Proximalization of arterial inflow with adjunctive arterial pressure measurements for management of hemodialysis access-induced distal ischemia

Hemodialysis access-induced distal ischemia (HAIDI) is an uncommon, yet potentially devastating, complication of hemodialysis access surgery. Management of HAIDI depends on the access' volume flow and may involve banding, proximalization of arterial inflow, revision using distal inflow, distal revascularization interval ligation, or access ligation. Various adjunctive techniques have been used to confirm improved distal arterial flow intraoperatively. Here, we present a case of a patient with grade 3 HAIDI treated with proximalization of arterial inflow technique with the adjunctive use of intra-arterial pressure gradient measurements.

Chronic Dialysis Therapies

While both in-center and home dialysis modalities have improved life expectancy for people with end-stage kidney disease and have served as a bridge to eventual kidney transplantation, kidney health care providers must be keenly aware of the potential complications associated with these therapies. The following questions aim to shed light on some of the more important potential physiological consequences and medical dilemmas associated with the three primary dialysis modalities including in-center hemodialysis, home hemodialysis, and peritoneal dialysis. Moreover, we hope to highlight that caring for those requiring dialytic therapy necessitates a significant breadth of understanding in other core internal medicine disciplines beyond nephrology itself, including cardiovascular, infectious, and musculoskeletal disease entities.

Color Doppler ultrasound evaluation of arteriovenous grafts for hemodialysis

Although arteriovenous fistula (AVF) continues to be the vascular access of choice for the hemodialysis, arteriovenous graft (AVG) can be the best choice in certain categories of patients and could have several advantages over AVF in a "patient centered approach" to vascular access. In the clinical management of prosthetic fistulas, color Doppler ultrasound (CDU) is the imaging method of choice for identifying stenosis and other AVG complications. In this review, besides highlighting the pivotal role of CDU in the diagnosis of AVG complications, we will underline the key role that ultrasound can play in identifying those stenosis most likely to cause AVG thrombosis. Furthermore, we will emphasize the support that CDU can play in distinguishing the different types of grafts and prosthetic devices such as stent-grafts, in identifying AVG with lower survival, CDU utilities and limitations in the evaluation of freshly-implanted grafts, the different sites available for AVG volume flow measurement and their use based on the configuration of the prosthesis, the time interval elapsed from the surgical intervention and the integrity of the prosthetic walls.

[Application of prophylactic flow restriction in brachiocephalic arteriovenous fistulas]

OBJECTIVES

To investigate the effects of prophylactic flow restriction for brachiocephalic arteriovenous fistula on postoperative high-flow-related complications and patency rate in patients undergoing hemodialysis.

METHODS

Clinical data of patients with end-stage renal disease who underwent brachiocephalic arteriovenous fistula surgery for hemodialysis from February 2017 to May 2022 in Department of Nephrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine were retrospectively analyzed. During surgery, a 4-5 mm vascular suture loop was placed around the vein near the anastomosis as a flow restriction device in 43 patients (flow restriction group), while 42 patients did not receive the prophylactic flow restriction ring (control group). All patients were followed up for 1 to 5 years. The incidence rates of complications related to the hemodialysis access pathway, including distal ischemia syndrome, the formation of arteriovenous fistula aneurysms, thrombus, high-flow congestive heart failure, anastomosis of the vein within 1 cm of the anastomosis and cephalic arch stenosis, were compared between the two groups. The natural blood flow rate of the arteriovenous fistula, anastomosis size, the internal diameter of the vein near the anastomosis, primary patency rate, assisted primary patency rate, and secondary patency rate of the arteriovenous fistula, were also evaluated and compared between the two groups. Logistic regression analysis was used to investigate the factors affecting arteriovenous fistula patency rates, as well as the impact of the flow-restricting ring on postoperative factors.

RESULTS

Ultrasound measurements showed that the internal diameter of the vein at the site of the flow restriction ring in the flow restriction group was (3.7±0.6) mm at three months postoperatively, which was significantly smaller than the internal diameter of the narrowest part of the vein near the anastomosis in the control group [(4.1±1.0) mm, t=－2.416, P<0.01]. The postoperative anastomotic diameter and natural blood flow rate of the arteriovenous fistula in the flow restriction group were both significantly lower than those in the control group (both P<0.05). Furthermore, the incidence rates of various complications in the flow restriction group were significantly lower than those in the control group (all P<0.05). At 6, 12, and 24 months postoperatively, the primary patency rate and assisted primary patency rate in the flow restriction group were significantly higher than those in the control group (both P<0.05), while there was no significant difference in secondary patency rates between the two groups (P>0.05). Binary logistic regression analysis indicated that age, diabetes, and natural blood flow rate of the arteriovenous fistula at 3 months postoperatively were independent risk factors for primary patency rate, while the flow restriction for brachiocephalic arteriovenous fistula was an independent protective factor for primary patency rate (P<0.01 or P<0.05). The application of flow restriction was negatively correlated with anastomotic diameter at 6 and 12 months, natural arteriovenous fistula blood flow, and the incidence rates of cephalic arch stenosis and aneurysm formation (all P<0.05).

