Arteriovenous Fistula Outcomes Research Articles

Similar outcomes of arteriovenous fistulae created under general or regional anesthesia.

There is growing evidence that type of anesthesia can significantly change vascular access surgery outcomes. Still, there is limited evidence on the impact of regional anesthesia (RA) on patency and failure rates compared to general anesthesia (GA). The aim of this study was to compare the outcomes of RA and GA in patients who underwent vascular access creation at our center. Data collected in our prospectively maintained database of patients with chronic renal dysfunction requiring hemodialysis were analyzed, 464 patients were included. Outcome parameters such as maturation, primary failure, postoperative flow measurements, patency rates, and survival outcomes were compared between RA and GA groups. In this study 489 vascular access procedures were performed in 464 patients, 318 included in the RA group and 171 in the GA group. Median follow-up time was 29.9 (IQR 37.3) months in the RA group versus 33.0 (IQR 40.7) in the GA group (p = 0.252). Anesthesia type did not significantly affect patient survival (HR, 1.01; CI, 0.70-1.45; p = 0.976). No significant differences were found in vascular access flow volume, primary failure, or time to cannulation between the RA and GA groups for both radiocephalic arteriovenous fistulae and brachiocephalic arteriovenous fistulae. Anesthesia type did not significantly change patency outcomes. Based on our results, both RA and GA demonstrate similar results regarding patient survival, maturation, failure, or patency after vascular access creation. Still, patient-specific factors for each type of anesthesia as well as patient preference should be considered.

Clinical features, treatment, and outcomes of cavernous sinus dural arteriovenous fistulas: a cohort study of 141 patients.

The cavernous sinus (CS) region is a common region of dural arteriovenous fistula (DAVF). Over time, treatment strategies are gradually changing. In this study, we present our center's experience in managing CS-DAVF over the past 20years. Medical records of patients diagnosed with CS-DAVF between 2002 and 2021 were collected for analysis. Patients meeting the predefined inclusion and exclusion criteria were included. This study summarized and analyzed their clinical characteristics, CS-DAVF angioarchitecture, treatment strategies, and outcomes. A total of 141 patients (mean age 55years, 46 males) were included in this study. Ocular/orbital symptoms were the most frequently reported initial symptoms, with 84 (59.6%) patients experiencing these symptoms first. Presentation with ocular/orbital symptoms as the first symptom was associated with thrombosis of the inferior petrosal sinus (p = 0.032). Presentation with headache/dizziness and tinnitus/intracranial murmur as the first symptom was associated with sphenoparietal sinus/superficial middle cerebral vein drainage (p = 0.011). Among the patients, 131 (92.9%) patients received endovascular treatment, with 114 (87.0%) undergoing transvenous embolization. Onyx (92.4%) and coil (74.8%) were the most used embolic materials. 17 (13.0%) of the patients who received endovascular treatment suffered intraoperative or postoperative complications, and 11 (64.7%) patients fully recovered within 6months after discharge. Ocular/orbital symptoms were the most common first symptom of CS-DAVF. The mode of venous drainage played a significant role in determining the first symptoms. Transvenous embolization using Onyx or a combination of Onyx and coils was the primary treatment modality.

Standardization of Pre-operative Evaluation to Improve the Outcome of Arteriovenous Fistula for Vascular Access of Hemodialysis: A Review of 700 Cases.

