Underwent Arteriovenous Fistula Creation Research Articles

#1922 Patterns and 2-year outcomes of preemptive vascular access creation in France

Abstract Background and Aims Most studies on clinical practices regarding the type and the timing of vascular access creation are limited to patients on kidney replacement therapy (KRT) from North American settings. Our aim was to describe patterns of preemptive vascular access creation in patients under nephrology care in France, and to assess the subsequent risks of hemodialysis (HD) initiation with arteriovenous (AV) access use, HD initiation with central venous catheter (CVC) use, initiation of other KRT modality, and competing death. Method From 2013 through 2016, the CKD-REIN cohort included 3033 adult patients with CKD stages 3 to 5 from 40 outpatient nephrology clinics in France, nationally representative geographically and in terms of facility legal status (public, private not for profit, and private for profit). Participants were followed for 5 years or until initiation of kidney replacement therapy (KRT) or death, whichever came first. Patients who underwent a first vascular access creation during follow-up were eligible for this analysis. We described the type, anatomical site and timing of the first vascular access created, as well as patients’ associated characteristics. The number and type of subsequent accesses were also described. Among patients who underwent AV fistula creation first, we used the cumulative incidence functions to estimate the 2-year probabilities of HD initiation with AV access use (independently of its type or order), HD initiation with CVC use, initiation of other KRT modality, and death. Results Over a median follow-up of 5.0 years (interquartile range [IQR], 4.6 to 5.2), 535 patients (18% of the total population) underwent a first vascular access creation. 408 patients (75%) had an AV fistula as their first vascular access, 7 patients (1%), an AV graft, and 127 patients (24%), a CVC. AV fistulas were predominantly located in the lower arm (76%). The median eGFR levels at access creation were 13 (IQR, 10 to 16), 12 (10 to 14) and 9 (6 to 13) ml/min/1.73 m2 for AV fistula, AV graft, and CVC, respectively. Groups defined by their first vascular access did not differ with regards to diabetes status, but patients who received AV fistula as their first vascular access stood out for being younger and having less cardiovascular comorbidities than their counterparts who received AV graft or CVC (Table 1). In contrast to the 7 patients with first AV graft who did not have any subsequent access creation, 22% of those with first AV fistula had at least one subsequent access creation before initiating KRT. The subsequent access was a fistula in 49% of cases (54% of them in the lower arm), a CVC in 48% and a graft in 2%. The 2-year cumulative incidences of HD initiation with AV access use, HD initiation with CVC use, preemptive kidney transplantation and pre-KRT death were 61%, 14%, 2% and 5%, respectively (Fig. 1); 18% of patients undergoing a first AV fistula creation did not experience any event within two years, and 25% did not start HD. No patients received peritoneal dialysis as other KRT modality. Conclusion In this nationwide description of patterns of preemptive vascular access creation, we highlight that lower arm AV fistula is largely prioritized, even after a first failed AV fistula creation. This may contribute to the higher use of AV fistula among HD patients in France compared to North American countries. Most patients who undergo a first AV fistula creation eventually start hemodialysis with an AV access within 2 years of this creation, but 1 out of 4 do not start HD at all (because of death, preemptive transplantation, or stable kidney function). Novel tools assisting clinical decision making in preemptive AV fistula creation are needed.

Incidental AVF creation during unrelated hospitalization is associated with worse outcomes compared with outpatient AVF creation.

Arteriovenous fistula (AVF) creation during an inpatient hospitalization is often performed for patient convenience and to ensure compliance. We sought to evaluate whether this approach has comparable outcomes to outpatient AVF creation. We identified patients undergoing index AVF creation from the United States Renal Data System dataset (2012-2017). Patients were grouped into outpatient and inpatient. Outpatient included patients that were operated in either an outpatient setting, ambulatory surgical center or were admitted inpatient on the day of AVF creation. Inpatient included only patients with claims for an inpatient visit before access creation. Multiple safety outcomes were compared between groups using unadjusted and adjusted logistic regression methods generating odds ratios and 95% confidence intervals (95% CI). One-year maturation rates were compared using competing-risks regression methods generating sub-hazard ratios (sHR) and 95% CI. Outcomes were also compared after 1:1 propensity score matching. We identified 68,872 patients undergoing AVF creation, 4855 (7.1%) of which were created during inpatient hospitalization. Patients in the inpatient group were older (65.8 ± 13.8 vs 65.2 ± 13.8, p = 0.002), more likely to be of Black race (28.1% vs 26.8%, p = 0.02), and have cardiovascular comorbidities (all p < 0.05). Patients in the inpatient groups were more likely to be dialyzed at for-profit (88.1% vs 85.9%, p < 0.01) and freestanding (94.8% vs 92.9%, p < 0.01) dialysis centers. On both unadjusted and adjusted analysis, inpatient group was more likely to experience 30-day adverse events (e.g. pneumonia, COPD exacerbation, stroke, myocardial infarction), any complication, and all-cause mortality. On competing risks analysis, successful two-needle cannulation at 1 year was significantly less likely in the inpatient group (68.1% vs 76.8%, p < 0.01; sHR = 0.68 [95% CI, 0.65-0.71], p < 0.01). These trends were robust on 1:1 propensity matching. Incidental AVF creation in hospitalized patients is associated with worse outcomes, ranging from mortality to postoperative complications to fistula maturation, compared with outpatient AVF creation.