CONCLUSIONS

The prophylactic constriction during brachiocephalic arteriovenous fistula surgery in patients undergoing hemodialysis can limit the size of the anastomosis and postoperative arteriovenous fistula blood flow, reducing complications such as cephalic arch stenosis and high-flow heart failure, and increasing primary patency rates of arteriovenous fistula and delay the reintervention of the fistula.

Impact of Vascular Access Flow Suppression Surgery on Cervical Artery Circulation: A Retrospective Observational Study

Vascular access (VA) flow suppression surgery augments VA flow resistance and can increase other circulation flows hindered by high-flow VA. However, whether VA flow suppression surgery affects cervical circulation has rarely been reported. We aimed to determine the effect of VA flow suppression surgery on the cervical circulation in patients with high-flow VA. This single-center, retrospective, observational study included 85 hemodialysis patients who underwent VA flow suppression surgery at the Kanno Dialysis and Access Clinic between 2009 and 2018. Blood flow in the VA, bilateral vertebral arteries, and common carotid artery was measured before and after VA flow suppression surgery. The VA flow decreased from 1548 mL/min to 693 mL/min postoperatively. The flow of the vertebral artery on the VA side increased from 55 mL/min to 81 mL/min. The flow in the bilateral common carotid arteries also increased. Patients whose symptoms improved postoperatively showed better improvement in the vertebral artery on the VA side. VA flow suppression surgery in patients with high-flow VA increases the flow of the vertebral artery on the VA side and of the bilateral common carotid arteries. High-flow VA can hinder the vertebral and common carotid circulation.

Hemodialysis Access: US for Preprocedural Mapping and Evaluation of Maturity and Access Dysfunction

Patients with kidney failure require kidney replacement therapy. While renal transplantation remains the treatment of choice for kidney failure, renal replacement therapy with hemodialysis may be required owing to the limited availability and length of time patients may wait for allografts or for patients ineligible for transplant owing to advanced age or comorbidities. The ideal hemodialysis access should provide complication-free dialysis by creating a direct connection between an artery and vein with adequate blood flow that can be reliably and easily accessed percutaneously several times a week. Surgical arteriovenous fistulas and grafts are commonly created for hemodialysis access, with newer techniques that involve the use of minimally invasive endovascular approaches. The emphasis on proactive planning for the placement, protection, and preservation of the next vascular access before the current one fails has increased the use of US for preoperative mapping and monitoring of complications for potential interventions. Preoperative US of the extremity vasculature helps assess anatomic suitability before vascular access creation, increasing the rates of successful maturation. A US mapping protocol ensures reliable measurements and clear communication of anatomic variants that may alter surgical planning. Postoperative imaging helps assess fistula maturation before cannulation for dialysis and evaluates for early and late complications associated with arteriovenous access. Clinical and US findings can suggest developing stenosis that may progress to thrombosis and loss of access function, which can be treated with percutaneous vascular interventions to preserve access patency. Vascular access steal, aneurysms and pseudoaneurysms, and fluid collections are other complications amenable to US evaluation. ©RSNA, 2023 Supplemental material is available for this article. Test Your Knowledge questions for this article are available through the Online Learning Center.

ACR Appropriateness Criteria® Dialysis Fistula Malfunction

The creation and maintenance of a dialysis access is vital for the reduction of morbidity, mortality, and cost of treatment for end stage renal disease patients. One's longevity on dialysis is directly dependent upon the quality of dialysis. This quality hinges on the integrity and reliability of the access to the patient's vascular system. All methods of dialysis access will eventually result in dialysis dysfunction and failure. Arteriovenous access dysfunction includes 3 distinct classes of events, namely thrombotic flow-related complications or dysfunction, nonthrombotic flow-related complications or dysfunction, and infectious complications. The restoration of any form of arteriovenous access dysfunction may be supported by diagnostic imaging, clinical consultation, percutaneous interventional procedures, surgical management, or a combination of these methods. This document provides a rigorous evaluation of how variants of each form of dysfunction may be appraised and approached systematically. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Dialysis Access-Associated Steal Syndrome and Management

Dialysis-associated steal syndrome (DASS) occurs in 1-8% of hemodialysis patients with arteriovenous (AV) access. Major risk factors include use of the brachial artery for access creation, female sex, diabetes, and age > 60 years. DASS carries severe patient morbidity including tissue or limb loss if not recognized and managed promptly, as well as increased mortality. Diagnosis of DASS requires a directed history and physical exam supported by non-invasive testing. Prior to definitive therapy, detailed arteriography, fistulography, and flow measurements are performed to delineate underlying etiologies and guide management. To optimize success, DASS treatment should be individualized according to access location, underlying vascular disease, flow dynamics, and provider expertise. Possible causes of DASS include extremity inflow or outflow arterial occlusive disease, high AV access flow rate, and reversal of distal extremity arterial blood flow; DASS may also exist without any of the prior features. Depending on the DASS etiology, various endovascular and/or surgical interventions should be considered. Regardless, in the majority of patients presenting with DASS, access preservation can be achieved.

