Editor's Choice – Vascular Access: 2018 Clinical Practice Guidelines of the European Society for Vascular Surgery (ESVS)

Hand Acceleration Time is a Valuable Ultrasonographic Tool in Hand Perfusion as Adjuvant Evaluation for Diagnosing Chronic Upper Limb Ischemia

BACKGROUND

Diagnosis of chronic upper limb ischemia is mainly clinical. Although hand perfusion can be evaluated by different noninvasive methods (e.g., digital-brachial index, digital pressures, oxygen saturation measurements, and plethysmography), these have not been standardized for the diagnosis of chronic upper limb ischemia. Initial reports suggested that the hand acceleration time (HAT) measured by duplex ultrasound could be a useful diagnostic tool. However, the HAT has neither been properly characterized nor validated. This study aimed to provide evidence that HAT is a sensitive diagnostic tool for chronic upper limb ischemia.

METHODS

We conducted a prospective, single-center, cross-sectional study with adult patients diagnosed with chronic upper limb ischemia and healthy adult volunteers without cardiovascular risk factors. Hand vascular duplex ultrasound and HAT measurement were performed in 4 artery locations: princeps pollicis artery, radialis indicis artery, first common digital palmar artery, and third common digital palmar artery. It was also measured in the ulnar and radial arteries. Descriptive and exploratory analyses were performed between patients and healthy volunteers.

RESULTS

Thirty participants were included, being 15 patients (median [standard deviation] age: 51 [18] years; 47% women) and 15 healthy volunteers (median [standard deviation] age: 35 [10] years; 60% women). In total, 15 ischemic and 30 nonischemic hands were analyzed. Humeral artery stenosis/occlusion (n = 6, 40.0%) and distal artery stenosis (n = 5, 33.3%) were the main causes of ischemia. Median (interquartile range) HAT measurements were significantly different between patients and healthy volunteers in the 4 hand arterial locations, the radial artery, and ulnar artery: princeps pollicis artery: 164 (124-252) vs. 60 (40-88), P < 0.001; radialis indicis artery: 176 (140-348) vs. 60 (36-80), P < 0.001; first common digital palmar artery: 180 (92-320) vs. 64 (36-88), P < 0.001; third common digital palmar artery: 180 (104-240) vs. 56 (44-92), P < 0.001; radial artery: 156 (120-248) vs. 68 (55-76), P < 0.001; and ulnar artery: 152 (76-220) vs. 61 (48-76), P < 0.001.

CONCLUSIONS

Vascular duplex ultrasound with HAT measurement seems to be an easy-access, sensitive diagnostic tool for chronic upper limb ischemia. HAT provides valuable information on hand perfusion and may be complementary to current noninvasive methods.

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.

Unplanned hemodialysis initiation: A retrospective analysis of patient characteristics and prognosis in an emergency hospital

INTRODUCTION

Functional decline occurs during dialysis initiation, particularly in unplanned cases. To prevent unplanned hemodialysis, we aimed to identify associated factors from the first referral to the nephrology department to hemodialysis initiation and assess patient prognosis post-unplanned hemodialysis initiation.

METHODS

This retrospective study involved 257 Japanese patients initiating hemodialysis and compared patient characteristics based on whether hemodialysis was planned or unplanned at a single center. Patient outcomes were evaluated in collaboration with maintenance hemodialysis centers.

RESULTS

Unplanned hemodialysis initiation correlated with heart failure history (p < 0.05) and infections like pneumonia (p < 0.001). Patients with unplanned hemodialysis initiation had a worse prognosis than those with planned initiation (p < 0.001), and multivariable Cox regression showed it as an independent risk factor for death (p < 0.05).

CONCLUSIONS

Hygiene and careful attention to heart failure may reduce unplanned hemodialysis and improve patient well-being and healthcare efficiency. This retrospective analysis highlights crucial considerations for optimizing the initiation of hemodialysis.

Early postoperative resistance index can predict radiocephalic arteriovenous fistula failure

BACKGROUND

Ultrasonography is valuable for assessing arteriovenous fistula (AVF) maturation. Brachial artery flow volume (FV) measured at 6 weeks post-AVF creation can predict AVF failure. However, the association between early postoperative FV and AVF failure remains unclear. The resistance index (RI) may also serve as a prognostic factor for AVF maturation; however, it has not been extensively studied. Therefore, we aimed to investigate the relationship between AVF failure and early postoperative FV and RI.

METHODS

We retrospectively analyzed data from 102 patients (mean age, 67.8 ± 14.2 years; male, 68.6%; diabetes mellitus, 52.0%) who underwent new radiocephalic-AVF creation between January 2019 and December 2023 in Japan. An ultrasound device was used to measure brachial artery FV and RI on postoperative days 0 and 1. AVF failure was defined as occlusion or stenosis requiring vascular access intervention or surgical revision before the first cannulation, or cannulation difficulty or FV dysfunction requiring vascular access intervention or surgery at the first cannulation.

RESULTS

On postoperative day 0, FV was 383.1 ± 146.8 mL/min, and RI was 0.65 ± 0.11. On postoperative day 1, FV was 466.9 ± 179.2 mL/min, and RI was 0.62 ± 0.11. FV significantly increased, and RI was significantly reduced on postoperative day 1 compared to those on day 0 (p < 0.01). Multivariate analyses revealed that higher RI (per 0.1; odds ratio (OR), 2.16; 95% confidence interval (CI), 1.22-3.82), but not FV, was significantly associated with AVF failure on postoperative day 0. On postoperative day 1, lower FV (per 100 mL/min; OR, 0.63; 95% CI, 0.42-0.95) and higher RI (per 0.1; OR, 2.17; 95% CI, 1.16-4.05) were significantly associated with AVF failure.

CONCLUSIONS

This study highlights RI as a predictor of AVF failure in the early postoperative period when vasospasm is likely to occur.

Features associated with arteriovenous fistula patency. A meta-analysis

INTRODUCTION

It is unclear if cannulation-associated variables such as timing of first cannulation, access creation method, cannulation technique, or needle type are associated with the outcomes of arteriovenous fistulas. We conducted a meta-analysis to investigate such potential associations with 1-year primary patency.

METHODS

Twenty-eight publications with titles that included "arteriovenous fistula," "patency," "cannulation," "metric," "first cannulation," "hemodialysis," "complication," "vascular," "nursing," and "puncture" were retrieved and reviewed.

FINDINGS

The 1-year primary patency rates ranged from 0.32 to 0.93. Primary patency rates were significantly lower in patients in whom initial cannulation was done less than 1.5 months after fistula creation compared to fistulas first cannulated more than 1.5 months after anastomosis (odds ratio [OR] = 0.41, 95% confidence interval [CI]: 0.32-0.52). The effect of cannulation timing on primary patency rate was attenuated when plastic cannulas were used during the first two to three puncture weeks compared to metal needles (OR = 0.62 vs. 0.34; p = 0.032). Fistulas in the upper arm did not have a higher 1-year primary patency compared to those in the forearm (OR = 1.05, 95% CI: 0.93-1.19). Primary patency of upper arm arteriovenous fistulas was higher in reports from the Americas or Europe compared to reports from Asia. Buttonhole cannulation was not associated with higher patency rates at 1 year compared to rope-ladder cannulation (OR = 1.14, 95% CI: 0.75-1.71).

DISCUSSION

Early cannulation was associated with reduced 1-year arteriovenous fistula patency. This association was reduced when plastic cannulas were used during the initial 2-3 weeks.

Comparative study between the halfway technique and the standard technique for exchange of tunneled hemodialysis catheter

OBJECTIVES

When indicated, tunneled hemodialysis catheters are usually inserted using the standard technique but, this technique has its complications. The halfway method is performed by exchange of an already-inserted dialysis catheter (tunneled or non-tunneled) to a tunneled one over a guidewire mounted via the old catheter. In this study, we aimed at evaluating the feasibility, safety, and durability of halfway method in comparison to the standard technique (de novo puncture).

PATIENTS AND METHODS

This prospective study was conducted during the period from May 2020 till May 2022 and included 87 patients with end-stage renal disease (ESRD) on regular hemodialysis (HD) in need for insertion new tunneled dialysis catheters instead of temporary or malfunctioning tunneled ones. According to the technique of catheter insertion, these patients were divided into two groups: group A (the halfway technique: catheters were exchanged over guidewires under fluoroscopic control; 48 patients) and group B (the standard technique: via de novo ultrasound-guided vein puncture; 39 patients). Instant, delayed complications and 12-months patency rates were reported and analyzed.

RESULTS

The frequency of peri-operative bleeding complications was better in the halfway group with comparable infection rate and late catheter dysfunction results between the two groups. One year patency rates were 87.5% in halfway technique group compared to 79.5% in standard technique group, yet without statistical significance. However, there was a statistically significant shorter operative time in halfway group (15.54 ± 2.6 min vs 26.97 ± 5.6 min, p < 0.001).

CONCLUSION

The halfway technique may be recommended over the standard technique of tunneled catheter insertion due to shorter operative time, lower rate of hematoma formation, with non-inferior 1-year patency rates and comparable technical success and infection rates. The advantage of access sites preservation for future demand makes this technique of great value to this group of ESRD patients.

Streamlining Preoperative Evaluation for Dialysis Access: A Pilot Study

BACKGROUND

Outpatient in-person clinic evaluation is the standard consultation practice for an initial referral for hemodialysis (HD) access. However, most factors predicting the complexity of first-time access surgery can be determined from history rather than physical exam. This study compares the outcomes of patients undergoing first-time arteriovenous fistula creation screened with a standardized preoperative phone interview and no preoperative clinic visit (SPEEDY group) to those opting for a standard in-person clinic visit.