Background With the advent of COVID-19, mortality rates of end-stage kidney disease (ESKD) rose by 37% which makes its treatment an important part of healthcare. Arteriovenous fistula (AVF) is linked to higher patient survival rates. Cimino-Brescia fistula is the most effective vascular access technique, but it has a high rate of primary failure (PF) and a several-week maturation period before it can be used. The current study aims to verify the preoperative evaluation in improving survival among AVF patients. Methodology The current study is a retrospective analysis of the hospital database from Jan 2022 to July 2023, with patients of a mean age of 60.2 years. The sample size was around 700, including the patients indicated for long-term hemodialysis (HD) with an estimated GFR of less than 20 mm/min/1.73m². Following AVF surgery, post-operative outcomes, PF, and maturation time were considered. Results Among the 757 AVF procedures, 588 (82%) were new cases, and 112 (16%) had prior AVF history on the same side. PF was observed in 126 (18%) AVFs, while 574 (84%) achieved maturation. Age at surgery did not correlate with PF. Male sex and brachiocephalic AVF (BCAVF) had lower PF rates, while female gender, non-BCAVF, and vascular chronic kidney disease (CKD) were independent predictors. Proximal fistulas had a higher failure risk (32%). During surgery, the PF occurred six times more frequently in patients with veins and arteries under 2 mm and without a bruit. Conclusion AVF maturation aims to achieve a functional AVF for easy dialysis, requiring meticulous vein selection, doppler vascular mapping, and a standardized process to reduce PF rates. Factors determining PF include thrill and bruit, flow rates, and comorbidities. These findings can help clinicians make informed decisions and improve outcomes for patients undergoing fistula surgery.

Obesity drives secondary procedures to achieve access maturation in end-stage renal disease

BackgroundEstablishing long-term arteriovenous access is an important component in the long-term care of a patient with end-stage renal disease. The increasing frequency of obesity is reported to impact the access management of end-stage renal disease patients. This study aims to evaluate the outcomes of arteriovenous fistulae (AVF) in obese and nonobese patients. MethodsA retrospective review of all patients over ten years with primary autogenous AVF (radiocephalic, brachiocephalic, and brachial-basilic) was undertaken at a single center. Patients were subcategorized by body mass index into nonobese, class I, II, and III obesity. Outcomes of maturation (successful progression to hemodialysis), reintervention, functional dialysis (continuous hemodialysis for 3 consecutive months), and patency were examined. ResultsFrom January 1999 to December 2019, 2311 patients (67% female; mean age, 61 ± 15 years) underwent primary AVF placement (12% radiocephalic, 53% brachiocephalic, and 35% brachial basilic). Forty-one percent were nonobese, 29% had class I obesity, 19% had class II obesity, and 11% had class III obesity. The majority of patients were diabetic and Hispanic. The 30-day major adverse cardiovascular event rate was elevated in class II (0.20%) and class III (0.50%) obesity compared with class I obesity (0.15%) and nonobese (0.05%). The 30-day morbidity rate was higher in all classes of obesity (0.5% vs0.3% vs 0.2% vs 0.05% for class III vs class II vs class I obesity and nonobese, respectively). Early thrombosis was significantly increased in class II (9%) and class III obesity (12%) compared with class I obesity (5%) and nonobese (3%). There was a two-fold increase in procedures to effect maturation in class II (51%) and class III (74%) obesity compared with class I obesity (22%) and nonobese (34%). Secondary patency at 3 years was significantly lower in class III (62 ± 4%) and class II (79 ± 3%) compared with class I obesity (87 ± 2%) and nonobese (93 ± 4%). All classes of obesity required significantly more secondary Interventions per year compared with nonobese (3.9 vs 3.1 vs 2.5 vs 1.4 secondary interventions per year for class III vs class II vs class I obesity and nonobese, respectively). ConclusionsAdvancing obesity class is associated with an increased number of procedures to achieve AVF maturation and is associated with poorer patency and functionality as the category of obesity advances.

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.

Long-term patency of arteriovenous fistulas for hemodialysis: A decade's experience in a transplant unit.