The Role of Ultrasound Examination in the Assessment of Suitability of Calcified Arteries for Vascular Access Creation-Mini Review

Arterial calcifications are present in 20-40% of patients with end-stage kidney disease and are more frequent among the elderly and diabetics. They reduce the possibility of arterio-venous fistula (AVF) formation and maturation and increase the likelihood of complications, especially distal ischemia. This review focuses on methods for detecting arterial calcifications and assessing the suitability of calcified arteries for providing inflow before the construction of an AVF. The importance of a clinical examination is stressed. A grading system is proposed for quantifying the severity of calcifications in the arteries of the arm with B-mode and Doppler ultrasound exams. Functional tests to assess the suitability of the artery to provide adequate inflow to the AVF are discussed, including Doppler indices (peak systolic velocity and resistive index during reactive hyperemia). Possible predictors of the development of distal ischemia are discussed (finger pressure, digital brachial index, acceleration and acceleration time), as well as the outcomes of AVFs placed on calcified arteries. It is concluded that a noninvasive ultrasound examination is probably the best tool for a morphologic and functional assessment of the arteries. An arterial assessment is of utmost importance if we are to create distal radiocephalic AVFs in our elderly patients whenever possible without burdening them with futile surgical attempts.

Proximalization through one incision of a wrist arteriovenous fistula and distal revascularization with interval ligation

In the setting of ischemic steal syndrome with tissue loss, patients with radiocephalic fistulas have limited options to preserve their conduit and treat their ischemic symptoms. To address this, we have proposed the technique of proximalization through one incision of a wrist arteriovenous fistula (POWR) with distal revascularization with interval ligation (DRIL) procedure. In the present retrospective, single-center, case series, we evaluated the outcomes of three patients with radiocephalic fistulas who had undergone POWR DRIL from 2017 to 2021. Their ischemic symptoms were monitored for regression. All three patients showed signs of regressing ischemia. The POWR DRIL represents an efficient procedure to address tissue loss and preserve the autogenous conduit.

ASDIN white paper: Management of cephalic arch stenosis endorsed by the American Society of Diagnostic and Interventional Nephrology

Brachiocephalic arteriovenous fistulas (AVF) makeup approximately one third of prevalent dialysis vascular accesses. The most common cause of malfunction with this access is cephalic arch stenosis (CAS). The accepted requirement for treatment of a venous stenosis lesion is ⩾50% stenosis associated with hemodynamically abnormalities. However, the correlation between percentage stenosis and a clinically significant decrease in access blood flow (Qa) is low. The critical parameter is the absolute minimal luminal diameter (MLD) of the lesion. This is the parameter that exerts the key restrictive effect on Qa and results in hemodynamic and functional implications for the access. CAS is the result of low wall shear stress (WSS) resulting from the effects of increased blood flow and the unique anatomical configuration of the CAS. Decrease in WSS has a linear relationship to increased blood flow velocity and neointimal hyperplasia exhibits an inverse relationship with WSS. The result is a stenotic lesion. The presence of downstream venous stenosis causes an inflow-outflow mismatch resulting in increased pressure within the access. Qa in this situation may be decreased, increased, or within a normal range. Over time, the increased intraluminal pressure can result in marked aneurysmal changes within the AVF, difficulties with cannulation and the dialysis treatment, and ultimately, increasing risk of access thrombosis. Complete characterization of the lesion both hemodynamically and anatomically should be the first step in developing a strategy for management. This requires both access flow measurement and angiographic imaging. Patients with CAS present a relatively broad spectrum as relates to both of these parameters. These data should be used to determine whether primary treatment of CAS should be directed toward the anatomical lesion (small MLD and low Qa) or the pathophysiology (large MLD and high Qa).

Dialysis associated steal syndromes. A narrative review

BACKGROUND

To review contemporary concepts in the genesis of Dialysis Access Steal Syndrome (DASS) and its current management.

METHODS

An electronic search of literature from 1960 to 2020 in Pubmed and the Cochrane library was conducted and practice guidelines were examined. Search terms included dialysis, steal, ischemia, access and ESRD. Clinical presentation, pathophysiology, risk factors, diagnostic techniques and management outcomes of extremity ischemia following dialysis access creation were reviewed.

RESULTS

Symptomatic steal occurs in 4-10% of patietns after creation of hemodialysis access creation. Risk factos include brachial based fistula, diabetes, female sex, coronary heart disease, cerebrovascular disease, tobacco use, age more than 60 and hypertension. Diagnosis is mainly clinical and can be aided by non invasive testing. Correction o finflow stenosis, Distal revasulatisation with interval ligation, revision using distal inflow or other techniques are useful for fistula preservation.

CONCLUSIONS

Dialysis associated steal syndromes have a complex haemodynamic causation. Clinical presentation is diagnostic; however when the diagnosis is uncertain adjunctive noninvasive perfusion tests, duplex and other imaging amy be required. Management is guided by anatomic, patient and disease-related considerations.

ASDIN white paper: Assessment and management of hemodialysis access-induced distal ischemia by interventional nephrologists

Although not common, hemodialysis access-induced distal ischemia is a serious condition resulting in significant hemodialysis patient morbidity. Patients with signs and symptoms suggestive of hand ischemia frequently present to the general and interventional nephrologist for evaluation. In order to care for these cases, it is necessary to understand this syndrome and its management. Most cases can be managed conservatively without intervention. Some cases requiring intervention may be treated using techniques within the scope of practice of the interventional nephrologists while other cases require vascular surgery. In order for the interventional nephrologists to evaluate and manage these cases in a timely and appropriate manner, practice guidelines are presented.