METHODS

From September 2021 to August 2022, all patients scheduled in our vascular surgery clinic for first-time dialysis access were interviewed via telephone using a standardized history questionnaire. Those meeting criteria and expressing desire to bypass the initial clinic visit were scheduled for surgery without an in-person preoperative evaluation (SPEEDY group). The comparison group included patients who were study-eligible but desired to meet with the surgeon preoperatively. Time from referral to fistula creation, overall fistula patency rates, and the incidence of access-specific complications were compared between the 2 groups.

RESULTS

Of the 107 patients contacted, 43 (40%) were study eligible. Of these eligible patients, 21 (49%) were scheduled for surgery without a preoperative visit, of whom 19 (90%) underwent surgery. Compared to eligible controls, SPEEDY patients had a younger median age (49.3 years vs. 58.9, P = 0.056) but similar median duration of HD prior to fistula creation. SPEEDY patients had a significantly shorter median time from initial referral to surgery than eligible controls (48 days vs. 82, P = 0.01). Incidence of complications did not differ between the groups. At a median follow up time of 18.3 months (IQR 11.4-20.9) there was no difference in overall access patency between SPEEDY participants and eligible controls (P = 0.83).

CONCLUSIONS

A standardized telephone questionnaire can effectively be used to identify patients who can safely undergo first time dialysis access surgery without an in-person clinic evaluation, significantly reducing time from initial referral to surgery without increasing complications or compromising patency rates.

Evaluation of the relationship between proximal upper-extremity arteriovenous fistula patency and atherogenic index of plasma

BACKGROUND

The continuity of arteriovenous fistula (AVF) patency is essential for effective hemodialysis. In the present study, we aimed to investigate the relationship between AVF patency and atherogenic index of plasma (AIP) in patients with native proximal upper-extremity AVF.

METHODS

A total of 143 patients with native proximal upper-extremity AVF created in our clinic between January 2014 and April 2022 were analyzed retrospectively. Those with at least 24 months of follow-up and intact AVF were defined as "Group 1" (n = 97), and those with AVF thrombosis were defined as "Group 2" (n = 46).

RESULTS

The primary patency rates of the patient groups included in the study were found to be 88.1% at 6th month, 79% at 12th month, and 67.8% at 24th month. The mean AIP values that were calculated in Group 2 were found to be statistically significantly higher than the mean value calculated in Group 1 (0.30 ± 0.12 vs 0.20 ± 0.10, p < 0.001). In a multivariate logistic regression analysis made to identify the predictors of proximal upper-extremity AVF thrombosis development, total cholesterol (OR [odds ratio] = 2.259, 95% CI [confidence interval] = 1.468-3.475, p < 0.001), and triglyceride (OR = 13.777, 95% CI = 3.740-50.750, p < 0.001) were identified as independent predictors.

CONCLUSION

A significant relationship was detected in the analyses between the easily calculated AIP values and the development of AVF thrombosis. The AIP is a remarkable preoperative parameter regarding proximal upper-extremity AVF patency.

Collapse of a cephalic arch stent: An atypical complication of hemodialysis vascular access

Access dysfunction is a significant contributor to morbidity in hemodialysis patients. The cephalic arch is a common location of vascular stenosis, with a considerable risk of relapse. While covered stents demonstrated a higher patency rate when compared to percutaneous transluminal angioplasty, their placement has some issues. Stent collapse and guttering are well-documented in arteries but not in arteriovenous fistulas. This report describes an unusual case of a cephalic arch stent collapsing 1 month after its positioning, as evidenced by access dysfunction.

Prognostic nomogram for the patency of wrist autologous arteriovenous fistula in first year

Autologous arteriovenous fistula (AVF) is preferred in hemodialysis patients. Maintaining its patency is a critical problem. This study aimed to create a nomogram model for predicting 1-year primary patency of AVF. Consequently, a total of 414 patients were retrospectively enrolled and randomly allocated to training and validation cohorts. Risk factors were identified by multivariable logistic regression and used to create a nomogram model. Performance of the model was evaluated by receiver operating characteristic (ROC) curve, Hosmer-Lemeshow test, and calibration curve. The results suggested that diameter of cephalic vein, low-density lipoprotein, glycosylated hemoglobin (%), and C-reactive protein were risk factors which could predict the patency of AVF. Area under ROC curves for training and validation cohorts were 0.771 and 0.794, respectively. Calibration ability was satisfactory in both cohorts. Therefore, present nomogram model could predict the 1-year primary patency of AVF.

Perioperative Vascular Access Mapping in Patients with Hemodialysis: A Comparative Study of Access Navigation and Selection in Jordan

Purpose

This study aimed to elucidate the impact of three different mapping methods on the outcomes of arteriovenous fistula (AVF), including the traditional physical examination (PE) method, color duplex ultrasonography (CDU) mapping conducted by a radiologist (CDU-R), and CDU mapping performed by the operating surgeon (CDU-S).

Patients and Methods

This retrospective study was conducted at a tertiary center in Jordan. Patients were divided into three groups based on the venous mapping method: PE, CDU-R, and CDU-S. Various outcomes were analyzed, including immediate technical success, clinical adequacy at 3 months, and 1-year patency rates. Additional demographic and clinical factors influencing access patency or contributing to early failure were also examined.

Results

The study included 303 eligible patients: 100 in the PE group, 103 in the CDU-R group, and 100 in the CDU-S group. The overall immediate technical success rate was 72%, which was highest in the CDU-S group (95%, p < 0.001). Additionally, the CDU-S group had the highest clinical access adequacy rate (78%, p < 0.01). Notably, the mapping method also influenced the anatomical location of the AVF, as none of the patients in the radiologist group had a forearm AVF. CDU-R, forearm location, intraoperative arterial calcifications, and operative duration were identified as predictors of AVF failure.

Conclusion

The results suggest that perioperative vascular mapping by the operating surgeon not only results in a higher rate of immediate success but also improves access adequacy and prevents unnecessary delays in providing an effective lifeline for hemodialysis patients. The present study highlights the burden of access failure in these patients and the evolving evidence surrounding preoperative vein mapping.

Impact of arteriovenous fistula aneurysms on a UK dialysis populations' perception of vascular access

BACKGROUND

Clinically-oriented outcome measures are increasingly being recognized as lacking in consideration of factors important to patients. There is an emerging move of guideline bodies advocating a more patient-centred approach. Aneurysms in autogenous arteriovenous fistula (AVF) can be considered unsightly and a constant reminder for patients of their dependence on dialysis. However, their impact on patient's perception has not previously been reported.

METHODS

Between April 2017-18, the Vascular Access Questionnaire (VAQ) was administered to prevalent haemodialysis patients across ten dialysis units via structured interviews, as part of a quality improvement project. Data for the subgroup of patients with aneurysmal AVF (categorised as per classification by Valenti et al.), were retrospectively evaluated and compared to the wider cohort.

RESULTS

Data were collected for 539 patients (median age: 66 years; 59% male), of whom 195 (36%) had aneurysmal AVF, with Type 2 morphology (cannulation site) being the most common (75%). Duration of AVF was found to be significantly associated with aneurysmal development, with estimated likelihoods of 11%, 43% and 61% after one, five and ten years, respectively. Interestingly, patients with diabetes had a significantly lower prevalence of aneurysmal development than those that were non-diabetic (25% vs. 43%, p < 0.001). Overall VAQ scores were not found to differ significantly by aneurysm status (p = 0.816) or across morphology types (p = 0.277). However, patients with aneurysmal AVF were significantly more concerned with the appearance of their AVF (p < 0.001) than the wider cohort. Despite this, patients with aneurysmal AVF gave significantly higher scores for satisfaction and ease of use and lower scores for bruising and clotting (p < 0.05).

CONCLUSIONS

Aneurysmal AVF are often cited as an important factor by patients for not proceeding with fistula formation. In this evaluation of patient reported experiences, those with aneurysmal AVF reported high satisfaction levels. This may help clinicians highlight positive patient reported outcomes of aneurysmal AVF during preprocedural consent processes.

Frequent use of percutaneous transluminal angioplasty is not associated with reduced vascular access recreation in a longitudinal ecology study

The frequency of percutaneous transluminal angioplasty (PTA) procedures has substantially increased, but its effect on vascular access recreation (VAR) remains inconclusive. We conducted a population-based retrospective analysis of Taiwan hemodialysis (HD) centers from 2004 to 2012. Data was accumulated into center-level characteristics, including patients' demographics, baseline characteristics, PTA procedures, and VAR. Center-level characteristics were summarized annually using appropriate measures. A mixed model assessed the association between PTA frequency and VAR rates, considering within-center correlation and adjusting for potential confounders. A total of 82,005 patients (mean age 62.7 ± 13.9 years, 50.5% male, 48.5% with diabetes mellitus) from 820 HD centers were analyzed. From 2004 to 2012, PTA frequency significantly increased from 1.24 to 3.23 per 1000 HD sessions, while VAR rates did not decline as expected (0.5-0.8 per 1000 HD sessions). Compared with the HD centers of infrequent use of PTA (annual lowest quartile, range 0.39-1.20 per 1000 HD sessions), the ones of frequent use (annual highest quartile, range 2.52-5.10 per 1000 HD sessions) didn't have lower VAR (range 0.54-0.99 vs. 0.50-0.91 per 1000 HD sessions, respectively). After controlling the potential confounders, the HD centers' PTA rates were not significantly associated with lower VAR rates (- 2.6, 95% confidence interval: - 30.3; 25.0, p = 0.85). Frequent use of PTA does not seem to improve VA patency at the center level, with no significant association identified with lower VAR. The indication of PTA in daily practice should be re-evaluated in terms of its efficiency in lowering VAR.