The heterogeneous quality of studies on arteriovenous fistulas outcome, with variable clinical settings and large variations in definitions of patency and failure rates, leads to frequent misinterpretations and overestimation of arteriovenous fistula patency. Hence, this study aimed to provide realistic and clinically relevant long-term arteriovenous fistula outcomes. We retrospectively analyzed all autologous arteriovenous fistulas at our center over a 10-year period (2012-2022). Primary and secondary patency analysis was conducted using the Kaplan-Meier method; multivariate analysis of variance was used to detect outcome predictors. Vascular access-specific endpoints were defined according to the European guidelines on vascular access formation. Of 312 arteriovenous fistulas, 57.5% (n = 181) were radio-cephalic (RC_AVF), 35.2% (n = 111) brachio-cephalic (BC_AVF), and 6.3% (n = 20) brachio-basilic (BB_AVF). 6, 12, and 24 months follow-up was available in 290 (92.1%), 282 (89.5%), and 259 (82.2%) patients, respectively. Primary patency rates at 6, 12, and 24 months were 39.5%, 34.8%, and 27.2% for RC_AVF, 58.3%, 44.4%, and 27.8% for BC_AVF, and 40.0%, 42.1%, and 22.2% for BB_AVF (p = 0.15). Secondary patency rates at 6, 12, and 24 months were 65.7%, 63.8%, and 59.0% for RC_AVF, 77.7%, 72.0%, and 59.6% for BC_AVF, and 65.0%, 68.4%, and 61.1% for BB_AVF (p = 0.29). Factors associated with lower primary and secondary patency were hemodialysis at time of arteriovenous fistula formation (p = 0.037 and p = 0.024, respectively) and higher Charlson Comorbidity Index (p = 0.036 and p < 0.001, respectively). Previous kidney transplant showed inferior primary patency (p = 0.005); higher age inferior secondary patency (p < 0.001). Vascular access care remains challenging and salvage interventions are often needed to achieve maturation or maintain patency. Strict adherence to standardized outcome reporting in vascular access surgery paints a more realistic picture of arteriovenous fistula patency and enables reliable intercenter comparison.

Outcomes of arteriovenous graft vs. fistula for haemodialysis access in the elderly: A systematic review and meta‑analysis.

The impact of the type of vascular access on the outcomes in the elderly haemodialysis patients is still unclear. The goal of the present study was to compare survival outcomes in elderly haemodialysis patients who received either arteriovenous graft (AVG) or arteriovenous fistula (AVF). A systematic literature search was performed in EMBASE, Cochrane, MEDLINE, ScienceDirect and Google Scholar databases for papers published from January 1954 until January 2022. Risk of bias in the selected publications was assessed by Newcastle Ottawa scale or Cochrane risk of bias tool depending on the study design. Meta-analysis was carried out using the random-effects model. Data were reported as pooled odds ratio (OR) or hazard ratio (HR) with 95% confidence interval (CI). A total of 12 studies were included in the analysis. The majority of the studies had poor quality. Elderly patients receiving AVG had significantly worse survival rate compared with patients that received AVF for the haemodialysis access, with a pooled HR of 1.38 (95% CI, 1.24-1.53; I2=79.9%). Pooled HR for access survival was 1.60 (95% CI, 1.54-1.66; I2=0%). Pooled OR for primary patency rate, maturation failure and infections were 1.81 (95% CI, 0.73-4.49; I2=79.2%), 0.33 (95% CI, 0.12-0.91; I2=70.4%) and 9.74 (95% CI, 2.60-36.49; I2=52.4%), respectively. These results suggested that in elderly patients undergoing haemodialysis, AVG was associated with reduced overall survival and access survival, and higher infection rate, compared with AVF. Notably, AVG was also associated with a lower risk of maturation failure, presenting a potential advantage in specific patient populations (study registration: PROSPERO, no. CRD42022313199).

Comparison of wound complications between one-stage and two-stage brachiobasilic arteriovenous fistula: A meta-analysis.

Research assessing the outcome of brachiobasilic arteriovenous fistulas (BB-AVF) after a one- and two-stage technique was conducted. A strict review of the comprehensive literature up to May 2023 was carried out using four databases-PubMed，Embase, Cochrane Library and web of science. Inclusion and exclusion criteria developed for the study were then applied to assess the quality of the literature, it was decided to review 12 interrelated studies.95% confidence intervals (Cl) and odds ratios (OR) were calculated using fixed effects models. The data were meta-analysed using RevMan 5.3 software. The results showed that two-stage technique with BB-AVF reduced surgical site haematoma (SSH) formation, (OR, 2.28; 95% CI, 1.24-4.17, p = 0.008), and also reduced surgical site wound infection (SSWI) (OR, 1.86; 95% CI, 1.17-2.94, p = 0.008). There are, however, several small sample sizes in the selected studies for this meta-analysis, so caution should be used when processing their values. There are more high-quality studies with large sample sizes that should be considered for future meta-analyses.