Determining the incidence of needle-related complications in hemodialysis access: We need a better system

INTRODUCTION

Hemodialysis access complications are common. We hypothesize that many of these complications can be traced back to needle-related injury from routine cannulation practices or inadvertent cannulation injuries. We set out to compare the rates of hemodialysis access complications under prior and current diagnosis coding systems, determine the incidence of needle-related complications for hemodialysis access, and describe the association of needle-related complications and resulting interventions.

METHODS

Arteriovenous graft and arteriovenous fistula placements occurring in the first 6 months of 2014 and 2016 were identified in the United States Renal Data System Medicare claims data. Placements were followed until end of hemodialysis access life or end of the calendar year. Diagnoses and resulting interventions occurring during placement life were identified and mapped to needle-related complication terms.

RESULTS

Almost 30,000 placements for 27,000 patients were followed in each year, with 67% of all accesses placed being arteriovenous fistula and 33% arteriovenous graft. In both years, 75% of arteriovenous fistulae and arteriovenous grafts required one or more interventions. Stenosis and thrombosis were the most common complications diagnosed and treated (41% and 16%, respectively); however, potential needle-related complications accounted for 6% of this dataset.

DISCUSSION

International Classification of Diseases, 9th Revision, was inadequate for determining the incidence of specific hemodialysis access complications or needle-related complications. International Classification of Diseases, 10th Revision, introduced several more hemodialysis access diagnoses but is still subject to coding confusion and catch-all coding for a variety of common and otherwise well-defined complications, suggesting that the true incidence of needle-related complications is buried in the non-specific diagnosis codes. These findings mark the clear need for an improved diagnosis coding system that consistently represents all common hemodialysis access complications.

Consensus document for ultrasound training in the specialty of Nephrology

Ultrasound is an essential tool in the management of the nephrological patient allowing the diagnosis, monitoring and performance of kidney intervention. However, the usefulness of ultrasound in the hands of the nephrologist is not limited exclusively to the ultrasound study of the kidney. By ultrasound, the nephrologist can also optimize the management of arteriovenous fistula for hemodialysis, measure cardiovascular risk (mean intimate thickness), implant central catheters for ultrasound-guided HD, as well as the patient's volemia using basic cardiac ultrasound, ultrasound of the cava inferior vein and lungs. From the Working Group on Interventional Nephrology (GNDI) of the Spanish Society of Nephrology (SEN) we have prepared this consensus document that summarizes the main applications of ultrasound to Nephrology, including the necessary basic technical requirements, the framework normative and the level of training of nephrologists in this area. The objective of this work is to promote the inclusion of ultrasound, both diagnostic and interventional, in the usual clinical practice of the nephrologist and in the Nephrology Services portfolio with the final objective of offering diligent, efficient and comprehensive management to the nephrological patient.

Avoiding hemodialysis access-induced distal ischemia

Timely creation and maintenance of a safe and reliable vascular access is essential for hemodialysis patients with end-stage renal disease. Hemodialysis access-induced distal ischemia (HAIDI) is a recognized complication of arteriovenous fistulas and grafts that may result in serious or even devastating consequences. Avoiding such complications is clearly preferred over treatment of HAIDI once established. Proper recognition of patients at increased risk of HAIDI includes careful pre-operative evaluation of the patient's medical and surgical history along with physical examination and imaging to determine a plan for creating a functional permanent access while minimizing the risk of distal ischemia. Our aim is to review identifying characteristics of individuals at risk of HAIDI and provide recommendations regarding pre-operative assessment. Vascular access options and techniques are suggested for establishing a functional vascular access without distal ischemia for such patients.

Severe hemodialysis access-induced distal ischemia may be associated with poor survival

BACKGROUND

Some hemodialysis patients develop hemodialysis access-induced distal ischemia due to insufficient loco-regional perfusion pressure and consequent poor arterial flow. We hypothesized that patients with severe hemodialysis access-induced distal ischemia had worse survival compared with patients with mild or no hemodialysis access-induced distal ischemia.

METHODS

This single-center retrospective observational cohort study included three groups of prevalent hemodialysis patients with an upper extremity vascular access between 2006 and 2018. Symptomatic patients had signs and symptoms of hemodialysis access-induced distal ischemia and low digital brachial indices (<60%) and were divided into a mild (Grade I-IIa) and a severe hemodialysis access-induced distal ischemia (IIb-IV) group. The control group consisted of hemodialysis patients without signs of hemodialysis access-induced distal ischemia with digital brachial indices ≥60%. Factors potentially related to 4-year survival were analyzed.

RESULTS

Mild hemodialysis access-induced distal ischemia-patients displayed higher digital brachial indices (n = 23, 41%, ±3) compared with severe hemodialysis access-induced distal ischemia-patients (n = 28, 24%, ±4), whereas controls had the highest values (n = 48, 80%, ±2; p < .001). A total of 44 patients (44%) died during follow-up. Digital brachial index (hazards ratio 0.989 [0.979-1.000] p = .046) was related to overall mortality following correction for presence of arterial occlusive disease (hazards ratio 2.28 [1.22-4.29], diabetes (hazards ratio 2.00 [1.07-3.72], and increasing age (hazards ratio 1.03 [1.01-1.06] as was digital pressure (hazards ratio 0.990 [0.983-0.998], p = .011). Overall survival was similar in mild hemodialysis access-induced distal ischemia and controls (2-year, 79% ±5; 4-year, 57% ±6, p = .818). In contrast, 4-year survival was >20% lower in patients with severe hemodialysis access-induced distal ischemia (2-year 62%± 10; 4-year 34% ± 10; p = .026).