Proximalization of Arterial Inflow for the Treatment of Limb Ischemia in a Transposed Femoral Arteriovenous Fistula-A Case Report

INTRODUCTION

Femoral vein transposition is one of the final resorts for vascular access in patients with exhaustion of upper limb venous patrimony and central venous occlusive disease. Its major pitfalls include hemodialysis access-induced distal ischemia and infection. Surgical procedures may be warranted to preserve vascular access if ischemia develops. Several techniques are reported in the literature for femoral vein transposition.

CASE REPORT

We expose an endoscopic femoral vein harvesting as an alternative to the single thigh incision in order to avoid its associated complications. In the setting of ischemia, proximalization of arterial inflow was used to manage femoral vein transposition associated limb ischemia.

CONCLUSION

This case report aims to expose the aforementioned unreported surgical techniques for lower limb arteriovenous fistula, its advantages, and pitfalls, as well as considerations on its future use.

Guideline recommendations on minimal blood vessel diameters and arteriovenous fistula outcomes

OBJECTIVE

Clinical guidelines provide recommendations on the minimal blood vessel diameters required for arteriovenous fistula creation but the evidence for these recommendations is limited. We compared vascular access outcomes of fistulas created in agreement with the ESVS Clinical Practice Guidelines (i.e. arteries and veins >2 mm for forearm fistulas and >3 mm for upper arm fistulas) with fistulas created outside these recommendations.

METHODS

The multicenter Shunt Simulation Study cohort contains 211 hemodialysis patients who received a first radiocephalic, brachiocephalic, or brachiobasilic fistula before publication of the ESVS Clinical Practice Guidelines. All patients had preoperative duplex ultrasound measurements according to a standardized protocol. Outcomes included duplex ultrasound findings at 6 weeks after surgery, vascular access function, and intervention rates until 1 year after surgery.

RESULTS

In 55% of patients, fistulas were created in agreement with the ESVS Clinical Practice Guidelines recommendations on minimal blood vessel diameters. Concordance with the guideline recommendations was more frequent for forearm fistulas than for upper arm fistulas (65% vs 46%, p = 0.01). In the entire cohort, agreement with the guideline recommendations was not associated with an increased proportion of functional vascular accesses (70% vs 66% for fistulas created within and outside guideline recommendations, respectively; p = 0.61) or with decreased access-related intervention rates (1.45 vs 1.68 per patient-year, p = 0.20). In forearm fistulas, however, only 52% of arteriovenous fistulas created outside these recommendations developed into a timely functional vascular access.

CONCLUSIONS

Whereas upper arm arteriovenous fistulas with preoperative blood vessel diameters <3 mm had similar vascular access function as fistulas created with larger blood vessels, forearm arteriovenous fistulas with preoperative blood vessel diameters <2 mm had poor clinical outcomes. These results support that clinical decision-making should be guided by an individual approach.

Novel insights into modifiable risk factors for arteriovenous fistula failure and the importance of CKD lipid profile: A meta-analysis

BACKGROUND

Arteriovenous fistula (AVF) failure can occur in patients undergoing hemodialysis (HD). In this study, we explored the correlation between hyperlipidemia and AVF failure in patients undergoing HD. Moreover, we compared the lipid profiles of patients with chronic kidney disease (CKD) with those of healthy people to provide a basis for lipid-lowering in patients undergoing HD.

METHOD AND ANALYSIS

We searched PubMed, Web of Science, Embase, the Cochrane library, CNKI, CBM, the China Science Periodical Database, and the China Science and Technology Journal Database. The final search was conducted on August 31, 2021, and the search period was restricted between 2000 and August 31, 2021, without publication restrictions. All studies met the inclusion criteria, and the influences of sex, age, geographical location, diagnosis method, and publication year were excluded. The data were analyzed using the random-effects model and the fixed-effects model.

RESULTS

Twenty-eight studies were included in the meta-analysis with 121,666 patients in the CKD group and 1714 patients in the AVF failure group. Triglyceride concentration in patients with CKD was higher than in healthy subjects (MD: -31.56, 95% CI: -41.23 to -21.90, p < 0.00001). A high total cholesterol (TC) concentration (MD: 6.97, 95% CI: 2.19-11.74, p = 0.004) and a high low-density lipoprotein cholesterol (LDL-C) concentration (MD: 23.83, 95% CI: 18.48-29.18, p < 0.00001) were associated with AVF failure. Furthermore, HDL-C was lower in the AVF failure group than in the AVF patency group (MD: -2.68, 95% CI: -4.60 to -0.76, p = 0.006).

CONCLUSION

Our analysis indicates that the AVF failure may be related to the increase of TC/LDL-C and the decrease of HDL-C. Although current guidelines do not consider intensive lipid-lowering therapy as necessary in patients undergoing HD, our research indicates that patients with AVF undergoing HD may need regular TC/LDL-C-lowering therapy to prevent AVF failure. However, this issue still needs well designed prospective trials.

Patency of arteriovenous fistulas and grafts for dialysis access: An analysis using the Korean National Health Insurance Service database from 2008 to 2019

BACKGROUND

Arteriovenous (AV) access practice and its outcomes vary internationally. To provide a better understanding of the patterns and outcomes of AV access creation, we investigated the patency and risk factors of arteriovenous fistulas (AVFs) and grafts (AVGs) as initial AV access in the Korean adult population using data from the last 10 years.

METHODS

The National Health Insurance Service database was queried retrospectively to identify patients undergoing hemodialysis with AVFs and AVGs as well as their clinical characteristics and outcomes from 2008 to 2019. AV access patency and its associated risk factors were evaluated.

RESULTS

During the study period, 64,179 AVFs and 21,857 AVGs were placed. The mean patient age was 62.6 ± 13.6 years (21.5% were ⩾75 years old), and 39.3% patients were women. More than half of the patients underwent AV access creation at tertiary care hospitals. At 1 year, the primary, primary assisted, and secondary patency rates were 62.2%, 80.7%, and 94.2% for AVFs, and 46.0%, 68.4%, and 86.8% for AVGs, respectively. AVG, older age, female sex, diabetes, and creation at general hospitals (vs tertiary hospitals) were associated with decreased patency outcomes (all, p < 0.05).

CONCLUSION

This study using national data showed that three quarters of patients with AV access had AVF and AVF showed superior performance to AVG and identified several patient and center factors related to AV access patency in Korea.

A scoping review of outcomes with routine surveillance of arterio-venous fistulas

The arteriovenous fistula (AVF) is the preferred venous access for maintenance haemodialysis. AVF dysfunction can progress to access failure, with all the associated morbidity and costs of revising vascular accesses. Routine surveillance of AVFs using specialised equipment has the potential to enable early detection of potential problems. The KDOQI Clinical Practice Guidelines for Vascular Access: Update 2019 suggest that surveillance may be useful to supplement regular clinical monitoring but acknowledge a lack of evidence to make firm recommendations. This scoping review of peer-reviewed literature explored outcomes with the routine surveillance of AVFs using specialised equipment in haemodialysis dependent adults. A systematic search was undertaken using terms such as 'vascular access', haemodialysis, surveillance and 'access flow', utilising the data bases ProQuest (Medline), CINAHL and Embase to include original research articles published between October 2016 and August 2022. A total of eight papers were identified for comprehensive analysis, including two randomised controlled trials, two cross-sectional studies, two retrospective reviews and two evaluations. Themes identified include the incidence of thrombotic events, the role of access blood flow measurements, the need for follow-up angiograms after surveillance and identification of the at-risk access. This review of research published in recent years demonstrated an ongoing paucity of evidence for the benefits of routine AVF surveillance. More research focused on actual outcomes is needed in this important area that is a routine part of dialysis unit workloads everywhere.

Vascular access interventional therapy of early arteriovenous fistula occlusion leading to long-term patency: A case report

Arteriovenous fistulas (AVFs) are frequently used for hemodialysis access, but approximately 15%-20% of AVFs fail to mature within 3 months of their creation. Vascular access interventional therapy (VAIVT) is typically performed for treating an immature AVF. However, it should be performed 4-6 weeks or later after AVF creation. Here, we present a case in which VAIVT effectively addressed AVF occlusion that occurred only 9 days after its creation. The patient was an 82-year-old woman with chronic kidney disease who underwent surgery to create a left radiocephalic AVF for hemodialysis. Nine days postoperatively, disappearance of the AVF sound prompted an angiography, revealing thrombosis near the AVF anastomosis. VAIVT successfully restored blood flow, resulting in AVF maturation, and with no thrombosis or flow dysfunction at 21 months after VAIVT. To the best of our knowledge, this case presents the earliest successful intervention for an occluded AVF.

Preoperative assessment for vascular access: Vascular mapping and handgrip strength

BACKGROUND

Reliable vascular access (VA) is required for patients receiving chronic hemodialysis (HD) treatment. Vascular mapping using duplex doppler ultrasonography (DUS) can aid in planning VA construction. Greater handgrip strength (HGS) was found to be associated with more developed distal vessels both in chronic kidney disease (CKD) patients and healthy individuals, and patients with lower HGS had worse morphologic vessel characteristics and were, therefore, less likely to construct distal VA.

OBJECTIVES

This study aims to describe and analyze clinical, anthropometric, and laboratory characteristics of patients who underwent vascular mapping prior to VA creation.