Management and Outcome of Intracranial Dural Arteriovenous Fistulas That Have Caused a Hemorrhage in the Posterior Fossa : A Clinical Study.

We evaluated the diagnosis, treatment, and long-term results of patients with dural arteriovenous fistula (dAVF), which is a very rare cause of posterior fossa hemorrhage. This study included 15 patients who underwent endovascular, surgical, combined, or Gamma Knife treatments between 2012 and 2020. Demographics and clinical features, angiographic features, treatment modalities, and outcomes were analyzed. The mean age of the patients was 40 ± 17 (range 17-68), and 68% were men (11/15). Seven of the patients (46.6%) were in the age group of 50 years and older. While the mean Glasgow Coma Scale was 11.5 ± 3.9 (range 4-15), 46.3% presented with headache, and 53.7% had stupor/coma. Four (26.6%) patients had only cerebellar hematoma and headache. All dAVFs had cortical venous drainage. In 11 (73.3%) patients, the fistula was located in the tentorium and was the most common localization. Three (20%) patients had transverse and sigmoid sinus localizations, while one (6.7%) patient had dAVF located in the foramen magnum. Eighteen sessions were performed on the patients during endovascular treatment. Sixteen (88.8%) sessions were performed with the transarterial (TA) route, one (5.5%) session with the transvenous (TV) route, and one (5.5%) session with the TA + TV route. Surgery was performed in two (14.2%) patients. One (7.1%) patient passed away. While there were nine (64.2%) patients with a Rankin score between 0 and 2, the total closure rate was 69.2% in the first year of control angiograms. In the differential diagnosis of posterior fossa hemorrhages, the differential diagnosis of dAVFs, which is a very rare entity, should be considered, even in the middle and elderly age groups, in patients presenting with good clinical status and pure hematoma. The treatment of such patients can be done safely and effectively in a multidisciplinary manner with a good understanding of pathological vascular anatomy and appropriate endovascular treatment approaches.

Sex Disparities in Arteriovenous Fistula Maturation Outcomes

The end-stage kidney disease life-plan aims to individualize hemodialysis (HD) access selection in patients requiring renal replacement therapy. Paucity of data on risk factors for poor arteriovenous fistula (AVF) outcomes limits the ability of physicians to guide their patients on this decision. This is especially true for female patients, who are known to have worse AVF outcomes when compared to male patients. The goal of this study was to identify risk factors associated with poor AVF maturation outcomes in female patients that will help guide individualized access selection. A retrospective review of 1,077 patients that had AVF creation between 2014 and 2021 at an academic medical center was performed. Maturation outcomes were compared between 596 male and 481 female patients. Separate multivariate logistic regression models were created for the male and female cohorts to identify factors associated with unassisted maturation. AVF was considered mature if it was successfully used for HD for 4-week sessions without need for further interventions. Unassisted fistula was defined as an AVF that matured without any interventions. The male patients were more likely to receive more distal HD access; 378 (63%) male versus 244 (51%) female patients had radiocephalic AVF, P<0.001. Maturation outcomes were significantly worse in female patients; 387 (80%) AVFs matured in females and 519 (87%) in male patients, P<0.001. Similarly, the rate of unassisted maturation was 26% (125) in female patients versus 39% (233) in male patients, P<0.001. Mean preoperative vein diameters were similar in both groups; 2.8±1.1mm in male versus 2.7±0.97mm in female patients, P=0.17. Multivariate logistic regression analysis of the female patients revealed that Black race (odds ratio [OR]: 0.6, 95% confidence interval [CI]: 0.4-0.9, P=0.045), radiocephalic AVF (OR: 0.6, 95% CI: 0.4-0.9, P=0.045), and preoperative vein diameter <2.5mm (OR: 1.4, 95% CI: 10.33-0.901.1-1.7, P=0.014) were independent predictors of poor unassisted maturation in this cohort. In male patients, preoperative vein diameter <2.5mm (OR: 1.4, 95% CI: 1.2-1.7, P<0.001) and need for HD prior to AVF creation (OR: 0.6, 95% CI: 0.3-0.9, P=0.018) were independent predictors of poor unassisted maturation. Black women with marginal forearm veins may have worse maturation outcomes, and upper arm HD access should be considered when advising patients on their end-stage kidney disease life-plan.