Association of race and ethnicity with initial surgical hemodialysis access type in a safety net system

ObjectivesPrior studies have found lower arteriovenous fistula (AVF) creation rates in Black and Hispanic patients. Whether this is due to health care disparities or other differences is unclear. Our objective was to evaluate the racial/ethnic differences in initial surgical access type within a high-volume, safety net system with predominantly Black and Hispanic populations. MethodsA retrospective review of initial hemodialysis (HD) access in consecutive cases between 2014 and 2019 was conducted from all five safety net hospitals in a health care system that primarily treats underserved patients. Patient data collected included race, ethnicity, sex, comorbidities, and initial arteriovenous (AV) access type (AV fistula [AVF] vs AV graft [AVG]). The rates of cephalic vein-based AVF (CAVF; radiocephalic, brachiocephalic) were compared with basilic and brachial vein AVF (BAVF), because the latter are performed as two stages. Bivariate and multivariate logistic regression models were adjusted for demographic and clinical variables to evaluate the relationship between race/ethnicity, surgical access type, and comorbid conditions. ResultsWe included 1334 patients (74% Hispanic, 9% Black, 7% Asian, 2% White, 8% other) who underwent first-time surgical HD access creation. The majority were male (818 [63%]). Medical comorbidities were equal among groups, except for chronic obstructive pulmonary disease and stroke, which were higher in Black patients (P < .005 and P = .005, respectively). Overall, 1303 patients (98%) underwent AVF creation and 31 AVG creation (2%), with no difference between race/ethnicity in AVF vs AVG creation. Of the AVF cohort, 991 (76%) had a CAVF and 312 (24%) had a BAVF. Males were more likely than females to get a CAVF (65% vs 35%; P = .002). ConclusionsWithin our safety net health system, where most patients are under-represented minorities, nearly all patients undergoing HD access had an AVF as their initial surgery with no difference in race/ethnicity. AVF type received differed by race, with Black patients twice as likely to undergo BAVF, which required two stages. Further studies are needed to identify the reasons for these differences.

The feasibility of small-caliber veins for autogenous arteriovenous fistula creation: A single-center retrospective study.

Autogenous arteriovenous fistula (AVF) is recommended as the first choice for hemodialysis vascular access. A small-caliber vein is one of the independent risk factors for AVF maturation and patency. However, the specific threshold is still unclear, making it difficult to accurately determine whether these vessels are suitable for AVF creation. This is a single-center retrospective study. Patients who underwent AVF creation in our medical center between January 2020 and September 2022 and satisfied the eligibility criteria were included in this retrospective study. Logistic regression analysis was performed to identify risk factors for functional maturation and additional intervention. The optimal cutoff value was determined based on the receiver operating curve (ROC) and the Youden index. Kaplan-Meier analysis was utilized in further patency rate comparisons. A total of 125 forearm AVFs were created in 121 patients with end-stage renal disease (ESRD). The mean age was 53.88 ± 15.10 years. Preoperative vascular Doppler ultrasound (DUS) was conducted and recorded in 106 cases (84.80%). The mean targeted artery and vein diameters were 2.17 ± 0.54 and 1.71 ± 0.75 mm, respectively. Small-caliber vein is the risk factor for functional maturation failure (OR = 0.256, 95%CI [0.06-0.75], p = 0.033) and additional intervention (OR = 0.306, 95% CI [0.09-0.78], p = 0.031). The optimal cutoff value is 1.35 mm (augmented) when specificity and sensitivity reach 80 and 63.7%, respectively. The AVFs with a vein diameter of more than 1.35 mm (augmented) showed higher patency rates (p < 0.01). After comprehensive DUS evaluation, intraoperative hydrodilation, postoperative active exercise and intensive DUS detection, and application of balloon-assisted maturation, if necessary, using a vein more than 1.35 mm (augmented), could achieve satisfactory functional maturation and postoperative patency in AVF formation.

Association of Shear Stress with Subsequent Lumen Remodeling in Hemodialysis Arteriovenous Fistulas.