RESEARCH DESIGN

Prospective analysis.

SUBJECTS

Adult patients with CKD referred for vascular mapping, at a tertiary center, between March 2021 and August 2021.

MEASURES

Preoperative DUS by a single experienced nephrologist was carried out. HGS was measured using a hand dynamometer, and PAD was defined as ABI < 0.9. Sub-groups were analyzed according to distal vasculature size (<2 mm).

RESULTS

A total of 80 patients were included, with a mean age of 65.7 ± 14.7 years; 67.5% were male, and 51.3% were on renal replacement therapy (RRT). Twelve (15%) participants had PAD. HGS was higher in the dominant arm (20.5 ± 12.0 vs 18.8 ± 11.2 kg). Fifty-eight (72.5%) patients had vessels smaller than 2 mm in diameter. There were no significant differences between groups concerning demographics or comorbidities (diabetes, HTN, PAD). HGS was significantly higher in patients with distal vasculature greater than or equal to 2 mm in diameter (dominant arm: 26.1 ± 15.5 vs 18.4 ± 9.7 kg, p = 0.010; non-dominant arm: 24.1 ± 15.3 vs 16.8 ± 8.6, p = 0.008).

CONCLUSIONS

Higher HGS was associated with more developed distal cephalic vein and radial artery. Low HGS might be an indirect sign of suboptimal vascular characteristics, which might help predict the outcomes of VA creation and maturation.

Validation of arteriovenous access stage (AVAS) classification: a prospective, international multicentre study

Background

The arteriovenous access stage (AVAS) classification provides evaluation of upper extremity vessels for vascular access (VA) suitability. It divides patients into classes within three main groups: suitable for native fistula (AVAS1) or prosthetic graft (AVAS2), and patients not suitable for conventional native or prosthetic VA (AVAS3). We validated this system on a prospective dataset.

Methods

A prospective, international observational study (NCT04796558) involved 11 centres from 8 countries. Patient recruitment was from March 2021 to January 2024. Demographic data, risk factors, vessels parameters, VA types, AVAS class and early VA failure were collected. Percentage agreement was used to assess predictive ability of AVAS (comparison of AVAS and created VA) and consistency of AVAS assessment between evaluators. Pearson's Chi-squared test was used for comparison of early failure rate of conventional (predicted by AVAS) and unconventional (not predicted by AVAS) VA.

Results

From 1034 enrolled patients, 935 had arteriovenous fistula or graft, 99 patients did not undergo VA creation due opting for alternative renal replacement therapies, experiencing health complications, death or non-compliance. AVAS1 had 91.2%, AVAS2 7.2% and AVAS3 1.6% of patients. Agreement between evaluators was 89%. The most frequently created VAs were radial-cephalic (46%) and brachial-cephalic (27%) fistulae. The accuracy of AVAS versus created access was 79%. In comparison, VA predicted by clinicians versus created access was 62.1%. Inaccuracy of AVAS prediction was more common with higher AVAS classes, and the most common reason for inaccuracy was creation of distal VA despite less favourable anatomy (17%). Patients with unconventional VA had higher early failure rate than patients with conventional VA (20% vs 9.3%, respectively, P = .002).

Conclusion

AVAS is effective in predicting VA creation, but overall accuracy is reduced at higher AVAS classes when the complexity of decision-making increases and proximal vessels require preservation. When AVAS was followed by clinicians, early failure was significantly decreased.

The Pathological Mechanisms and Therapeutic Molecular Targets in Arteriovenous Fistula Dysfunction

The number of patients with end-stage renal disease (ESRD) requiring hemodialysis is increasing worldwide. Although arteriovenous fistula (AVF) is the best and most important vascular access (VA) for hemodialysis, its primary maturation failure rate is as high as 60%, which seriously endangers the prognosis of hemodialysis patients. After AVF establishment, the venous outflow tract undergoes hemodynamic changes, which are translated into intracellular signaling pathway cascades, resulting in an outward and inward remodeling of the vessel wall. Outward remodeling refers to the thickening of the vessel wall and the dilation of the lumen to accommodate the high blood flow in the AVF, while inward remodeling is mainly characterized by intimal hyperplasia. More and more studies have shown that the two types of remodeling are closely related in the occurrence and development of, and jointly determining the final fate of, AVF. Therefore, it is essential to investigate the underlying mechanisms involved in outward and inward remodeling for identifying the key targets in alleviating AVF dysfunction. In this review, we summarize the current clinical diagnosis, monitoring, and treatment techniques for AVF dysfunction and discuss the possible pathological mechanisms related to improper outward and inward remodeling in AVF dysfunction, as well as summarize the similarities and differences between the two remodeling types in molecular mechanisms. Finally, the representative therapeutic targets of potential clinical values are summarized.

Editor's Choice - Outcomes of Cold Stored Saphenous Vein Allografts for Haemodialysis Vascular Access

OBJECTIVE

The aim of this study was to evaluate the outcomes of cold stored saphenous vein allografts (CSVAs) for haemodialysis vascular access.

METHODS

A retrospective, two centre study was conducted between January 2016 and December 2020 of all patients who had CSVA placement for haemodialysis vascular access. Primary, primary assisted, and secondary patency were analysed, as well as procedural complications and re-interventions.

RESULTS

One hundred and nine patients (n = 55 women) with a mean age of 67.2 ± 13.6 years, with no options for creating an autogenous arteriovenous fistula, were included in the study. At one year, primary, primary assisted, and secondary patency were 37.6%, 59.0%, and 73.3%, respectively; and at two years 19.9%, 42.5%, and 54.9%, respectively. During a mean follow up period of 26 ± 18 months, five patients (4.6%) had an access infection, with no related death. During the follow up period, 32 patients (29.4%) died and 13 patients (11.9%) underwent a kidney transplant. None of these patients showed immunoconversion before transplantation. The cumulative incidence of adverse events by the Fine-Gray method was calculated. Considering competing risks (death and renal transplantation), 9.2% of patients lost their vascular access at one year and 18% at two years. Moreover, 57.8% patients had stenosis, mainly on the outflow (45.9%), and 49.5% had thrombosis.

CONCLUSION

With a comparable patency rate associated with a low infection rate, CSVA offers a potential alternative to expanded polytetrafluoroethylene grafts. This creates haemodialysis vascular access when the venous capital is exhausted in patients with reported risk factors for vascular access infection, i.e., insertion in the thigh, advanced age, diabetes mellitus, immunocompromised state, obesity, or revision of an infected prosthetic graft.

Drug-coated balloon for early recurrent arteriovenous fistula dysfunction

OBJECTIVE

To report the efficacy and safety of a drug-coated balloon (Ranger, Boston Scientific) in patients with dysfunctional autogenous arteriovenous fistula.

METHODS

In this investigator-initiated, prospective observational cohort study, 25 participants with dysfunctional arteriovenous fistula were enrolled from January 2018 to June 2019. The drug-coated balloon was applied after successful vessel preparation by high-pressure balloon angioplasty. The primary endpoint was the target lesion primary patency rate at 6 months. The secondary outcome included anatomical and clinical success rate, postoperative major adverse events within 30 days, and the target lesion primary patency rate at 12 months. Statistical analysis of the data was performed. The χ test or Fisher's exact test was used for analyzing categorical variables, and continuous variables were analyzed using Student's t-test. Also, Kaplan-Meier analysis was used to evaluate the target lesion primary patency days with the log-rank test.

RESULTS

At 6 months, the target lesion primary patency rate was 68% in the drug-coated balloon treatment group. The anatomical and clinical success rates were 100%. One patient had thrombosed access 10 days after the index procedure, and two died of cardiovascular events 4 months after the operation. Subgroup analysis showed that the early recurrent stenosis group had non-inferior mean drug-coated balloon primary patency days (less than 90 days after prior percutaneous angioplasty, n = 10) compared with the late recurrence group (prior PTA patency days more than 90 days, n = 10), 179.3 ± 102.9 versus 257.1 ± 71 days (p = 0.153). DCB angioplasty had significant improvement in primary patency days for early recurrent stenosis (67.7 ± 19.3 vs 179.3 ± 102.9, p < 0.001).

CONCLUSIONS

The results demonstrated the appliance of Ranger DCB in stenotic AVFs is a safe and effective treatment modality, especially for early recurrent AVF stenosis.

Comparative effectiveness of bovine carotid artery xenograft and polytetrafluoroethylene in hemodialysis access revision

BACKGROUND

When hemodialysis arteriovenous accesses fail, autogenous options are often limited. Non-autogenous conduit choices include bovine carotid artery xenografts (BCAG) and expanded polytetrafluoroethylene (PTFE), yet their comparative effectiveness in hemodialysis access revision remains largely unknown.

METHODS

A cohort study was performed from a prospectively collected institutional database from August 2010 to July 2021. All patients undergoing an arteriovenous access revision with either BCAG or PTFE were followed for up to 3 years from their index access revision. Revision was defined as graft placement to address a specific problem of an existing arteriovenous access while maintaining one or more of the key components of the original access (e.g. inflow, outflow, and cannulation zone). Outcomes were measured starting at the date of the index revision procedure. The primary outcome was loss of secondary patency at 3 years. Secondary outcomes included loss of post-intervention primary patency, rates of recurrent interventions, and 30-day complications. Pooled logistic regression was used to estimate inverse probability weighted marginal structural models for the time-to-event outcomes of interest.

