperative RA abnormalities such as microcalcification and media layer thickness. Both dependence on hemodialysis during RCF placement and an attenuated RCF thrill were associated with early RCF failure.

Modified technique of end to side distal radio-cephalic shunt to overcome juxta-anastomotic stenosis

Background: Juxta-anastomotic stenosis (JAS) is one of the predominant causes of arteriovenous fistula (AVF) failure, with the reported incidence of 65%, so that technical modification to alter the outflow vein configuration using the modified technique has been applied to prevent JAS and improve AVF maturation. The aim of the study to evaluate the modified technique of end-to-side distal radiocephalic A-V fistula regarding maturation, patency rate and the resultant juxta-anastomotic stenosis.Methods: This prospective study was carried out on 80 patients with end stage renal disease (ESRD) at vascular surgery unit in general surgery department, Menoufia university hospital that prepared for dialysis. 40 patients "intervention group" underwent the modified technique to establish a functioning radiocephalic fistula; the other group (40 patients, control group) had the conventional technique of end to side radiocephalic fistula. Follow up of patients was over 6 months regarding function, patency rate and development of juxta-anastomotic stenosis.Results: There was statistically significant difference between 2 groups regarding primary failure, patency and JAS. Primary failure was detected in 2 patients in group A and in 5 patients in group B (p-value is 0.04). Considering patency rate, after 3 months the ratio between group A and group B was 37:34 with significant P value of 0.02, and after 6 months the ratio was 35:33 with P value of 0.03. Regarding JAS, by the end of follow up period, 4 patients diagnosed with JAS in group A, while group B had 8 patients, with p value of 0.01.Conclusions: Modified technique of end to side anastomosis for primary radio-cephalic fistula creation has better patency rate and low incidence of JAS than conventional method.

Conventional method versus no-touch technique in radiocephalic arteriovenous fistula

Objectives The aim was to evaluate the feasibility of no-touch technique (NTT) in radiocephalic fistula and to compare conventional method with NTT in the creation of radiocephalic fistula regarding the rate of complication, failure of maturity, and patency rate. Background Radiocephalic fistula is consider the first fistula to be created; however, it has a higher failure rate. NTT represents an attractive option for performing radiocephalic fistula. Patients and methods This is a prospective comparative study done on 80 patients with end-stage renal disease who were prepared for dialysis. Half of the patients were operated by NTT and the other half by conventional technique at vascular surgery unit in department of general surgery, Menoufia University Hospital, between November 2016 and April 2018. Results A total of 80 patients who had end-stage renal disease underwent radiocephalic arteriovenous fistula: half of them with conventional (Brescia and Cimino) technique and the other half with no-touch method. The primary failure rate in NTT (7.5%) was not statistically significantly different from the conventional method (17.5%). The primary patency also had no statistically significant difference during the follow-up period at 1 and 3 months between the two methods, but NTT at 6 months had better primary and secondary patency rates than conventional method. There was no difference in infection and pseudoaneurysm rates between the two methods. Conclusions The results of this study indicate that NTT can be used for primary radiocephalic fistula surgery and showed better results than conventional method in the long-term follow-up.

One-stage operation for superficialization of native radio-cephalic fistula in obese patients.

The population of obese patients is increasing in general and also at hemodialysis initiation. For successful cannulation of arteriovenous fistula, the National Kidney Foundation-Dialysis Outcome Quality Initiative guidelines suggest that the required maturation parameters are at a depth of <6 mm. There are several reports describing two-stage superficialization of arteriovenous fistulas in obese cases. Therefore, we investigated the utility and complications of one-stage superficialization of radio-cephalic fistula. From January 2011 to March 2017, we simultaneously performed forearm radio-cephalic fistula creation and superficialization of the cephalic vein for 10 patients having obesity (body mass index > 30 kg/m2) and deep cephalic vein (>6 mm). Initially, an arteriovenous anastomosis was created at an appropriate site. Subsequently, an 8-10 cm longitudinal skin incision was made along the lateral aspect of the forearm cephalic vein. The cephalic vein was identified and exposed. The cephalic vein was repositioned superficially. The mean age of the patients was 53 years (range: 40-72 years) and the mean body mass index was 40.2 kg/m2 (33.1-59.7 kg/m2). The cause of renal failure in eight patients was diabetic nephropathy, and in two patients, it was unknown. After the procedure, vein depth became 3.4 mm (1.9-4.6 mm) from 8.2 mm (6.0-13.4 mm). All patients who initiated dialysis underwent successful two-needle cannulation. Primary patency rate was 71.4% at 12 months (two patients underwent percutaneous transluminal angioplasty) and secondary patency rate was 100%. There was one procedure-related complication and delayed wound healing, which was improved by observation without antibiotics. This small series of patients indicates that one-stage superficialization of radio-cephalic fistula is a safe and effective option to start hemodialysis in obese subjects.

Brachiocephalic Arteriovenous Fistula for Hemodialysis through the Median Antecubital Vein.

In patients unsuitable for radiocephalic fistula creation, the next option is brachiocephalic fistula. In such patients, we exploited the venous interconnections in the cubital fossa for median cubital vein-Brachiocephalic arteriovenous fistula (AVF) creation. In this article, we describe our experience in the creation of such technical variant of the brachiocephalic fistula AVF, its success and associated complications. A retrospective review of such AVF created between September 2014 and August 2015 was done. The data collected included demographics, co-morbidities, basic disease, operative details, patency, complications, and mortality. A total of 68 vascular access surgeries were done which included 26 (38.2%) brachiocephalic AVF using the median antecubital vein. The mean cephalic vein diameter and mean flow rate were 7.18 mm and 1415 ml/min, respectively 2 months after fistula creation. The primary and secondary failure rates were 3.87% and 7.69% respectively. Complications included aneurysm (7.69%), edema (19.23%), hematoma (11.53%), and wound infection (3.8%). Using reverse flow in the median antecubital vein is a safe and simple way to perform brachiocephalic AVF before brachiobasilic AVF and grafts.

A Single Center Study of Clinical Success in Radiocephalic Fistula Creation

To compare standard methods (control) with a new protocol for radiocephalic fistula (RCF) creation involving ultrasound vein mapping by the surgeon in the operating room, ligation of cephalic vein branches in the lower forearm, and use of a tourniquet for the arteriovenous anastomosis. This is a retrospective cohort study of patients who underwent radiocephalic fistula creation between April 2008 and March 2010 in a regional vascular center. Patients were identified retrospectively by reviewing hospital operating room and office billing records. The electronic charts of all patients were reviewed. The primary endpoint was functional RCF patency at last follow-up. A total of 118 patients underwent arteriovenous (AV) fistula creation by 3 surgeons during the two-year study period. Of these, 59 patients underwent RCF creation, 33 of whom were managed using the new protocol. The two groups were comparable, except for age (66 in the study group vs. 60 in the control group, P=.04). Tourniquet use shortened operative time from 48 to 36 minutes (P=.04). Functional patency was 82% vs 77% (P=.64). The new protocol for RCF creation results in shorter operative times and high functional patency rates.