Blood flow-induced wall shear stress is a strong local regulator of vascular remodeling, but its effects on arteriovenous fistula (AVF) remodeling are unclear. In this prospective cohort study, we used computational fluid dynamics simulations and statistical mixed-effects modeling to investigate the associations between wall shear stress and AVF remodeling in 120 participants undergoing AVF creation surgery. Postoperative magnetic resonance imaging data at 1 day, 6 weeks, and 6 months were used to derive current wall shear stress by computational fluid dynamic simulations and to quantify subsequent changes in AVF lumen cross-sectional area at 1-mm intervals along the proximal artery and AVF vein. Combining artery and vein data, prior mean wall shear stress was significantly associated with lumen area expansion. Mean wall shear stress at day 1 was significantly associated with change in lumen area from day 1 to week 6 (11% larger area per interquartile range [IQR] higher mean wall shear stress, 95% confidence interval [95% CI], 5% to 18%; n =101), and mean wall shear stress at 6 weeks was significantly associated with change in lumen area from 6 weeks to month 6 (14% larger area per IQR higher, 95% CI, 3% to 28%; n =52). The association of mean wall shear stress at day 1 with lumen area expansion from day 1 to week 6 differed significantly by diabetes ( P =0.009): 27% (95% CI, 17% to 37%) larger area per IQR higher mean wall shear stress without diabetes and 9% (95% CI, -1% to 19%) with diabetes. Oscillatory shear index at day 1 was significantly associated with change in lumen area from day 1 to week 6 (5% smaller area per IQR higher oscillatory shear index, 95% CI, 3% to 7%), and oscillatory shear index at 6 weeks was significantly associated with change in lumen from 6 weeks to month 6 (7% smaller area per IQR higher oscillatory shear index, 95% CI, 2% to 11%). Wall shear stress spatial gradient was not significantly associated with subsequent remodeling. In a joint model, wall shear stress and oscillatory shear index statistically significantly interacted in their associations with lumen area expansion in a complex nonlinear fashion. Higher wall shear stress and lower oscillatory shear index were associated with greater lumen expansion after AVF creation surgery.

Echocardiographic changes after arteriovenous fistula creation in hemodialysis patients.

Pulmonary hypertension (PH) is common in end-stage renal disease (ESRD) patients and is associated with increased all-cause and cardiovascular mortality in this group. There is scarce data on the long-term effect of arteriovenous fistula (AVF) creation on pulmonary hypertension (PH) and the reflected changes in echocardiographic measurements. This is a retrospective study of 54 patients who underwent AVF creation between 2009 and 2014 and with echocardiographic evaluations before and after surgery. We analyzed pairwise changes in right ventricular systolic pressure (RVSP), right atrial pressure (RAP) during systole, left ventricular mass (LVM), tricuspid regurgitation (TR), mitral E/E' ratio, and ejection fraction (EF), as well as the factors that predicted change in RVSP after surgery. The median time for the preoperative echocardiogram was 0.3 years (interquartile range (IQR) 0.2-0.7 years) prior to AVF creation, while the follow-up echo was done 1.3 (0.6-2.1) years after surgery. 67% of the patients had RVSP&gt;37 mmHg at baseline. There was a significant reduction in RVSP after AVF creation compared to baseline (median 33 (IQR 26-43) vs. 46mmHg, p=0.0015), with 59% of the patients experiencing a decrease and 19% remaining stable. There were also significant decreases in LVM (201 (143-256) vs. 215 (163-276), p=0.045) and RAP systole (10 (10-15) vs. 3 (3-8); p&lt;0.001) after surgery. Higher preoperative weight (p=0.038) and RVSP (p=0.006), and use of loop diuretics (p=0.015) were significantly associated with improvement in RVSP after AVF creation. Our results suggest that AVF creation is associated with a significant reduction or stable measurements of RVSP in the ESRD population, likely due to an improvement in volume status.

Cost of arterioveinous fistula at the Douala General Hospital: A Cameroon-based cross-sectional study

Background: Cost is a major limiting factor for dialysis in low-income countries. The objective of our study was to determine the economic cost of creating an arteriovenous fistula (AVF) for hemodialysis at the Douala General Hospital (DGH). Material and methods: We conducted a descriptive cross-sectional study including patients undergoing AVF creation at the DGH from January to April 2020. Costs were calculated using a bottom-up approach. The direct cost was composed of the sum of the cost of medical consultation, additional paraclinical tests, drugs, disposables, hotel services, food, transport and medical and nursing care. The indirect cost was calculated as the sum of the costs related to the temporary incapacity to work and the additional expenses of the families. The cost of temporary work incapacity was calculated according to human capital theory. The economic cost was the sum of the direct cost and the indirect cost. The costs were expressed as a mean with standard deviation. The calculated costs were expressed in US Dollars. Statistical significance was considered as p &lt; 0.05. Results: A total of 44 patients were included of which 29/44 (65.9%) were male. The mean age of the study population was 49.1 ± 14.7 years. The median monthly income was $172 and only 6.8% of patients had health insurance. The average direct cost per patient was $327.3 ± $212.7, with hospitalization costs accounting for 59.6% of that cost. The average indirect cost per patient was $64.5 ± $50.3. The largest proportion of these costs was due to lost productivity related to temporary work disability (45.7%). The average economic cost per patient was $391.9 ± $219.5. Direct costs accounted for 83.54% of the economic cost. Re-operation (p = 0.039), age (p &lt; 0.01) and number of hospitalization days (p &lt; 0.01) significantly affected the cost Conclusion: The cost of creating an AVF for hemodialysis was high and represented more than 2 times the median monthly income of patients and was mainly due to hospitalization costs. Therefore, there is a need to implement strategies to reduce the financial burden of arteriovenous fistula creation in our setting.