RESULTS

A total of 159 patients were included in the study, and 58% received access revision with BCAG. Common indications for revision included worn out cannulation zones (32%), thrombosis (18%), outflow augmentation (16%), and inflow augmentation (13%). Estimated risk of secondary patency loss at 3 years was lower in the BCAG group (8.6%, 3.9-15.1) compared to the PTFE group (24.8%, 12.4-38.7). Patients receiving BCAG experienced a 60% decreased relative risk of secondary patency loss at 3 years (risk ratio 0.40, 0.14-0.86). Recurrent interventions occurred at similar rates in the BCAG and PTFE groups, with 1.86 (1.31-2.43) and 1.60 (1.07-2.14) interventions at 1 year, respectively (hazard ratio 1.22, 0.74-1.96).

CONCLUSIONS

Under the conditions of this contemporary cohort study, use of BCAG in upper extremity hemodialysis access revision decreased access abandonment when compared to PTFE.

Outcomes of brachial artery transposition in hemodialysis patients

OBJECTIVE

In hemodialysis patients with a difficult access extremity who are not suitable for an arteriovenous fistula or arteriovenous graft creation, the concept of cannulating a superficialized artery for arterial outflow in dialysis sessions has been adopted as a tertiary alternative. However, its long-term patency and complications have not been recognized widely. We report our 16-year experience with hemodialysis access creation using the brachial artery transposition (BAT) technique.

METHODS

This single-center retrospective study included consecutive patients who underwent BAT for hemodialysis vascular access between June 1, 2006, and December 31, 2022. The patency of the whole access circuit and the transposed brachial artery itself was evaluated independently.

RESULTS

In total, 193 surgical procedures were included. The success rate was 93.2%. The mean operative time was 128 minutes. The median interval from access placement to first cannulation was 21 days. The primary patency rates for BAT were 92.3%, 91.3%, 90.3%, 86.1%, and 71.9% at 1, 2, 3, 5, and 10 years, respectively. The secondary patency rates for BAT were 96.3%, 96.3%, 95.0%, 90.1%, and 74.9% at 1, 2, 3, 5, and 10 years, respectively. The primary patency rates for the whole access circuit were 61.4%, 49.2%, 45.8%, and 26.9% at 1, 2, 3, and 5 years, respectively. The secondary patency rates for the whole access circuit were 85.1%, 83.3%, 82.0%, and 68.6% at 1, 2, 3, and 5 years, respectively. The overall patient survival rates were 79.6%, 69.6%, 54.6%, 36.5%, and 13.4% at 1, 2, 3, 5 and 10 years, respectively. The abandonments of BAT were brachial artery thrombosis (n = 6), pseudoaneurysm (n = 2), aneurysmal change (n = 1), and other reasons (n = 1). The abandonments of the whole access circuit were exhaustion of venous return (n = 26), abandonment of BAT (n = 7), and other reasons (n = 2). Complications were exhaustion of venous return (n = 26), aneurysmal change (n = 12), pseudoaneurysm (n = 6), brachial artery thrombosis (n = 7), impaired wound healing (n = 19), lymphorrhea (n = 9), skin infection (n = 5), hematoma on cannulation (n = 3), and reduced peripheral blood flow (n = 2).

CONCLUSIONS

The patency of BAT was excellent, and that of the whole access circuit was adequate, with a few complications. BAT is an effective alternative from a long-term perspective for patients who are unsuitable for conventional hemodialysis access creation.

Effect of no-touch versus conventional technique on arteriovenous fistula outcomes: a randomised controlled trial

BACKGROUND

Autologous arteriovenous fistulae (AVFs) are the best type of vascular access in patients with kidney failure. However, the conventional technique has a high failure rate. We performed a randomised controlled trial to investigate whether the no-touch technique has a higher maturation and patency rate than that of the conventional technique for creating AVFs.

METHODS

This study was a single-centre randomised controlled trial involving patients with kidney failure requiring an AVF for haemodialysis access. A total of 179 patients undergoing their first radial artery-cephalic fistula were randomized 1:1 to the no-touch technique (n = 90) or conventional technique (n = 89). The maturation and patency rate of the two techniques were compared and analysed.

RESULTS

The preoperative baseline data showed no differences between groups. When comparing the no-touch technique to the conventional technique, the maturation rate was 93% vs. 89% and the 1-year primary function patency was 72% vs. 62%, respectively. Factors associated with AVF failure included age > 55 years (OR = 2.417, 95% CI 1.242-4.703), female sex (OR = 2.149, 95% CI 1.099-4.202), and vein diameter ≤ 1.8 mm (OR = 3.664, 95% CI 1.714-7.832). For patients with small veins the maturation rate was 92.98% vs. 80% and the 1-year primary function patency was 68.42% vs. 40% for the no-touch technique and conventional technique, respectively.

CONCLUSIONS

The no-touch technique has a higher maturation and patency rate than the conventional technique for creating an autologous AVF, especially in patients with small veins. This technique may provide a better outcome for patients with small cephalic veins.

Factors affecting suboptimal maturation of autogenous arteriovenous fistula in elderly patients with diabetes:A narrative review

Autogenous arteriovenous fistula (AVF) is considered the preferred vascular access choice for individuals undergoing maintenance hemodialysis (MHD) and is widely utilized in China, as reported by the Dialysis Outcomes and Practice Patterns Study. Despite its popularity, the significant incidence of poor AVF maturation often leads to the need for central venous catheter insertion, increasing the risk of complications like superior vena cava stenosis and catheter-related infections, which in turn raises the overall mortality risk. With the prevalence of diabetes rising globally among the elderly and diabetic kidney disease being a leading cause of end-stage renal disease necessitating renal replacement therapy, our retrospective review aims to explore the various factors affecting AVF maturation in this specific patient population. While there have been numerous studies examining AVF complications in MHD patients, including issues like failure, patency loss, stenosis, thrombosis, poor maturation, and other influencing factors, there remains a gap in large-scale clinical studies focusing on the incidence and risk factors for immature AVF specifically in elderly diabetic patients. This paper delves into the pathophysiological mechanisms, diagnostic criteria, and unique considerations surrounding AVF maturation in elderly diabetic patients, distinguishing them from the general population. Our literature review reveals that elderly diabetic patients exhibit a higher risk of AVF immaturity compared to the general population. Additionally, there exists a continuing discourse regarding several aspects related to this group, including the choice of dialysis access, timing of AVF surgery, and surgical site selection. Furthermore, we delve into the management strategies for vascular access within this specific group with the goal of providing evidence-based guidance for the establishment and maintenance of functional vascular access in elderly diabetic patients.

Beyond Conventional: A Systematic Review of Non-Conventional Techniques for Radio-Cephalic Arteriovenous Fistula

BACKGROUND

Radio-cephalic arteriovenous fistulas (RC-AVFs), the preferred vascular access for hemodialysis, have high failure rates. New techniques like the no-touch technique (NTT) and modified no-touch technique (MNTT) have shown promising results. Our objective is to highlight the effectiveness of nonconventional techniques, aiming to address the challenge of arteriovenous fistula (AVF) failure.

METHODS

We searched Medline, Google Scholar, and Clinicaltrials.gov until April 2023, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Five relevant articles were found, all involving human studies on NTT or MNTT for RC-AVF creation. We focused on primary and secondary patency rates, fistula maturation rates, and complications.

RESULTS

We reviewed 5 studies as follows: 2 were pilot studies, 2 were prospective studies, and one was retrospective study. Three used NTT, and 2 used MNTT. Among double-arm studies, 3 out of 4 showed a significantly improved primary patency with nonconventional techniques. However, one study found no significant difference between nonconventional and conventional methods (90.5% vs. 84.2%; P = 0.225). In a single-arm study, nonconventional technique (NTT) displayed 54% primary patency at 1 year. Secondary patency rates were in 3 studies. One demonstrated significant secondary patency with nonconventional methods compared to conventional (90% vs. 67.5%; P = 0.028), while another found no significant difference (90.5% vs. 84.2%; P = 0.803). In the single-arm study, the nonconventional technique (NTT) revealed 80% secondary patency at 1 year.

CONCLUSIONS

Nonconventional techniques (NTT and MNTT) show promise in improving patency rates, hinting at their potential as alternatives to the conventional technique for RC-AVF creation. Further studies are crucial to confirm their effectiveness and evaluate long-term outcomes.

Ultrasound-guided nitinol stent implantation to treat early restenosis of arteriovenous fistula: A 69-case study with 1-year outcome

BACKGROUND

To investigate the feasibility, methods and effects of interventional ultrasound in nitinol stent implantation to treat early restenosis after percutaneous transluminal angioplasty (PTA) in autogenous arteriovenous fistula (AVF).

METHODS

From April 2018 to December 2021, 69 patients with early restenosis of AVF received ultrasound-guided nitinol stent implantation (UNSI) and were followed-up. Imaging features of the stent and procedure by ultrasound were observed. The technical success rate, clinical success rate and incidence of complications were recorded and counted. Target lesion primary patency (TLPP), access circuit primary patency (ACPP) and access circuit secondary patency (ACSP) were estimated.

RESULTS

Ultrasonography can show the structure of the stent and guide the stenting process clearly. Both the technical and clinical success rates were 100%. Thirty-one patients had in-stent restenosis (ISR), which was treated by plain balloon (PB) PTA or drug coated balloon (DCB) PTA. The TLPP at 3, 6, 12 and 24 months were 100.0%, 94.2%, 63.4% and 39.6%, respectively. The ACPP at 3, 6, 12 and 24 months were 98.6%, 91.6%, 60.2% and 35.2%, respectively. The ACSP at 3, 6, 12 and 24 months were 98.6%, 98.6%, 95.6% and 93.8%, respectively. The TLPP of ISR after DCB PTA at 3, 6 and 12 months were 100.0%, 100.0% and 93.6%, respectively.