Clinical features, treatment strategies and outcomes of craniocervical junction arteriovenous fistulas: a cohort study of 193 patients

BackgroundCraniocervical junction (CCJ) arteriovenous fistulas (AVFs) are rare. The current treatment strategies for AVFs with different angioarchitecture need to be clarified. The present study aimed to analyse the correlation between...

The VEBAS score: a practical scoring system for intracranial dural arteriovenous fistula obliteration

BackgroundTools predicting intracranial dural arteriovenous fistulas (dAVFs) treatment outcomes remain scarce. This study aimed to use a multicenter database comprising more than 1000 dAVFs to develop a practical scoring system...

Analysis of clinical outcomes of arteriovenous fistula for hemodialysis access in a Mexican elderly population.

The increased survival rates of end-stage renal disease (ESRD) patients have impacted directly in the proportion of elderly patients requiring a reliable hemodialysis (HD) access; this group clearly demands an individualized approach. We aim to analyze maturation and patency rates of arteriovenous fistulas (AVF) in elderly patients. This was retrospective review of a database of patients that underwent AVF creation in our institution. The maturation and patency rates were analyzed divided in groups based on age (equal and greater of 65 years, and patients under 65 years). Patency rates were compared using Kaplan-Meier analysis. Twenty patients ≥ 65 years old (mean 73, SD ± 5.4) were analyzed. The overall maturation rate in this group was 75% compared to 84.1% (p = 0.33) in the younger group (mean age 48 years, SD ± 17). The primary patency at 6 and 12 months for the ≥ 65 years group was 93% and 86%, respectively, compared with 85% and 81% for the younger group (p = 0.77). Autogenous AVF remains the preferred and durable option for elderly patients. We found no difference in terms of maturation and patency rates compared to younger patients. Standardized protocols are needed to optimally select vascular accesses.

483 Partial Treatment as a Risk Factor in Up-Conversion of Type 1 dAVFs

INTRODUCTION: Type 1 dural arteriovenous fistulas (dAVFs) lack cortical venous drainage and occasionally necessitate intervention depending on patient symptoms. Up-conversion is the rare transformation of a dAVF to a higher-grade. Causes for up-conversion are unknown. We tested the hypothesis whether partial treatment of type 1 dAVFs increases their likelihood of up-conversion. METHODS: We used the multicenter Consortium for Dural Arteriovenous Fistula Outcomes Research (CONDOR) database to perform a retrospective analysis of all patients with type 1 dAVFs. Propensity score analysis was utilized to determine if partial treatment was an independent risk factor for up-conversion. A regression model identified secondary risks that contributed to up-conversion. RESULTS: 358 out of 1077 patients within the consortium had type 1 dAVFs. 12% of patients who were partially treated for a type 1 dAVF experienced an up-conversion, while less than 1% of patients who received no treatment experienced up-conversion, and 0% of patients who had a complete treatment of their dAVF experienced up-conversion. Higher proportions of tinnitus, bruits, and intracranial hemorrhage at initial presentation were found in patients who up-converted. The majority of up-converted dAVFs were located in the transverse-sigmoid sinus and all received embolization as part of their treatment. CONCLUSIONS: Partial treatment is an independent risk factor for up-conversion when compared to no treatment or complete treatment. In the partial treatment group, hemorrhage at inital presentation and use of embolization as a treament modality are factors that increase risk for up-conversion.