CONCLUSION

Presence of severe hemodialysis access-induced distal ischemia may be associated with poorer survival in hemodialysis patients. Lower digital brachial index values are associated with higher overall mortality, even following correction for other known risk factors.

Recovery from ischemic monomelic neuropathy after delayed ligation of dialysis access

Ischemic monomelic neuropathy is characterized by acute painful muscle weakness shortly after access creation and neuronal axon loss without adjacent tissue necrosis, thus, differentiating ischemic monomelic neuropathy from the steal syndrome. Immediate ligation of vascular access is emphasized in current guidelines. We present two cases of recovery from ischemic monomelic neuropathy despite delayed ligation for over 20 days after ischemic monomelic neuropathy development. The gradual change in serial nerve conduction studies over the 15-month follow-up after surgical ligation was noted along with clinical recovery. Our report indicates that the clinical course and prognosis of ischemic monomelic neuropathy may be more diverse than previously known.

A percutaneous endovascular technique for reducing arteriovenous fistula flow

Reduction of arteriovenous access flow is usually performed by tightening the inflow lumen through an open surgical procedure. A percutaneous endovascular approach can provide a precise and effective reduction of access flow without making a skin incision. After placing a vascular introducer sheath toward the inflow direction of an arteriovenous fistula, a small stent (5 mm diameter × 25 mm length) was deployed in the target area near the anastomosis. A second stent (10 mm × 60 mm) was then deployed inside the first stent, making a corset-shape constraint on the access flow. This newly described endovascular procedure was utilized to reduce the excessive flow of arteriovenous fistula in three patients. Deployment of the constrained stent-graft resulted in reducing the estimated access flow from 1900, 1600, and 1500 mL/min to 1100, 900, and 900 mL/min, respectively. Percutaneous endovascular placement of a constrained stent-graft can narrow the inflow lumen of arteriovenous access to a desired precise diameter of 5 mm and effectively reduce access flow over a long-term period.

Ultrasound in dialysis access: Opportunities and challenges

Sonography is increasingly being used by nephrologists and the field of dialysis access is no exception. Advances in technology have allowed the addition of this universally available, portable, non-invasive tool to the nephrologist's armamentarium, which provides information on both morphology and physiology without the need for contrast or radiation. Ultrasound may be used across the spectrum of dialysis access, including central venous catheter placements, vascular mapping, regional anesthesia, creation, maintenance and assessment of hemodialysis access as well as assessment of the abdominal wall and peritoneal dialysis catheter placements. However, the lack of exposure in most training programs limits incorporation of routine use of ultrasounds in nephrology practice. As our specialty embarks on the ultrasound revolution, a two-pronged approach is essential to provide ample training opportunities while ensuring establishment of basic standards for training and competency.

Upper extremity arterial endovascular interventions for symptomatic vascular access-induced steal syndrome

BACKGROUND

Critical hand ischemia owing to vascular access-induced steal syndrome (VASS) continues to be a significant problem. The aim of this study was to examine the outcomes of arterial endovascular interventions in the upper extremity of patients presenting with VASS.

METHODS

A database of patients presenting with documented VASS between 2006 and 2016 was retrospectively queried. Patients who underwent isolated endovascular intervention in the upper extremity were analyzed.

RESULTS

Ninety-eight patients (66% female; average age 65 years) presented with VASS: 28 presented with upper arm atherosclerotic disease above the arteriovenous (AV) anastomosis (above elbow) and the remaining 70 patients with below AV anastomotic atherosclerotic disease at the elbow (below elbow). Sixty-three percent of the entire patient cohort (N = 65) presented with rest pain and the remainder (n = 33 [34%]) with minor digital ulceration. Of those with upper arm disease above the AV anastomosis, one-third of patients had subclavian occlusive disease and two-thirds had brachial artery occlusive disease. Patients with subclavian disease underwent stent placement, and patients with brachial artery disease underwent balloon angioplasty. Technical success was 100% (n = 28). Ninety-one percent of these patients (n = 25) had symptomatic success at 30 days and the remainder (n = 3) required proximalization of the access. Of those with below AV anastomosis at the elbow disease, all had disease in the forearm vessels with 42% (n = 29) having either the ulnar or radial artery occlusion. Balloon angioplasty was performed in one vessel in 55% (n = 38) and in two vessels in 45% (n = 32) of patients. Technical success was 79% (n = 81 of 102 vessels) with 51% of the patients (n = 36) having symptomatic success at 30 days; of those who remained symptomatic, 80% (n = 27) required proximalization of the access and 20% (n = 7) required ligation. The major adverse cardiovascular event rate for the entire patient cohort was 4% (n = 4). The 30-day complications for the entire patient cohort included continued steal (38%; all resolved with secondary procedures), thrombosis (3%; all forearm vessels treated for occlusion), bleeding (0%), infection (0%), and mortality (1%). Primary clinical success defined as the relief of distal ischemic symptoms and the preservation of a functional access site for dialysis showed rates of 42 ± 9% (mean ± standard error of the mean) and 0 ± 0% at 5 years (above and below elbow groups, respectively).