CONCLUSIONS

This pilot study indicates ultrasonography can accurately guide nitinol stent implantation in AVF and this technique is a feasible and minimally invasive treatment for early restenosis after PTA with good short- and medium-term patency. DCB PTA may be used to deal with the ISR and is a way to prolong the patency of nitinol stent.

The Use of a High Flow PICC Catheter for Stem Cell and Lymphocyte Apheresis: The Initial Experience of a Pediatric Oncology Center in Brazil

BACKGROUND

Autologous hematopoietic stem cell transplant (HSCT), characterized by high intensity chemotherapy followed by the infusion of HSC previously collected from the peripheral blood, is a procedure used in the treatment of several malignancies. In pediatrics, the apheresis procedure represents a challenge, due to the need for insertion of a rigid central venous catheter (CVC) in small children. The CVC is usually used for stem cell collection and then removed. Later, the patient will need a new device for cell infusion.

AIM

We propose the use of one single catheter for both apheresis and infusion.

METHODS

We present five children between 1 and 13 years of age who underwent apheresis using a high flow PICC catheter surgically inserted.

RESULTS

All patients utilized a PICC line double lumen 5Fr (PowerPICC™ 5Fr DL BARD/USA) placed in the brachiocephalic vein tunneled on the chest, inserted under 24 h prior to apheresis to assure the devices were pervious. Three of the patients were diagnosed with solid tumor and one with acute lymphoblastic leukemia (ALL) awaiting Car-T Cell therapy. The four children who underwent autologous HSCT used the same catheter for cell infusion and remained with the catheter following discharge. The child who was submitted for Car-T Cell still awaits infusion and the catheter was removed.

CONCLUSIONS

High flow PICC is a viable alternative for apheresis to maintain an adequate flow of 5 ml/s and can be used as a single catheter throughout the HSCT process, reducing the risks from anesthesia and the catheter insertion procedure.

TYPE OF STUDY

Clinical Research.

Association of anesthetic modality and other variables on 1-year functional patency of cephalic-based arteriovenous fistulae

OBJECTIVE

Some studies suggest that regional anesthesia provides better patency for arteriovenous fistula (AVF) for hemodialysis access as compared to local and general anesthesia. This study evaluates the impact of anesthetic modality on long term fistula function at 12 months.

METHODS

A retrospective review of patients undergoing cephalic vein-based hemodialysis access in consecutive cases between 2014 and 2019 was conducted from five safety net hospitals. The primary endpoint was functional patency at 12 months. Subset analysis individually evaluated cephalic-based lower forearm and wrist vs upper arm AVFs. Bivariate and multivariate logistic regression models evaluated the relationship between anesthetic modality and fistula function at 12 months.

RESULTS

There were 818 cephalic-based fistulas created during the study period. The overall 12-month functional patency rate was 78.7%, including an 81.3% patency for upper arm AVF and 73.3% for wrist AVF (P = .009). There was no statistically significant difference among patients with functional and nonfunctional AVFs at 12 months with respect to anesthetic modality when comparing regional, local, and general anesthesia (P = .343). Multivariate regression analysis identified that history of AVF/arteriovenous graft (odds ratio [OR], 0.24; P = .007), receiving intraoperative systemic anticoagulation (OR, 2.49; P < .001), and vein diameter (OR, 1.85; P = .039) as independently associated with AVF functional patency at 12 months.

CONCLUSIONS

There was no association between anesthetic modality and functional patency of cephalic-based AVFs at 12 months. Further studies are needed to better define which patients may benefit from regional anesthesia.

Central Venous Catheter Complications in the Poisoning Emergency Center: A 5-Year Cross-Sectional Study

Background

Central venous catheters (CVCs) are used widely in emergency centers, which may be associated with complications. There is a paucity of literature focusing on CVC complications, specifically in the poisoning emergency centers. In this study, we determined the frequency of CVC complications in patients with acute poisoning.

Materials and Methods

This was a cross-sectional study performed in the poisoning referral center. We reviewed the medical records of patients with acute poisoning who underwent CVC at the time of admission/during hospitalization in the poisoning intensive care unit or poisoning ward and were hospitalized between 2014 and 2019.

Results

During the study period, 33, l37 patients with acute poisoning had been admitted and CVC was placed for 400 patients (1.20% of total patients). Most of the CVCs had been placed via femoral (51%) (204 cases). The frequency of CVC complications was 13.75%. The CVC in the internal jugular (IJ) vein was associated with a higher complication (20.7%) (P value 0.02). Infection (9.2%) and pneumothorax (9.2%) were more observed with the IJ approach, while arterial puncture was more observed with subclavian (3.7%) (P value < 0.0001).

Conclusions

The frequency of CVC placement in acute poisoning patients was not noticeable. Although the femoral vein was the most commonly used approach in our institution, overall complications were more observed with the IJ vein approach.

Nurses' knowledge, attitudes, and practices on CLABSI prevention in the Intensive Care Unit: An observational study

BACKGROUND

Management of central venous catheters (CVC) is a frequent procedure in intensive care units (ICUs) and the risk of bloodstream infections (CLABSI) is found to be high. The literature provides healthcare professionals with guidelines to prevent the risk of CLABSI infections. The aim of this study was to observe the knowledge, attitudes, and practices of ICU nurses on the prevention of CLABSI.

METHODS

A multicenter cross-sectional study was conducted between March 2023 and September 2023; the research was carried out among six ICUs in Bari both on the web and in paper mode. The survey consisted of multiple-choice questions structured in two sections: demographic sample data and the 2017 Esposito MR questionnaire, drawn up based on the 2011 guidelines of the Centers for Disease Control and Prevention, consisting of four dimensions: knowledge, attitudes, practices, information.

RESULTS

121 nurses (57.1%) participated in the study. 72% were unfamiliar with the guidelines, especially nurses aged 41-50 years (RR = 1.88; CI = 0.78-4.51; p = 0.13) and more than 10 years' work experience (RR = 1.56; CI = 0.76-3.23; p = 0.20). Regarding attitudes, nurses were aware of the usefulness of the guidelines (Me = 10; IQR = 8-10) and the importance of hand washing for prevention (Me = 10; IQR = 10-10) despite 39.7% (n = 48) believing that gloves replace hand washing, and there were no statistically significant differences in comparing scores with age, work experience, and educational qualification. 96.7% always substituted dressing for CVC; 120 nurses (99.2%) were always replacing infusion sets and 71.2% always sanitized the access ports before infusions. Finally, 102 participants (84.3%) felt the need to get more information about the prevention of CLABSI.

CONCLUSIONS

We observed a reduced knowledge of the guidelines for the prevention of CLABSI despite the attitudes and practices of the nurses being satisfactory. In addition to implementing training, strategies for disseminating guidelines should be adopted.

The Effectiveness of Electronic Cannulation Atlas in Patients with Arteriovenous Fistula

Objective

This study aimed to assess the effectiveness of an electronic cannulation atlas in preventing and treating complications of arteriovenous fistula.

Methods

The observation group, consisting of 92 dialysis patients from July to December 2021, was managed with an electronic cannulation atlas. After 6 months, the incidence of complications such as stenosis, hematoma, thrombus, aneurysm, and cannulation failure was compared between the groups. Nurse satisfaction with the electronic cannulation atlas system was also assessed through a questionnaire.

Results

The observation group had lower incidence rates of arteriovenous fistula stenosis, thrombus, aneurysm, and failure rate of cannulation compared to the control group, with statistically significant differences (p<0.05). The incidence rates of hematoa were similar in both groups, showing no significant difference (p>0.05). After 3 months of management, the incidence of arteriovenous fistula complications in the observation group was significantly lower than in the control group (p<0.05). Additionally, utilizing the electronic cannulation atlas system was found to increase nurses' job satisfaction.

Conclusion

The use of electronic cannulation atlas for the treatment of patients' arteriovenous fistula could effectively reduce the incidence of complications of patients' arteriovenous fistula, reduce the failure rate of cannulation, reduce the workload of nurses, and improve the job satisfaction of nurses.

Off-the-Shelf Synthetic Biodegradable Grafts Transform In Situ into a Living Arteriovenous Fistula in a Large Animal Model

Current vascular access options require frequent interventions. In situ tissue engineering (TE) may overcome these limitations by combining the initial success of synthetic grafts with long-term advantages of autologous vessels by using biodegradable grafts that transform into autologous vascular tissue at the site of implantation. Scaffolds (6 mm-Ø) made of supramolecular polycarbonate-bisurea (PC-BU), with a polycaprolactone (PCL) anti-kinking-coil, are implanted between the carotid artery and jugular vein in goats. A subset is bio-functionalized using bisurea-modified-Stromal cell-derived factor-1α (SDF1α) derived peptides and ePTFE grafts as controls. Grafts are explanted after 1 and 3 months, and evaluated for material degradation, tissue formation, compliance, and patency. At 3 months, the scaffold is resorbed and replaced by vascular neo-tissue, including elastin, contractile markers, and endothelial lining. No dilations, ruptures, or aneurysms are observed and grafts are successfully cannulated at termination. SDF-1α-peptide-biofunctionalization does not influence outcomes. Patency is lower in TE grafts (50%) compared to controls (100% patency), predominantly caused by intimal hyperplasia. Rapid remodeling of a synthetic, biodegradable vascular scaffold into a living, compliant arteriovenous fistula is demonstrated in a large animal model. Despite lower patency compared to ePTFE, transformation into autologous and compliant living tissue with self-healing capacity may have long-term advantages.