Distally based V-flap on the artery in an end-to-side anastomosis for arteriovenous fistula creation – A randomized controlled pilot study

With an increasing number of chronic kidney disease (CKD) patients presenting at a young age, it is necessary to create a vascular access (VA) that is reliable, long-lasting, and has minimal complications. Despite improvements in anastomotic techniques, distal arteriovenous fistula (AVF) has a high failure rate. The successful use of a geometric design for the end-to-side anastomosis in free tissue transfer led us to consider whether V-flap technique can be employed to achieve consistent and earlier maturation in distal AVF and reduce the failure rates. This was a prospective randomized controlled trial conducted between January and April 2022. Twenty CKD patients were randomized into two groups and underwent AVF creation using the slit-arteriotomy and the V-flap technique. Postoperative follow-up was performed on the 1st, 2nd, 4th, 6th, and 8th weeks. Cross-sectional area (CSA) and circumference of vein, linear and volumetric flow across the anastomosis, and the time taken to achieve AVF maturation were analyzed. There was a significant increase in the CSA and circumference in the V-flap group as compared to that in the slit-arteriotomy group. The volumetric flow across the anastomosis in the V-flap group was significantly higher than that of the slit-arteriotomy group. The median time to achieve AVF maturation in the slit-arteriotomy group was 8 weeks, whereas it was 4 weeks in the V-flap group. The V-flap technique creates an anastomosis with a greater CSA facilitating larger volumetric flow rate. This helps to achieve a consistent, reliable, and earlier maturation with successful initiation of hemodialysis.

Pathophysiology of High Output Arteriovenous Fistula with Heart Failure: A Systematic Review and Meta-analysis

Introduction: Arteriovenous Fistula (AVF) is extensively used as vascular access for haemodialysis patients. It induces a high output state, which is associated with cardiac remodeling. With High Output Heart Failure (HOHF), the AVF occupies a low pressure; reduced vascular resistance and increased venous return. The High Output Arteriovenous Fistula with Heart Failure (HOHF-AVF) patients often undergo a comprehensive assessment of type of underlying diseases, the degree of vasodilatation along with laboratory investigations and cardiac imaging. Hence identification of the pathophysiological determinants of HOHF-AVF is intriguing. Aim: To identify the pathophysiological determinants of HOHF-AVF. Materials and Methods: This systematic review was conducted from May 2021 to December 2021 at the Department of Cardiovascular Surgery, Imperial College, United Kingdom. Randomised Controlled Trials (RCTs), cohort, case-control, cross-sectional and descriptive studies, conducted on adult patients who underwent AVF creation or ligation and addressed the pathophysiological determinants of HOHFAVF were included. Studies conducted among Paediatric cases, case reports, and case series were excluded. Medline (PubMed), EMBASE, ProQuest, and the Cochrane database were searched, by utilising the key words {[(“HOHF” OR “High output heart failure”) AND (“AVF” OR “Arteriovenous fistula”)] AND (“LV parameters” OR “Structural Characteristics” OR “Echocardiographic indices)}. The searches were restricted from January 2000 to October 2021 with studies published in the English language. All the included studies were subjected to critical appraisal using the “Cochrane risk of bias assessment tool” for RCTs, and the “Joanna Briggs Institute (JBI) checklist” for cohort, case-control, cross-sectional and descriptive studies. For meta-analysis Mantel-Haenszel Odds Ratio (M.H. O.R.) with its 95% Confidence Interval (C.I), Mean Difference (M.D) with its 95 % C.I were computed. The Review Manager Software (Rev Man 5, Cochrane collabouration, Oxford, England) was used for data analytics. Results: Overall, 115 citations were identified from the initial search, of which 29 studies were retrieved. Later, 14 studies were excluded. Of the remaining 15 studies, 12 were subjected to meta-analysis. There was a change in Left Ventricular (LV) end diastolic diameter (M.D=2.0; p&lt;0.001; 95% C.I=1.13 to 2.86), and cardiac index (M.D=0.63; p&lt;0.001, 95% C.I=0.46 to 0.79) from baseline to atleast three months of postsurgery among HOHF-AVF patients. According to the AVF flow, there was a change in LV systolic diameter (M.D=-18.90; p&lt;0.01; 95% C.I=-22.84 to-14.96), cardiac index (M.D=0.50; p=0.007; 95% C.I=0.14 to 0.86) and tricuspid annular plane systolic excursion (M.D=3.90; p=0.03; 95% C.I=0.30 to 7.50). Conclusion: Left ventricular end diastolic diameter and cardiac index were found to be the major determinants for a HOHFAVF. The left ventricular mass index, ejection fraction, posterior wall thickness, interventricular septum were not associated with HOHF-AVF. Left ventricular systolic diameter, cardiac index and tricuspid annular plane systolic excursion were the determinants of AVF flow.