Functional patency rates of arteriovenous fistula of a retrospective cohort study from one of thebiggest centers in Canada.

The main barriers to arterio-venous fistula (AVF) utilization are primary failure, long maturation duration, and low secondary patency rates. In this retrospective cohort study, primary, secondary, functional primary, and functional secondary patency rates were calculated and compared between two age groups (< 75years and > = 75years) and between radiocephalic (RC-) and upper arm (UA-) AVFs, and factors determining the duration of functional secondary patency were evaluated. Between 2016 and 2020,206 predialysis patients whose AVFs had been created previously initiated renal replacement treatment. RC-AVFs comprised 23.3% and were created after favorable analysis of the forearm vasculature. Overall, the primary failure rate was 8.3, and 84.7% started hemodialysis with a functioning AVF. Functional secondary patency rates of primary AVFs were better with RC-AVFs [1,3 and 5year rates of 95.8, 81.9 and 81.9% versus 83.4, 71.8 and 59.2% for UA-AVFs (log rankp: 0.041)]. There was no difference between the two age groups for any of the AVF outcomes assessed. Among patients whose AVF was abandoned, 40.3% had gone on to have a second fistula created. This was significantly less likely in the older group (p < 0.01). (1) UA-AVFs were placed more commonly than RC-AVFs; (2) a selection bias existed whereby RC-AVFs were only created after favorable forearm vasculature was demonstrated or suspected; (3) superior functional secondary patency rates were observed with RC-AV's, perhaps stemming from this selection bias; (4) the elderly were more likely to have only one AVF creation attempt.

Comparing post-maturation outcomes of arteriovenous grafts and fistulae.

Though arteriovenous grafts (AVG) mature more reliably than arteriovenous fistulae (AVF) and require fewer maturation procedures (MP) to obtain functional patency, AVG are thought to have worse function after maturation. We explored differences in post-maturation outcomes between the following groups: AVF patients who did (AS-AVF) and did not (unAS-AVF) require assisted maturation and AVG patients who did (AS-AVG) and did not (unAS-AVG) require assisted maturation. Using the US Renal Data System (2012-2017), we retrospectively identified patients who initiated dialysis with a central venous catheter, underwent AVF or AVG placement and achieved successful two-needle cannulation. Primary patency and access abandonment after maturation were compared across groups using competing risks regression methods, generating sub-hazards ratios (sHR). We identified 42,664 AVF and 12,335 AVG that met inclusion criteria. A larger proportion of AVFs required interventions: 18,408 AVF (43.2%) versus 2594 AVG (21.0%; p < 0.01). Both AS-AVG and AS-AVF patients experienced patency loss at 1 year more frequently compared with unAS-AVG (67.5% & 57.5% vs 55.2% respectively). Patency loss was lowest in unAS-AVF (38.9%). These trends were robust on adjusted analysis (unAS-AVG reference, AS-AVG sHR = 1.44, p < 0.01; AS-AVF sHR = 1.08, p < 0.01, unAS-AVF sHR = 0.67, p < 0.01). AS-AVGs were more likely to be abandoned than unAS-AVGs (11.7% unAS-AVG vs 17.2% AS-AVG). Fistulae, assisted or not, had lower unadjusted rates of 1-year abandonment than grafts (8.9% AS-AVF vs 7.3% unAS-AVF). On adjusted analysis, AVF usage was protective against abandonment (unAS-AVG, reference; AS-AVF sHR = 0.67, p < 0.01; unAS-AVF sHR = 0.59, p < 0.01) while AS-AVG was not (AS-AVG sHR = 1.32, p < 0.01). unAS-AVF have the best long-term outcomes. AS-AVF lose primary patency at a higher rate than unAS-AVG. AVGs may be a better choice than AVFs if veins are marginal and likely to require assisted maturation. Further research is needed to identify anatomic and physiologic factors that affect long-term performance and influence conduit choice.