Intrastent HeROgraft deployment as a catheter-sparing procedure

Current vascular access (VA) practice adopts arteriovenous fistulas (AVF) as first option for haemodialysis, relegating arteriovenous grafts (AVG) for patients with exhausted upper limb venous patrimony. The Hemodialysis Reliable Outflow graft (HeRO®) is a device assuring direct venous outflow to the right atrium, thus avoiding central venous obstructive disease. Its use together with early access grafts avoids the need for central venous catheters (CVC) bridging periods. We report the deployment of the HeRO device using a previous stentgraft as pathway for the placement of the outflow component, in a patient with no-option for further autogenous upper limb access. This technique spared the usual central vein's exit point for the HeRO graft and, using an early-access dialysis graft, allowed for next-day successful haemodialysis.

Study protocol of a prospective single-arm multicenter clinical study to assess the safety and performance of the aXess hemodialysis graft: The pivotal study

BACKGROUND

Arteriovenous grafts (AVGs) are used for patients deemed unsuitable for the creation of an autogenous arteriovenous fistula (AVF) or unable to await maturation of the AVF before starting hemodialysis. However, AVGs are prone to infection and thrombosis resulting in low long-term patency rates. The novel aXess Hemodialysis Graft consists of porous polymeric biomaterial allowing the infiltration by cells and the growth of neotissue, while the graft itself is gradually absorbed, ultimately resulting in a fully functional natural blood vessel. The Pivotal Study will examine the long-term effectiveness and safety of the aXess Hemodialysis Graft.

METHODS

The Pivotal Study is a prospective, single-arm, multicenter study that will be conducted in 110 subjects with end-stage renal disease who are not deemed suitable for the creation of an autogenous vascular access. The primary efficacy endpoint will be the primary patency rate at 6 months. The primary safety endpoint will be the freedom from device-related serious adverse events at 6 months. The secondary endpoints will include the procedural success rate, time to first cannulation, patency rates, the rate of access-related interventions to maintain patency, the freedom from device-related serious adverse events and the rate of access site infections. Patients will be followed for 60 months. An exploratory Health Economic and Outcomes Research sub-study will determine potential additional benefits of the aXess graft to patients, health care institutions, and reimbursement programs.

DISCUSSION

The Pivotal study will examine the long-term performance and safety of the aXess Hemodialysis Graft and compare the outcome measures with historical data obtained with other graft types and autogenous AVFs. Potential advantages may include superior long-term patency rates and lower infection rates versus currently available AVGs and a shorter time to first cannulation compared to an autologous AVF. As such, the aXess Hemodialysis Graft may fulfill an unmet clinical need in the field of hemodialysis access.

Treatment of arteriovenous access pseudoaneurysms using ultrasound guided balloon assisted thrombin injection: Two cases and systematic review of the literature

BACKGROUND

Arteriovenous fistula pseudoaneurysm (AVF-PSA) is a common complication, usually caused during dialysis cannulation, which traditionally has been treated with open and less frequently endovascular techniques. Thrombin injection, although established in the treatment of arterial pseudoaneurysms, has barely been used in the treatment of AVF-PSA, due to concerns for AVF thrombosis or proximal embolization.

METHODS

A systematic review was performed according to the PRISMA 2020 guidelines. PubMed and Cochrane Central databases were reviewed and all clinical reports on AVF-PSA balloon assisted percutaneous thrombin injection through July 2022 were included. The electronic search yielded five case reports. Due to between-study differences and small sample size, the findings were summarized from each report, but the results were not pooled. Additionally, we present our own experience on two patients with AVF-PSA that were treated with balloon assisted percutaneous thrombin injection.

RESULTS

A total of five case reports (no of patients: 7, including ours) were included for review. Most of the patients were male (n = 6) and the mean age was 65.9 years. The average size of the PSA was 1.6 cm. In all cases a balloon was inflated to prevent thrombin and thrombotic material intrusion into the fistula lumen, prior to thrombin injection. In one patient n-butyl cyanoacrylate and Lipiodol were used, due to thrombin non availability. Recurrence was reported in only one patient, and average follow-up is 16 months.

CONCLUSIONS

Thrombin injection with concomitant balloon inflation seems to be a safe and effective treatment for arteriovenous fistula pseudoaneurysms. Future studies should be aimed at evaluating the long-term outcomes of such minimally invasive techniques.

Intraoperative transit time flow measurement predicts maturation of radiocephalic arteriovenous fistulas

OBJECTIVE

The arteriovenous fistula (AVF) is the first choice for gaining vascular access for hemodialysis. However, 20% to 50% of AVFs fail within 4 months after creation. Although demographic risk factors have been described, there is little evidence on the intraoperative predictors of AVF maturation failure. The aim of this study was to assess the predictive value of intraoperative transit time flow measurements (TTFMs) on AVF maturation failure.

METHODS

In this retrospective cohort study, intraoperative blood flow, measured using TTFM, was compared with AVF maturation after 6 weeks in 55 patients. Owing to its significantly higher prevalence and risk of nonmaturation, the radiocephalic AVF (RCAVF) was the main focus of this study. A recommended cutoff point for high vs low intraoperative blood flow was determined for RCAVFs, using a receiver operating characteristic curve.

RESULTS

The average intraoperative blood flow in RCAVFs was 156 mL/min. Patients with an intraoperative blood flow equal or lower than the determined cutoff point of 160 mL/min, showed a 3.03 times increased risk of AVF maturation failure after 6 weeks, compared with patients with a higher intraoperative blood flow (P < .001).

CONCLUSIONS

The intraoperative blood flow in RCAVFs measured by TTFM provides an adequate means of predicting AVF nonmaturation 6 weeks after surgery. For RCAVFs, a cutoff point for intraoperative blood flow of 160 mL/min is recommended for maximum sensitivity and specificity to predict AVF maturation failure after 6 weeks.

Long-Term Experience of Arterio-Venous Fistula Surgery in Children on Hemodialysis

Background: Arterio-venous fistulas (AVF) are used as first-line access for hemodialysis (HD) in the pediatric population. The aim of this investigation was to describe a single-center experience in the creation of AVF, together with its patency in children. Methods: This single-center retrospective study included all patients aged ≤18 years with AVFs created between 1993 and 2023. The collected data included patients' demographics, hemodialysis history, intraoperative data, and required reinterventions in order to determine the impact of these variables on primary, primary-assisted, and secondary patency. Results: Fifty-seven patients were analyzed with a median age of 15 years (range, 7-18 years). Fifty-four forearm and four upper arm fistulas were performed. The median follow-up was 6.9 years (range, 0-23 years). The primary failure rate was 10.5%. The primary patency rate was 67.6%, 53.6%, 51.4%, and 38.1% after 1, 3, 5, and 10 years; primary-assisted patency was 72.9%, 62.8%, 60.6%, and 41.5%; and secondary patency was 87.3%, 81.3%, 76.8%, and 66.6% after 1, 3, 5, and 10 years in the studied population. Conclusions: AVFs showed an acceptable rate of primary failure and excellent long-term patency. In this context, AVFs are an appropriate option for HD access, especially in pediatric patients.

HeRO graft-The results of the cologne single center study

OBJECTIVE

The HeRO graft is a technique for vascular access in patients with limited treatment options; however, the published results with the HeRO graft are diverging. We therefore conducted a single-center study.

METHODS

Patient records between July 2014 and February 2020 from Vascular Access Unit of the Department of Vascular and Endovascular Surgery of University Clinic of Cologne (Germany) were reviewed. Retrospective data was analysed from patients with a HeRo graft (n = 18).

RESULTS

Eighteen patients were enrolled in the study. The mean age of the patients was 62.8 ± 17.24 years. During the follow-up period, no patients died from complications related to the HeRO graft. Each patient had a mean of 1.94 concomitant diseases. The primary patency rates of the HeRO graft at 3, 6, 12, 18, and 24 months were 61.1%, 50%, 16.7%, 11.1%, and 5.6%, respectively. The secondary patency rates at the same time intervals were 77.8%, 72.8%, 55.6% 55.6%, and 55.6%, respectively. There were 44 re-operations per year, or 2.4 operations per patient. The main cause of acute complications was acute graft occlusions after HERO graft implantation. An infection after the graft implantation occurred in five (27.7%) patients, leading to graft explanation in 2 cases.

CONCLUSION

The use of the HERO graft is a valuable alternative method for providing a durable dialysis access in patients with limited access options. The secondary patency and survival are good with a low infection rate.

Challenges of Predicting Arteriovenous Access Survival Prior to Conversion from Catheter

OBJECTIVE

The decision to convert from catheter to arteriovenous access is difficult yet very important. The ability to accurately predict fistula survival prior to surgery would significantly improve the decision making process. Many previously investigated demographic and clinical features have been associated with fistula failure. However, it is not conclusively understood how reliable predictions based on these parameters are at an individual level. The aim of this study was to investigate the probability of arteriovenous fistula maturation and survival after conversion using machine learning workflows.

METHODS

A retrospective cohort study on multicentre data from a large North American dialysis organisation was conducted. The study population comprised 73 031 chronic in centre haemodialysis patients. The dataset included 49 variables including demographic and clinical features. Two distinct feature selection and prediction pipelines were used: LASSO regression and Boruta followed by a random forest classifier. Predictions were facilitated for re-conversion to catheter within one year. Additionally, all cause mortality predictions were conducted to serve as a comparator.