Outcomes of arteriovenous fistula for hemodialysis in pediatric age group

IntroductionThe feasibility of arteriovenous fistula (AVF) creation in pediatric patients has long been documented, but few studies have evaluated the forms and long-term outcomes. The aim of this article is to highlight the types, techniques and outcomes of AVFs in pediatric age group. MethodsThis is multi-center, retrospective, single cohort study, including all the cases of pediatric (less than 18 year old) cases underwent AVF creation during four years (2015–2019). The following data were obtained from the patients' medical records and analyzed; socio-demographics, etiology of renal failure (RF), history of dialysis and transplantation, type and site of AVF, the outcomes and complications. ResultsThe study included 108 patients, 89 patients (82.4%) were female. The mean age was 13 years. The most common cause of RF was the urological causes which were found in 34 cases (31.5%), followed by nephrotic syndrome (32 cases, 29.6%), glomerulonephritis (27 cases, 25%), and polycystic kidney disease (12 cases, 11.1%). The decision for choosing access site was performed only by clinical examination in 96 patients (88.9%) while duplex ultrasound was requested for 12 cases (11.1%). The operation was done under local anesthesia in 81 cases (75%) and general anesthesia in 27 cases (25%). The procedure was performed in the wrist in 58 cases (53.7%) and in cubital fossa in 50 cases (46.2%). The most common early complication was hematoma (12 cases, 11.1%), followed by ecchymosis (10 cases, 9.3%), infection (8, 7.4%), seroma (4, 3.7%) and thrombosis (3, 2.8%). The one-year primary patency rate was found in 95 patients (88%) and two-year patency rate in 86 patients (79.6%). ConclusionNative AVF in pediatric is the first choice dialysis access even in pediatric population. Radiocephalic in the non-dominant hand is the most preferred site.

Evaluation of Factors Affecting Wrist Radio-Cephalic Arteriovenous Fistula Maturation: A Single Institutional Observational Study

Background: Chronic renal failure is the most common indication for which arterio-venous (AV) fistula creation surgery is being performed. Various studies have found that native arteriovenous fistulas are the best in long-term patency with lower complications. We conducted this study to find out the role of preprocedural duplex ultrasound (DUS) in predicting outcomes of radio-cephalic fistula in the wrist in the North-Karnataka population. Methods: This prospective study was conducted from May 2019 to July 2020 on 50 patients who were hemodialysis-dependent and underwent AV fistula creation with age from 20 to 70 years. All the patients underwent preoperative DUS and were followed up post-operatively after one, two, and six weeks. Hemodialysis was initiated through the constructed fistula once it was mature, and the maximum blood flow through the fistula was measured. SPSS version 20.0 was used for statistical analysis. Results: Among 50 subjects, the overall cumulative success of AVF maturation was 86% (43), and failure to mature rate was 14% (7). Logistic regression of maturation outcome in the wrist autologous arteriovenous fistula for individual factors showed statistically significant results (P &lt; 0.05) for the diameter of the radial artery &gt; 1.6 mm and the distensibility of the cephalic vein &gt; 0.4 mm. Conclusions: Vein distensibility and radial artery diameter are key factors in predicting successful AVF maturation. The use of intraoperative papaverine instillation directly on vessels can improve arteriovenous fistula outcomes.

Anticoagulation Therapy is Associated with Increased Access-related Wound Infections after Hemodialysis Access Creation

The effect of anticoagulation therapy (AC) on hemodialysis access patency and related complications is not well defined. Patients on long-term or chronic AC due to their underlying comorbid conditions may be particularly susceptible to access-related bleeding and complications from repetitive cannulation. Our goal is to assess the effect of anticoagulation therapy on outcomes after access creation. The Vascular Quality Initiative (VQI) database was queried for patients undergoing arteriovenous fistula (AVF) or graft (AVG) placement, from 2011 to 2019. Only patients with data on post-procedural AC status were included. Anticoagulation use was defined as patients on warfarin, dabigatran, or rivaroxaban after access creation at postoperative follow up. Demographic and procedural details were analyzed. Wound infection and patency rates at six months were assessed. Binomial logistic regression analysis was performed to assess the association of anticoagulation use with these outcomes. A total of 27,757 patients underwent access creation, with the majority undergoing AVF creation (78.8%). The average age was 61.4 years and 55.3% were male. 12.9% of patients were on postoperative AC. The wound infection rate was 2.3- 3.8% in the no AC and AC cohorts, respectively (P < 0.001). At six months follow-up, patency was 85.7- 84.3% in the no AC and AC cohorts, respectively (P=0.044). Expectedly, grafts had lower patency rates compared to AVF; those within the no AC cohort had a patency of 83.0% compared to 81.2 % in those on AC (P=0.106). On multivariable analysis, anticoagulation use was associated with a higher risk of wound infections (odds ratio [OR] 1.513, 95% confidence interval [CI] 1.160-1.973, P=0.002). AC use did not significantly affect access patency. Anticoagulation therapy was associated with a higher rate of wound infections but did not affect short-term access patency within six-months. These patients warrant close surveillance of their access for signs of infection. Furthermore, long-term implications of anticoagulation needs further evaluation.