CONCLUSIONS

Upper extremity interventions for VASS owing to above elbow disease are associated with a high rate of success, whereas interventions for below elbow disease have a poor clinical success with more patients requiring secondary procedures and low long-term survival for the access site. Male patients presenting with rest pain, larger forearm vessels (approximately 3 mm), short occlusive lesions (<100 mm), two-vessel runoff, and an intact palmer arch are good candidates for below elbow interventions.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

The sleeve method for creation of radiocephalic arteriovenous fistulas in patients with calcified vessels

INTRODUCTION

Creation of an arteriovenous fistula (AVF) in patients with advanced atherosclerotic changes of the artery is often a challenge for the physician due to difficulties in suturing the vein to the side of the frangible artery. The sleeve technique relies on advancing the end of the artery into the lumen of the vein and protecting the anastomosis by adventitial sutures.

MATERIAL AND METHODS

The sleeve technique was performed in 23 patients with chronic kidney disease stage IV and V and included hemodialysis patients. Their mean age was 60.8 ± 14.8 years and hemodialysis treatment time 49.8 ± 40.2 months. The most frequent causes of chronic kidney disease are ischemic nephropathy (43%, n = 10) and type l diabetes (21%, n = 5). Only patients with extremely advanced atherosclerotic were recruited and analyzed.

RESULTS

The primary patency rate was 67%, 59%, 44% and 28% at 6, 12, 24, and 36 months, respectively. The secondary patency rate was 67%, 61%, 50% and 37% at 6, 12, 24, and 36 months, respectively. In three patients the AVF failed directly after the operation. Delayed fistula failure occurred in seven patients. The overall success in the creation of a functioning fistula was achieved in 15 of the 23 patients (65%). No serious complications were observed.

CONCLUSIONS

In patients with calcified atherosclerotic plaques, which constitute a barrier or make it difficult to suture the vein to the side of the artery, the sleeve method may be considered as an alternative before abandoning the creation of a fistula on the forearm. The technique is much simpler than the standard end-to-side or side-to-side anastomosis.

[Vascular steal syndrome due to the creation of an arteriovenous shunt for hemodialysis, patient information and nephrologist responsibility]

Although responsibility is a fundamental determinant in medical practice, physicians are generally unfamiliar with its principles. The same is true for disclosure requirements and requests for compensation in the event of physical injury. We report on a representative survey of iatrogenic complications that may arise after the implementation of vascular access for haemodialysis and that illustrate's the physician's responsibility and obligation to inform the patient. Vascular access steal syndrome is a serious complication of arteriovenous fistulas, and physicians may not be sufficiently aware of the likelihood of its occurrence. Diabetes (via medial calcific sclerosis) and placement in the brachial artery (with excessively high flow rates) are the main risk factors. The precariousness of vascular status in dialysis patients threatens to increase the incidence of this complication. The therapeutic challenge is to resolve ischemic events while maintaining vascular access. The presence of gangrene of the fingers is a formal indication for surgery. The borderline between therapeutic risk (the risk inherent in a medical procedure and which cannot be controlled) and liability for injury is blurred. The French Patient's Rights Act (voted on March 4th, 2002) emphasizes the physician's duty to inform the patient of treatment-associated risks and the fact that the physician now bears the burden of proof. We suggest that a patient information sheet on the benefits and risks of vascular access should be published on the French Society of Nephrology, Dialysis and Transplantation's website.

Dialysis-associated steal syndrome (DASS)

INTRODUCTION

In this article, we will review the clinical symptoms of dialysis access steal syndrome (DASS), evaluation, treatment options, and our approach and treatment algorithm.

METHODS

We reviewed the literature discussing different aspects of DASS including its epidemiology, pathogenesis, clinical presentation, evaluation and management options.

RESULTS

DASS is the most dreaded complication of access surgery. Although the incidence is low, all providers caring for dialysis patients should be aware of this problem. Symptoms can range from mild to limb threatening. Although various tests are available, the diagnosis of DASS remains a clinical one and requires thoughtful management to have the best outcomes.

CONCLUSIONS

Multiple treatment options exist for steal. We present diagnostic evaluation and management algorithm.

Arteriovenous Vascular Access Selection and Evaluation

When making decisions regarding vascular access creation, the clinician and vascular access team must evaluate each patient individually with consideration of life expectancy, timelines for dialysis start, risks and benefits of access creation, referral wait times, as well as the risk for access complications. The role of the multidisciplinary team in facilitating access choice is reviewed, as well as the clinical evaluation of the patient.

Dilator-assisted Banding and Beyond: Proposing an Algorithm for Managing Dialysis Access-associated Steal Syndrome

Purpose

Dialysis access-associated steal syndrome (DASS) is a major complication of arteriovenous hemodialysis accesses. Although its underlying pathology is diverse, it is most often associated with excessive access flow. Dilator-assisted banding (DAB) is a simple flow-reduction technique that we described previously. This report is to illustrate the expansion of DAB and analyze the outcome of DAB in managing DASS.

Methods

From February 2011 to April 2015, 30 patients underwent DAB for DASS. Their relevant clinical data were retrospectively reviewed or prospectively collected, and further analyzed statistically.