RESULTS

In total, 38 151 patients (52.2%) had complete data and made up the main cohort. Sensitivity analyses were conducted in 67 421 patients (92.3%) after eliminating variables with a high proportion of missing data points. Selected features diverged between datasets and workflows. A previously failed arteriovenous access appeared to be the most stable predictor for subsequent failure. Prediction of re-conversion based on the demographic and clinical information resulted in an area under the receiver operating characteristic curve (ROCAUC) between 0.541 and 0.571, whereas models predicting all cause mortality performed considerably better (ROCAUC 0.662 - 0.683).

CONCLUSION

While group level depiction of major adverse outcomes after catheter to arteriovenous fistula or graft conversion is possible using the included variables, patient level predictions are associated with limited performance. Factors during and after fistula creation as well as biomolecular and genetic biomarkers might be more relevant predictors of fistula survival than baseline clinical conditions.

Application of modified no-touch technique in rabbit arteriovenous fistula model and its effect on venous neointimal hyperplasia

BACKGROUND

To investigate the technical advantages of a modified no-touch technique (MNTT) in constructing arteriovenous fistulas (AVF) compared to the conventional technique (CT) and assess its potential to reduce neointimal hyperplasia in the outflow vein.

METHODS

Forty-seven New Zealand rabbits were randomly divided into three groups: control, CT, and MNTT. Rabbits in control group were observed using ultrasound and then euthanized to obtain external jugular vein (EJV) for Hematoxylin-eosin (H-E). We established common carotid artery (CCA)-EJV AVF using MNTT in the MNTT group and the CT in the CT group. AVF patency and complications were compared between the CT and MNTT groups. Rabbits with patent AVF in both groups were observed using ultrasound 2 weeks after surgery to evaluate changes in the vessel diameter and blood flow spectrum of the AVFs. H-E staining measured the intima thickness of EJV adjacent to the anastomosis and histologic characteristics of the AVF at 2 and 4 weeks after surgery.

RESULTS

Five rabbits died after surgery with common symptoms of sneezing, coughing, runny nose, anorexia, and diarrhea; two in the MNTT group and three in the CT group. There were significant differences in the diameter (p = 0.010) and peak systolic velocities (PSV) (p = 0.001) of EJV between the CT and MNTT groups 2 weeks after surgery. Spiral laminar flow (SLF) was observed in CCA and EJV adjacent to anastomosis in the MNTT group. Additionally, histological observations showed less venous neointimal hyperplasia in the MNTT group than in the CT group 4 weeks after surgery.

CONCLUSION

The rabbit model of CCA-EJV AVF established using MNTT demonstrated fewer complications, larger vein diameters, and reduced venous neointimal hyperplasia, indicating that this maybe an ideal animal model to further investigate the application of MNTT in AVF surgery.

Clinical outcomes and predictive factors of stent grafts treatment for symptomatic central venous obstruction in end stage kidney disease patients with arteriovenous access

To assess the efficacy of stent grafts (SGs) in managing central venous obstruction disease (CVOD) in hemodialysis (HD) patients with arteriovenous (AV) access, and to identify predictive factors influencing the SG treatment outcomes. HD subjects with CVOD who underwent SGs placement at our center between August 2018 and June 2022 were enrolled. Survival curve analysis using the Kaplan-Meier method and log-rank test was performed. Cox proportional hazards regression analysis was employed to identify predictive factors associated with outcomes. A total of 59 SG implantation procedures for CVOD were analyzed, comprising 30 cases of stenosis and 29 cases of occlusion. The access circuit primary patency (ACPP) at 6, 12, and 24 months post-SG placement were 80.9%, 53.8%, and 31.4%, respectively, while, the target lesion primary patency (TLPP) were 91.3%, 67.6%, and 44.5%, respectively. Subgroup analysis revealed higher TLPP in the stenosis group compared to the occlusion group, although the difference was not statistically significant (P = 0.165). The TLPP was significantly improved by SG placement in those who had antecedent balloon dilations (P < 0.001). Cox proportional hazards regression identified target lesion length ≥ 30 mm and procedure defects as independent predictors of lower TLPP after SG treatment for CVOD in HD patients. SG placement demonstrates safety and efficacy in managing CVOD among HD patients, leading to improved TLPP of endovascular therapy (EVT) for CVOD. Notably, long target lesions (≥ 30 mm) and procedure defects emerged as predictive factors influencing TLPP.

A review of the current recommendations and practices for hemodialysis access monitoring and maintenance procedures

The growing number of prevalent arteriovenous (AV) accesses has been associated with an increase in the incidence of procedures being performed to maintain patency. To reduce the rate of unnecessary procedures, the 2019 Kidney Disease Outcome Quality Initiative guidelines addended the AV access surveillance recommendations, which includes clinical monitoring and assessment of dialysis adequacy alone. Abnormal clinical findings would necessitate follow-up angiography with or without confirmatory duplex ultrasound. Due to poor patency, increased surveillance schedules have been proposed to identify stenosis early and potentially prevent acute thrombotic events and AV access failure. In this review, we outlined current AV access monitoring and maintenance procedure recommendations, as described by the Centers for Medicare and Medicaid Services and 2019 Kidney Disease Outcome Quality Initiative guidelines. In addition, we highlight the findings of recently published randomized controlled trials that have examined increased surveillance schedules.

Temporal trends in hemodialysis access creation during the fistula first era

OBJECTIVE

Although forearm arteriovenous fistulas (AVFs) are the preferred initial vascular access for hemodialysis based on national guidelines, there are no population-level studies evaluating trends in creation of forearm vs upper arm AVFs and arteriovenous grafts (AVGs). The purpose of this study was to report temporal trends in first-time permanent hemodialysis access type, and to assess the effect of national initiatives on rates of AVF placement.

METHODS

Retrospective cross-sectional study (2012-2022) utilizing the Vascular Quality Initiative database. All patients older than 18 years with creation of first-time upper extremity surgical hemodialysis access were included. Anatomic location of the AVF or AVG (forearm vs upper arm) was defined based on inflow artery, outflow vein, and presumed cannulation zone. Primary analysis examined temporal trends in rates of forearm vs upper arm AVFs and AVGs using time series analyses (modified Mann-Kendall test). Subgroup analyses examined rates of access configuration stratified by age, sex, race, dialysis, and socioeconomic status. Interrupted time series analysis was performed to assess the effect of the 2015 Fistula First Catheter Last initiative on rates of AVFs.

RESULTS

Of the 52,170 accesses, 57.9% were upper arm AVFs, 25.2% were forearm AVFs, 15.4% were upper arm AVGs, and 1.5% were forearm AVGs. From 2012 to 2022, there was no significant change in overall rates of forearm or upper arm AVFs. There was a numerical increase in upper arm AVGs (13.9 to 18.2 per 100; P = .09), whereas forearm AVGs significantly declined (1.8 to 0.7 per 100; P = .02). In subgroup analyses, we observed a decrease in forearm AVFs among men (33.1 to 28.7 per 100; P = .04) and disadvantaged (Area Deprivation Index percentile ≥50) patients (29.0 to 20.7 per 100; P = .04), whereas female (17.2 to 23.1 per 100; P = .03), Black (15.6 to 24.5 per 100; P < .01), elderly (age ≥80 years) (18.7 to 32.5 per 100; P < .01), and disadvantaged (13.6 to 20.5 per 100; P < .01) patients had a significant increase in upper arm AVGs. The Fistula First Catheter Last initiative had no effect on the rate of AVF placement (83.2 to 83.7 per 100; P=.37).

CONCLUSIONS

Despite national initiatives to promote autogenous vascular access, the rates of first-time AVFs have remained relatively constant, with forearm AVFs only representing one-quarter of all permanent surgical accesses. Furthermore, elderly, Black, female, and disadvantaged patients saw an increase in upper arm AVGs. Further efforts to elucidate factors associated with forearm AVF placement, as well as potential physician, center, and regional variation is warranted.

Arteriovenous access creation and hazards of hospitalization and death in patients starting hemodialysis

BACKGROUND

Recent evidence suggests an overestimation of the benefits associated with arteriovenous (AV) fistula versus graft in certain populations. We assessed hazards of all-cause and cause-specific hospitalization and death associated with AV access type in patients who started hemodialysis with a catheter in France, overall and by subgroups of age, sex and comorbidities.

METHODS

We performed a target trial emulation including patients who initiated hemodialysis with a catheter from 2010 through 2018 and were followed by the REIN Registry. We identified first-created fistula or graft through the French national health-administrative database. We used joint frailty models to deal with recurrent hospitalizations and potential informative censoring by death, and inverse probability weighting to account for confounding.

RESULTS

From the 18 800 patients included (mean age 68 ± 15 years, 35% women), 5% underwent AV graft creation first. The weighted hazard ratio (wHR) of all-cause hospitalization associated with graft was 1.08 [95% confidence interval (CI) 1.02 to 1.15], that of vascular access-related hospitalization was 1.43 (95% CI 1.32 to 1.55), and those of cardiovascular- and infection-related hospitalizations were 1.14 (95% CI 1.03 to 1.26) and 1.11 (95% CI 0.97 to 1.28), respectively. Results were consistent for most subgroups, except that the highest hazard of all-cause, cardiovascular- and infection-related hospitalizations with graft was blunted in patients with comorbidities (i.e. diabetes, wHR 1.01, 95% CI 0.93 to 1.10; 1.10, 95% CI 0.96 to 1.26; and 0.94, 95% CI 0.78 to 1.12, respectively).

CONCLUSIONS

In patients starting hemodialysis with a catheter, AV graft creation is associated with increased hazard of vascular access-related hospitalizations compared with fistula. This may not be the case for death or other causes of hospitalization.