A Comparative Study between Radiocephalic and Brachiocephalic Arteriovenous Fistula in End Stage Renal Disease

Background: Chronic Kidney Disease (CKD) is a major health issue all over the world. Patients with deteriorating renal function and end-stage renal disease require vascular access for hemodialysis. Studies suggest that Arterio-Venous fistula (AVF) constructed judiciously using autologous conduit give the best outcome in this regard. Objective of the study was to compare the outcomes of Radiocephalic and Brachiocephalic AVF in end stage renal disease (ESRD). Methods: It was a quasi-experimental study carried out at the Department of Vascular Surgery, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka. The study was conducted from June 2019 to May 2020. Patients suffering from ESRD underwent AVF creation surgery for hemodialysis access. A total of 60 (Sixty) patients were included in this study. The patients were divided into two groups; Group I included 30 patients who underwent Radiocephalic AVF operation and Group II included 30 patients who had Brachiocephalic AVF operation. Results: In Group I, (Radiocephalic AVF) 60% were male and 40% were female. On the other hand, in Group II (Brachiocephalic AVF) 73.3% were male and 26.7% were female. Calculated volume flow (Q max) was significantly higher in Group II compared with Group I (769.11±101.54 ml/min vs 626.37±55.81) ml/min) with the difference being statistically significant (P=0.001). Maturation time was significantly less in Group II compared with Group I )37.78±1.93 vs 43.33±2.12 days) with the difference between the two group being statistically significant (P=0.001). Complication was more in Group I than Group II (16.7% vs 3.3%). Conclusion: The present study shows that Brachiocephalic AVF gives significantly better outcome in terms of shorter maturation time and less complications compared with Radio-Cephalic AVF. Color Doppler study is an essential tool for preoperative vessel evaluation which guides the selection of suitable AVF construction site. Cardiovasc j 2021; 14(1): 44-49

Is Tunneled Cuffed Catheter a Viable Link to AV Fistula? An Experience from a Tertiary Care Centre

Introduction: The Tunneled Cuffed Catheter (TCC) is used as a bridge access for haemodialysis. Non-availability of fluoroscopy for insertion of TCC results in unnecessary waiting times and inappropriate use of non-tunneled catheters. Recently, ultrasound guidance is being used widely in developed countries for TCC insertions for urgent haemodialysis initiation. Aim: The aim of the present study was to look at whether ultrasound guided TCC is a useful bridge to Arteriovenous Fistula (AVF) in haemodialysis patients and also to look at the incidence of catheter insertion complications, infective and bleeding complications and have data on catheter longevity. Materials and Methods: The present study was a prospective observational study. 106 TCC insertion procedures were performed between July 2017 and December 2018 in Nephrology interventional suite at St Johns MedicalCollege and Hospital, Bengaluru, Karnataka, India, using ultrasound guidance for accessing Internal Jugular Vein (IJV) by Nephrologist. Fluoroscopy was used in none. The success rate, insertion complications, infections and other catheter outcomes like bleeding, catheter blocks and catheter longevity of TCC inserted using ultrasound guidance alone were studied. Further, the patients were followed-up for a minimum period of nine months. Data was recorded in the predesigned Epi info version 7.0 proforma and analysed by SPSS software version 24. Results: There was 100% success rate for uncomplicated insertions of right IJV. No increase in major/minor bleeding complications was noted. Of the 106 insertions, only a single patient had a catheter kink. Mean blood flow was 230.3 ml/min. Cather Related Blood Stream Infecton (CRBSI) rate was 1.65 per 1000 catheter days. On follow-up, 59 of 72 patients underwent AVF creation, five underwent renal transplant and another five were converted to Continuous Ambulatory Peritoneal Dialysis (CAPD) and three patients with Acute Kidney Injury (AKI) requiring prolonged dialysis had renal recovery. Conclusion: TCCs for haemodialysis initiation can be safely placed by using ultrasound guidance. It can be used for longer period and is a useful bridge to AV fistula. There is 100% success rate for right-sided jugular TCC insertions using ultrasound alone. There are very less infective and bleeding complications with TCC usage.

Economic evaluation of suture versus clip anastomosis in arteriovenous fistula creation

ObjectiveTechniques such as the use of nonpenetrating vascular clips for arteriovenous fistula (AVF) anastomotic creation have been developed in an effort to reduce fistula-related complications. However, the outcomes data for the use of clips have remained equivocal, and the cost evaluations to support their use have been largely theoretical. Therefore, the present study aimed to determine both the clinical and the cost outcomes of AVFs created with nonpenetrating vascular clips compared with the continuous suture technique during a 10-year period at a single institution. MethodsAll patients undergoing AVF creation in the upper extremity from 2009 through 2018 were retrospectively analyzed. The patient demographics and AVF outcomes were collected and compared stratified by the surgical technique used. A cost analysis was performed of a subgroup of patients from 2013 to 2018. ResultsDuring the 10-year study period, 916 AVFs were created (79% using the continuous suture technique and 21% using nonpenetrating vascular clips). Patient demographics and comorbid conditions did not differ between the two groups, and no differences were present in maturation, primary patency, assisted primary patency, or complication rates between the two groups at 1 year. The suture group had a shorter time to maturation (4.3 months vs 5.5 months; P < .01) and improved secondary patency compared with the clip group (77.13% vs 69.59%; P = .03) The cost analysis of the procedures revealed a significant difference in direct costs (suture, $1389.26 vs clip, $1716.51; P < .01) and contribution margin (suture, $1770.19 vs clip, $1128.36; P < .01) for the two groups. ConclusionsBoth suture and clip techniques in AVF creation demonstrated equivalent rates of maturation, primary patency, assisted primary patency, and complications at 1 year with higher expense associated with the use of clips. Thus, in an effort to reduce the economic burden of healthcare in the United States, the findings from the present study support the preferential use of the standard polypropylene suture technique when creating upper extremity AVFs.