Systematic review and meta-analysis of preoperative interventions to support the maturation of arteriovenous fistulae in patients with advanced kidney disease.

There is great potential to improve outcomes of arteriovenous fistulas (AVFs) by focusing more on the preoperative period of AVF creation. We aim to systematically review the evidence on safety and efficacy of various preoperative interventions that have been tried to improve AVF maturation and success rate. We searched five databases: PubMed, Embase, CINAHL, Cochrane Library and King's Fund Library. Experimental studies that investigated the effect of various preoperative interventions to improve AVF outcomes among advanced chronic kidney disease (CKD) patients were searched. The effect size for primary outcome was calculated as the weighted mean difference in the final vessel calibre, rate of AVF maturation or primary failure between the intervention and control arm. We also assessed adverse effects and dropout rates. This review was preregistered in the International Prospective Register of Systematic Reviews (CRD42020193257). Eight eligible studies were identified involving three types of intervention: hand exercise (n=6), cholecalciferol supplementation (n=1) and pneumatic compression of the arm using a Fist Assist device (n=1). The overall effect size of hand exercise on distal cephalic vein calibre was 0.24mm [95% confidence interval (CI) 0.03-0.45] on meta-analysis of hand exercise studies. On restricting analysis to two randomized controlled trials (RCTs) that had independent control groups, the effect size was higher, at 0.29mm (95% CI 0.11-0.47). Hand exercise was a well-tolerated intervention, especially when confined to the first 4weeks. Hand exercise is the predominant intervention tried in the preoperative period of AVF creation, although there is methodological heterogeneity. Intermittent pneumatic compression using a Fist Assist device is a novel intervention that has shown some promise. Well-designed prospective RCTs are needed on preoperative interventions among advanced CKD patients, aimed at improving AVF outcomes.

Editor's Choice – Interventions to Achieve Functionality in Newly Created Arteriovenous Fistulas in the Shunt Simulation Study Cohort

Although observational cohort studies report that interventions to achieve functionality are clinically successful in 85% of patients, the proportion of newly created autologous arteriovenous fistulas that result in functional vascular access typically is only 70 - 80%. To address this discrepancy, the selection and outcomes of interventions to achieve functionality in a multicentre prospective cohort study were analysed. The Shunt Simulation Study enrolled 222 patients who needed a first arteriovenous fistula in nine dialysis units in The Netherlands from 2015 to 2018 and followed these patients until one year after access creation. In this observational study, the technical and clinical success rates of interventions to achieve functionality based on lesion and intervention characteristics were analysed and the clinical outcomes of arteriovenous fistulas with assisted and unassisted functionality were compared. For patients who were on dialysis treatment at the end of the study, unassisted fistula functionality was 54% and overall fistula functionality was 78%. Thirty-four per cent of arteriovenous fistulas required an intervention to achieve functionality, 68% of which eventually became functional. Seventy-five per cent of these interventions were percutaneous balloon angioplasties of vascular access stenoses. Patients with clinically successful interventions to achieve functionality had larger pre-operative vein diameters (2.8 ± 1.0 mm vs. 2.3 ± 0.6 mm, p= .036) and less often presented with thrombosed fistulas than patients with unsuccessful interventions (7% vs. 43%, p= .006). Arteriovenous fistulas with assisted functionality had similar secondary patency as fistulas with unassisted functionality (100% and 98% at six months, p= .44), although they required more interventions to maintain function (2.6 vs. 1.7 per year; rate ratio 1.52, 95% CI 1.04 - 2.18, p= .032). Interventions to achieve functionality were needed in about a third of newly created arteriovenous fistulas. Most thrombosed fistulas were abandoned, and when selected for thrombectomy rarely reached clinical success. On the other hand, interventions to achieve functionality of patent fistulas had high clinical success rates and therefore can be done repeatedly until the fistula has become functional.