Results

Of the 30 patients, 23 had an arteriogram and 3 required angioplasty ± stent placement for inflow artery stenosis. Besides intraluminal DAB (12/30), this report also included extraluminal DAB (14/30) and open fistula reduction plus DAB (4/30). After DAB, the severity scores of DASS were reduced from 2.8 ± 0.4 to 0.2 ± 0.4 for the fistula group (n = 24, p<0.001) and from 3.0 ± 0.0 to 1.2 ± 1.2 for the graft group (n = 6, p = 0.041). DAB was effective in all but two graft patients who subsequently underwent proximalization of arterial inflow (PAI) that resulted in resolution of DASS. During follow-up of 18.7 ± 14.5 months (range 1-50), all accesses remained functional. At 24-months post-DAB, the primary patency, primary-assisted patency and secondary patency rates of the fistula group were 72%, 91% and 100%, respectively.

Conclusions

DAB is a simple, effective and versatile approach for managing DASS. PAI may be employed for rescue or as primary choice when banding is ineffective. Based on our data and the literature, an algorithm is proposed for managing DASS.

The MILLER banding procedure as a treatment alternative for dialysis access steal syndrome: a single institutional experience

OBJECTIVE

To describe a single institutional experience with minimally invasive limited ligation endoluminal-assisted revision (MILLER) for treatment of dialysis access steal syndrome (DASS).

MATERIALS AND METHODS

Twenty patients were retrospectively identified that underwent 30 MILLER band procedures for DASS at our institution from March 2010 to December 2014. Technical success was defined by successful creation of MILLER band with preservation of flow for hemodialysis. Clinical success was defined as complete resolution of signs and symptoms with preservation of dialysis access in a 1-month postprocedural period. Primary MILLER band patency, postintervention-assisted primary access patency, and postprocedure secondary access patency are reported.

RESULTS

Technical success was achieved in all patients. Clinical success was achieved in 75% of patients after one banding procedure and in 95% of patients after two banding procedures. One patient experienced access thrombosis following the initial banding procedure which was subsequently treated and did not lead to loss of access. MILLER band patency was 83% at 1 month and 77% at 6 months. Postintervention-assisted primary patency was 95%, 93%, and 92% at 3 months, 6 months, and 1 year, respectively. Postintervention secondary patency was 86%, 68%, and 59% at 3 months, 6 months, and 1 year, respectively.

CONCLUSIONS

MILLER banding offers a less-invasive alternative to surgical therapy that appears to be safe and permits preservation of dialysis access.

One-Year Efficacy of the RUDI Technique for Flow Reduction in High-Flow Autologous Brachial Artery-Based Hemodialysis Vascular Access

Purpose

Flow reduction is advised in hemodialysis (HD) patients with a high-flow (>2 L/min) arteriovenous fistula (AVF). The revision using distal inflow (RUDI) technique is based on the premise that access flow is attenuated once inflow is provided by a smaller caliber forearm artery. Aim of the study was to evaluate the efficacy of RUDI during a 1-year follow-up.

Methods

All HD patients undergoing a RUDI operation using a greater saphenous vein (GSV) or a basilic vein (BaV) interposition for a high-flow access (HFA, >2 L/min) during a 3.5-year time period were included. Serial access flow, percentage of freedom from recurrent high flow and complications were determined.

Results

A total of 19 HFA patients were studied (11 males, age 55 ± 3 years). All AVFs were brachial artery based (brachiocephalic, n = 14; brachiobasilic, n = 5). RUDI immediately reduced access flow by almost 2 L/min (3,080 ± 200 to 1,170 ± 160 mL/min (p = 0.001)). Access flows at 1, 6 and 12 months were 1,150 ± 160, 1,460 ± 200 and 1,580 ± 260 mL/min, respectively. Postoperative complications included insufficient flow reduction (n = 1, BaV) and occlusion requiring revision (n = 1, GSV). Recurrent HFA occurred three times (n = 2 BaV, n = 1 GSV). Access flows were significantly (p<0.05) higher in the BaV group compared to the GSV group.

Conclusions

RUDI effectively reduces access flow in a brachial artery-based high-flow HD vascular access. A flow-reducing effect is sustained at 1-year follow-up in most patients. GSV is preferred as an interposition graft compared to a BaV.

Alternative prosthetic vascular access creation using subscapular artery as inflow to prevent dialysis access related steal syndrome

In patients highly suspected of developing steal syndrome, the subscapular artery may be a good supplier for functional prosthetic arteriovenous access, as well as a good solution for the prevention of steal syndrome. A 51-year-old woman was preparing to have a loop shaped polytetrafluoroethylene (PTFE) graft placed at the left upper extremity. The diameter of subscapular the artery was 3 mm. Arterial calcification was not evident. The diameter of the basilic vein was 6 mm. A 50-cm long 4-7 mm tapered PTFE graft was placed in a loop shape between both skin incisions. The patient was uneventfully discharged at postoperative day 4 without any remaining steal syndrome. The PTFE graft was well-functioning during the follow-up period. The patient did not experience symptoms of steal syndrome any longer.

Surgical Techniques for Haemodialysis Access-Induced Distal Ischaemia

Purpose

Haemodialysis access-induced distal ischaemia (HAIDI) is a significant complication of vascular access creation, and has traditionally been difficult to manage without loss of access. Current treatment options include ligation, banding, distal revascularisation with interval ligation (DRIL), proximalisation of the arterial inflow (PAI) and revision using distal flow (RUDI). The purpose of this review was to evaluate the effectiveness of the different surgical techniques in the treatment of HAIDI.