Maturation Rates of Arteriovenous Fistulas Using Small Veins in the Era of Endovascular Interventions

Traditional practice suggests the abandonment of veins smaller than 3mm in diameter for arteriovenous fistula (AVF) creation because of a low rate of maturation. This study aims to show that with balloon-assisted maturation (BAM), undersized veins can be used to create functional AVFs with a high rate of success. All patients who underwent AVF creation between 2014 and 2018 at a tertiary academic medical center were retrospectively reviewed. The patients without preoperative vein mapping, those who failed to follow-up, and the patients who were not on dialysis were excluded. A fistula was considered to be mature if it was successfully cannulated for dialysis. A total of 596 patients were identified for analysis. The cohort was divided into the small-vein group (SVG, <2.5mm) and large-vein group (LVG, ≥2.5mm) based on preoperative vein size. Categorical variables were analyzed with the chi-squared test for their association with maturation status. Continuous variables were analyzed with the Wilcoxon rank sum test. A P-value less than 0.05 was considered significant. In the study cohort, 61.9% of the patients were male, with an average age of 62.8±13.7years, and an average preoperative vein size of 2.9±1.1mm. With similar demographic distribution, the participants in the SVG (n=216) had significantly smaller preoperative vein size of 1.9±0.4mm than the patients in the LVG (n=380), 3.5±0.8mm (P=0.001). There were significantly more radio-cephalic AVFs created in the SVG (77.8% versus 48.7%, P<0.0001). The overall maturation rate was 83.1% (n=495), 219 fistulas (36.7%) matured primarily and 276 (46.3%) required interventions. Ninety-one percent of the patients required only 1 or 2 BAMs to achieve maturation. The SVG achieved a maturation rate of 75.9% as compared with 87.1% in the LVG (P=0.002). A significantly higher number of patients in the SVG required BAM for maturation as compared with the LVG (67.7% versus 49.9%, P=0.0002); however, there was no difference in the average number of BAMs required for fistula maturation between the groups (1.5±0.8 for the SVG vs. 1.4±0.7 for the LVG). In multivariable logistic regression analysis, vein size ≥2.5mm (odds ratio (OR)=2.11, confidence interval (CI): 1.36-3.27, P=0.0009) and male sex (OR=2.30, CI: 1.49-3.57, P=0.0002) were independent predictors of maturation. Small veins can be used for AVF creation with lower but still favorable maturation rates using BAM interventions, especially in male patients. This practice can increase the creation of autogenous dialysis access and potentially reduce complications related to prosthetic dialysis access.

Functional outcomes of arteriovenous fistulas recruited with regional anesthesia

ObjectiveRegional anesthesia (RA)-induced vasodilation increases the proportion of patients with vein anatomy suitable for arteriovenous fistula (AVF) creation. The functional outcomes of AVFs created with veins initially small for size on preoperative duplex ultrasound mapping (≤2.4 mm) that are recruited under RA have not been clearly defined. We aimed to evaluate freedom from revision or thrombosis, time to first cannulation, and reintervention rates of AVFs created with veins recruited after induction of RA. MethodsA prospectively maintained quality improvement database from a single institution was queried for patients who had dialysis access created under RA. We compared AVFs created according to the original surgical plan (preoperative minimum vein diameter >2.5 mm) with AVFs recruited with RA (preoperative minimum vein diameter ≤2.4 mm). End points included freedom from revision or thrombosis, time to first cannulation, and reintervention rates. ResultsBetween May 2014 and April 2018, there were 208 dialysis access cases performed under RA. Excluding grafts, revisions, patients with previous ipsilateral AVFs, and those without preoperative ultrasound vein mapping, 135 patients were included in our analysis. Induction of RA with intraoperative duplex ultrasound allowed a change in surgical plan in 55 of 135 (42%) patients (recruited with RA), including 31 patients originally scheduled for an arteriovenous graft (mean preoperative distal upper arm cephalic vein diameter of 1.8 mm [standard deviation, 0.2 mm]) who were converted to an AVF (12 brachiobasilic, 11 brachiocephalic, and 8 radiocephalic). The remaining patients in the group of AVFs recruited with RA included 13 scheduled for brachiobasilic configurations who were converted to brachiocephalic or radiocephalic AVFs and 11 scheduled for brachiocephalic AVFs who were converted to radiocephalic AVFs. Comparing AVFs created according to the original surgical plan vs AVFs recruited with RA, there were no differences in reintervention rates (48% vs 49%; P = .90) or functional outcomes at 6 months (60% vs 65% used on hemodialysis [P = .58] and 7% vs 2% primary failure [P = .19]). ConclusionsIn this series, RA increased the proportion of patients who underwent AVF creation without compromising functional outcomes. Routine use of RA in access surgery could have significant implications in meeting national guidelines for autogenous access in the prevalent hemodialysis population.

Primary Failure of Autogenous Arteriovenous Fistula: Critical Analysis.