A decade of arteriovenous fistula creations in the ⩾75 years population: Equal opportunity or sub-optimal use of resources.

The optimal vascular access in the elderly remains contentious in the context of increasingly limited resources and anticipated survival on hemodialysis. Research focus has shifted to include the impact of vascular access on quality of life. This study explored clinical outcomes in individuals aged ⩾75 years who had an arteriovenous fistula (AVF) created in a single center over a 10-year period. Demographic and clinical data concerning AVFs created January 2009-December 2019 were identified from a prospective database for retrospective analysis. Outcome measures were AVF patency and failure to mature rates plus overall patient and vascular access survival. The Vascular Access Specific Quality of life measure (VASQoL) was completed in a contemporary cohort aged ⩾75 years established on HD in October 2021. AVF outcomes were available for 272 patients (93%). The failure to mature (FTM) rate was 36% with the significant predictors of AVF FTM being the creation of a radiocephalic AVF (OR 8.13, 95% CI 8.02-8.52, p < 0.01), female gender (OR 4.84, 95% CI 4.70-5.41, p < 0.01), and a history of peripheral vascular disease (OR 5.25, 95% CI 5.22-6.00, p value = 0.02). Functional patency was associated with a median 12-month survival benefit compared to those whose fistula FTM (p < 0.01). The median patency duration for a functionally patent AVF was 3 years. Elderly patients with a fistula reported a lower quality of life in VASQoL scoring than those with central venous catheters. In this cohort, AVF creation in individuals aged ⩾75 years AVFs was associated with comparable AVF patency rates to younger patients. AVF functional patency was associated with superior patient survival compared to those with AVF FTM. A multi-disciplinary surveillance program may help reduce AVF loss. Further work on how vascular access choice impacts quality of life in elderly patients is required.

Profile of Arteriovenous Fistula Surgery in Patients with Chronic Kidney Disease at a Tertiary Care Urology Hospital Karnataka, India: A Prospective Interventional Study

Introduction: Haemodialysis (HD) is the most important treatment approach in patients with Chronic Kidney Disease (CKD), awaiting kidney transplantation, demanding the longterm need for dialysis access. Aim: To study the profile of Arteriovenous Fistula (AVF) surgery in patients undergoing haemodialysis in the Karnataka region, India. Materials and Methods: This prospective, interventional singlecentre study was conducted at the Institute of Nephrology and Urology, KR Hospital Campus, Mysuru, India, from April 2018 to April 2021. All the patients undergoing haemodialysis with AVF aged between 11-90 years were included. Demographic details (age, sex, co-morbidities) and fistula-related complications associated with surgery were examined in the immediate, late, and delayed postoperative period. Categorical variables were presented as numbers and percentages whereas, continuous variables were expressed as mean {Standard Deviation (SD)}. The data was collected in Excel Sheet and the statistical analysis was performed using Statistical Package for Social Sciences (SPSS), version 20.0. Results: In total, 200 patients with a mean (SD) age of 48.8 (13.0) years underwent AVF formation and the majority were below &lt;60 years of age (n=154, 77.0%). The incidence of fistula surgery and patency rates was higher in men (n=140, 70.0%). Most patients had left non dominant arm (n=187, 93.5%) and remaining right non dominant arm (n=13, 6.5%). The most common site of AVF was left brachial cephalic (n=135, 67.5%). The most common cause of CKD was diabetes mellitus (n=90, 45.0%). The most common immediately observed complications were bleeding (n=13, 6.5%), pain (n=12, 6.0%) and oedematous limb (n=5, 5.0%). Stitch abscess was the most common late complication observed in 14 patients (7%). Rupture of the aneurysm and AVF failure were delayed complications observed in eight (1.5%) and 17 (8.5%) patients, respectively. Conclusion: In this study, bleeding, stitch abscess and AVF failure were found to be the most common immediate, late, and delayed postoperative complications, respectively. However, more studies are required to understand the outcome of AVF in Chronic Renal Failure (CRF) patients from India.