Methods

Electronic databases were searched for studies assessing surgical techniques in the treatment of HAIDI in accordance with PRISMA. The primary outcome for the study was symptomatic relief for each technique, defined within each study. Secondary outcomes included comparison of early thrombosis rates following each different procedure.

Results

Following strict inclusion/exclusion criteria by two reviewers, twenty-seven studies of surgical interventions were included and divided into subgroups for banding, DRIL, PAI and RUDI procedures. Both DRIL and banding procedures were found to have high rates of symptomatic relief. In addition, the DRIL has a significantly lower rate of early thrombosis than banding although the more recent papers seem to suggest that early thrombosis is less of a problem in banding. PAI and RUDI showed some promise but there were too few studies to be able to make any clear conclusions.

Conclusions

All four procedures have high success rate in relieving ischaemic symptoms with the DRIL procedure having a significantly better vascular access patency rate than other techniques, although further well designed studies are required to compare all four surgical techniques.

Preoperative Duplex Examination in Patients with Dialysis Access-related Hand Ischemia: Indication for Distal Radial Artery Ligation

Purpose

To demonstrate that treatment with distal radial artery ligation (DRAL), based on preoperative evaluation with duplex ultrasound, is effective for correction of hand ischemia related to distal radiocephalic arteriovenous fistula (AVF).

Methods

Two patients with symptoms of hemodialysis access-induced distal ischemia (HAIDI) related to radiocephalic AVF at wrist (necrotic lesion of fingers, pain at rest and loss of sensory function) were studied with preoperative duplex examination. Color Doppler ultrasound (CDU) showed low-normal flux (700 and 500 mL/min respectively), retrograde flow in the DRA and increased digital perfusion after manual occlusion of DRA. They were both treated by ligation of the DRA.

Results

Both patients had immediate improvement of ischemic symptoms. Reversed DRA flow disappeared and peripheral flow ameliorated. Postoperative AVF flow was 500 and 350 mL/min, stable at 16 and 8 months of follow-up, respectively.

Conclusions

Preoperative CDU examination, simulating reversed DRA flow interruption, seems to be an effective tool to predict the success of DRAL procedure.

Clinical outcomes after arteriovenous fistula creation in chronic kidney disease

BACKGROUND

Optimal timing of arteriovenous fistula (AVF) surgery in chronic kidney disease (CKD) is uncertain.

METHODS

A single-centre retrospective study of pre-dialysis CKD patients having first AVF surgery.

RESULTS

The median estimated glomerular filtration rate (eGFR) at the time of AVF surgery in 100 patients was 15 ml/min/1.73 m(2), with patients classified as having an early AVF if eGFR was >15 ml/min/1.73 m(2) (n = 46) or a late AVF if eGFR was ≤15 ml/min/1.73 m(2) (n = 54). In the eGFR ≤15 group, 81% of patients started haemodialysis (HD), compared with 63% of the eGFR >15 patients (p = 0.04). The median time to starting HD was 30.3 months in the eGFR >15 group compared to 10.7 months for the eGFR ≤15 group (log rank p = 0.018). There were no differences in the requirements for a dialysis catheter (eGFR >15 24% vs. eGFR ≤15 11%, p = 0.20) or additional access procedures between the two groups.

CONCLUSIONS

AVF surgery with an eGFR >15 ml/min/1.73 m(2) was associated with a higher risk of AVF non-use and a more prolonged time to the need for HD.

Chronic Hemodialysis Access-Induced Distal Ischemia (HAIDI): Distinctive form of a Major Complication

Purpose

Hemodialysis access-induced distal ischemia (HAIDI) is an uncommon but potentially devastating complication. HAIDI is classified as acute, subacute and chronic based upon the time of onset. The aim of this study was to determine the prevalence, severity, patients’ characteristics and the underlying etiologic mechanism of chronic HAIDI using color Doppler ultrasonography (CDUS).

Methods

Between June and August 2010, 676 hemodialysis patients with arteriovenous access (AVA) were evaluated for clinical evidence of chronic HAIDI. In the case–control part of the study, CDUS findings were compared between ischemic patients and asymptomatic matched controls. Also, patients with chronic HAIDI were followed up until February 2014, access ligation, kidney transplantation or death.

Results

Eighteen chronic HAIDI patients were diagnosed (2.66%). Cold hand and cold sensation were the most common signs and symptoms of hand ischemia, respectively. Fifteen patients were classified in stage 1. Patients with proximal autogenous arteriovenous fistula, younger age, more previous AVAs and less access age were more likely to develop chronic HAIDI. Excessive fistula flow was found in the majority of ischemic patients (83.3%). The mean fistula flow was significantly higher in cases compared to controls (p=0.001). Eleven patients with chronic HAIDI were successfully treated by conservative measures alone until the end of follow-up ( n=3), kidney trans-plantation ( n=4) or death ( n=4).

Conclusions

CDUS is a useful adjunctive diagnostic tool to determine the etiology of chronic HAIDI. Conservative measures combined with close follow-up can be used as the first step in the management of chronic HAIDI patients with mild symptoms.