Introduction:Permanent vascular access is an essential intervention in patients with advanced chronic kidney disease (CKD) and its success depends on various non-modifiable and modifiable factors. Considering the element of unpredictability and failure, we attempted to analyze various factors responsible for primary arteriovenous fistula (AVF) failure in presumed high-risk groups.Materials and Methods:We conducted an observational study of newly created AVFs at a tertiary referral government hospital in Eastern India between January 2014 and June 2015. All adult CKD patients undergoing AVF creation were included. Primary AVF failure was assessed at 12 weeks and total follow-up was 24 weeks in presumed high-risk groups of females, patients aged ≥65 years and those with diabetes mellitus.Results:Female gender was at a higher risk of primary AVF failure if aged ≥65 years (P = 0.0026), second AVF creation (P = 0.03), loupe magnification not used (P = 0.03), arterial plaque (P = 0.028), absent immediate thrill, and with radiocephalic AVF (P = 0.02). Absent immediate thrill (<0.0001) and AVF size ≤5 mm (P = 0.002) were important independent risk factors for primary failure. Diabetes or elderly age did not have additional risk, except with uncontrolled hypertension and female gender.Conclusion:Female gender was at a higher risk of poor unassisted AVF patency if their age was ≥65 years, had second AVF creation, loupe magnification not used or if arterial plaque was present. An absence of thrill immediately or at 24 hours or an AVF diameter ≤5 mm were independent intraoperative factors for poor outcome. On the contrary, diabetics, elderly males and intimal thickness were essentially noncontributors for AVF failure, except in few subsets.

Patients referred for arteriovenous fistula construction: a retrospective outcome analysis.

With lower rates of sepsis and re-interventions, arteriovenous fistula (AVF) is the preferred vascular access modality. The aim of this study is to evaluate the outcomes of patients referred for AVF construction at a single center in Cork, Ireland. The current study is a single-center retrospective review of all patients who underwent AVF creation between 2015 and 2017. Additionally, the kidney disease clinical patient management system was used to provide statistics on AVF use in Ireland. 39.3% of hemodialysis patients in Ireland use an AVF for vascular access. Regional use ranged from 50 to 20% across Irish hemodialysis centers. At Cork University Hospital, 192 AVFs were created. The population was 69.3% male (n = 133), 30.7% female (n = 59) with a mean (±SEM) age of 58.8 ± 1.03years. 69.5% of females received a brachiocephalic AVF (BCAVF) while 13.6% had a radiocephalic AVF (RCAVF) constructed. Significance was seen when comparing gender and AVF type (p < 0.001). Fifty-four percent of the fistulae were brachiocephalic (n = 103), 33% were radiocephalic (n = 63), and 4% were brachiobasilic (n = 8). BCAVF patients (62.7 ± 1.2years) were significantly older than patients receiving a RCAVF (54.5 ± 1.9years, p < 0.001). A post-operative thrill or continuous flow on Doppler was present in 99% of patients (n = 190) with maturation and complication rates of 82.7% (n = 153) and 5.7% (n = 11) respectively. 69.9% of AVFs were needled for hemodialysis (n = 114). AVF outcomes at this center are consistent with reported statistics in the literature. Patient age, sex, and diabetic status may influence the use of proximal AVF. AVF creation rates in Ireland are below international reported recommendations.

Assessment of right heart functions in the patients with arteriovenous fistula for hemodialysis access: Right ventricular free wall strain and tricuspid regurgitation jet velocity as the predictors of right heart failure.

ObjectivesPrevious studies have mostly focused on the left-sided cardiovascular changes, but right-sided cardiac changes and predictive factors have not been examined in advance following arteriovenous fistula (AVF) creation. We aimed to identify new parameters which contribute to the prediction of right heart failure (RHF) after AVF creation.MethodsThe study cohort comprised 81 patients who underwent AVF creation between January 2014 and April 2019 in our center. The study cohort was divided into the patients with RHF ( n = 15, 18.5%) and without RHF ( n = 66, 72.5%) following AVF creation.ResultsMean age of cohort was 49.9 ± 14.7 years (range 23–66) and 39 (48.1%) were men. Approximately 74.07% (60 patients) were in New York Heart Association Class II and III profile preoperatively. Independent predictors for RHF following AVF were right ventricle longitudinal strain (RVLS) free wall &lt;-19% [odds ratio (OR) 2.31, 95% CI 1.02–3.22], and tricuspid regurgitation jet velocity (TRJV) &gt;2.5 m/s [odds ratio (OR) 5.68, 95% CI 1.21–4.38]. Receiver operating characteristic analysis was performed with a resulting area under the curve value of 0.86 (95% CI 0.55–0.89, p = 0.004) for RVLS free wall &lt;-14.2% and 0.81 for TRJV &gt;2.61 m/s (95% CI 0.55–0.89, p = 0.005) in predicting RHF following AVF.ConclusionsRVLS free wall &lt;-14.2% and TRJV &gt;2.61 m/s were independent predictors of RHF following AVF creation. The patients at risk for having RHF following AVF creation or who may benefit from AVF should be identified with predictive parameters and prospective clinical studies.