Autologous Arteriovenous Fistula Research Articles

#3008 Very low protein diet with ketoanalogues supplementation could start haemodialysis with AVF without additional CVCs insertion

Abstract Background and Aims Nutritional interventions and a low-protein diet (LPD) are a critical point in the management of chronic kidney disease (CKD). Several protein-restricted dietary regimens have been proposed in patients with end stage kidney disease: a typical LPD provides around 0.6–0.7 g·kg meanwhile a very low-protein diet (VLPD) provides around 0.3–0.4 g·kg and it is basically a vegetarian diet which has to be supplemented with essential amino acids (EAA) to satisfy the body nitrogen need and with nitrogen-free ketoanalogues (KA) to recirculate the endogenous urea, whose serum levels are elevated in patients with CKD. KA and EAA reduce the rate of progression of chronic kidney disease and improve the inflammatory state; they reduce the absorption of phosphates and can maintain a good state of nutrition even if associated with diets with very low protein content. On the contrary, an excessively restrictive and inadequate diet in terms of EAA or calorie intake induces a negative nitrogen balance, therefore cachexia. The recommended vascular access to start dialysis treatment is represented by the arteriovenous fistula (AVF). An early referral to the vascular surgeon for vascular access creation is pivotal for deciding on a patient-specific strategy for planning access. Guidelines advise referral at least 3–6 months before the expected start of HD, because time is needed for AVF maturation and possible repeat interventions when it is impaired. An early referral results in more autologous AVFs, which have a better long-term patency, whereas late referral, results in a greater risk of AVF non-maturation and failure and therefore the need for additional central venous catheters (CVCs) to initiate dialysis. Recent studies have shown that pre-dialysis patients who undergo a VLDP + KA require less emergency dialysis access and have better elasticity of the arterial wall, better maturation rates and duration of the AVF and sometimes a reduction in the uremic toxins responsible of endothelial dysfunction. The aim of the study was to evaluate if patients could start haemodialysis with fistula cannulation, without central venous catheter insertion. Method 10 patients, late referral end stage renal disease were enrolled in a prospective, single arm study starting very low protein diet supplemented with ketoanalogues after arteriovenous fistula creation; they were followed with periodically assessment of renal function, uremic toxin, and acid-base balance until they need to start haemodialysis. It was evaluated AVF maturation and needs to additional CVC insertion. Results Patients (3 females, 7 males) mean age was 71.2 years; before AVF creation, baseline mean value was: sCr: 6.46 mg/dl, sUrea: 150 mg/dl, phosphorus: 4.45 mg/dl, bicarbonates: 19.8 mmol/l, eGFR: 8,37 ml/min. After 3 months of VLPD supplemented with KA, eGFR and sCr was stable to 8.25 ml/min and 6.69 respectively, sUrea and phosphorus reduced to 115 mg/dl and 3.8 mg/dl, and bicarbonate increased to 22.4 mmol/l. All 10 patients achieved AVF maturation within 3 months, no one needed CVC insertion. Conclusion In this small group we see how late referral ESRD patients, undergone AVF surgery, after 3 months of VLPD supplemented with KA, had stability of renal function, with reduction of urea and phosphorus, improvement of acid-base balance and achievement of AVF maturation, without needing of CVC insertion. For these reasons VLPD + KA could be useful in delaying haemodialysis start in late referral ESRD patients who have created AVF, without emergency placement of a central venous catheter.

Regulation of vascular remodeling by immune microenvironment after the establishment of autologous arteriovenous fistula in ESRD patients.

Autogenous arteriovenous fistula (AVF) is the preferred dialysis access for receiving hemodialysis treatment in end-stage renal disease patients. After AVF is established, vascular remodeling occurs in order to adapt to hemodynamic changes. Uremia toxins, surgical injury, blood flow changes and other factors can induce inflammatory response, immune microenvironment changes, and play an important role in the maintenance of AVF vascular remodeling. This process involves the infiltration of pro-inflammatory and anti-inflammatory immune cells and the secretion of cytokines. Pro-inflammatory and anti-inflammatory immune cells include neutrophil (NEUT), dendritic cell (DC), T lymphocyte, macrophage (Mφ), etc. This article reviews the latest research progress and focuses on the role of immune microenvironment changes in vascular remodeling of AVF, in order to provide a new theoretical basis for the prevention and treatment of AVF failure.

Differential expression of serum TM, PAF, and CD62P in patients with autologous arteriovenous fistula and the correlation with vascular access function.

End-stage renal disease (ESRD) is the final stage of chronic kidney disease (CKD). We aimed to analyze the expression differences of serum thrombomodulin (TM), platelet-activating factor (PAF), and P-selectin (CD62P) in patients with autologous arteriovenous fistula (AVF) and the correlation with vascular access function. The case data were retrospectively analyzed. Moreover, 160 patients with AVF maintenance hemodialysis were selected as the AVF group, and 150 healthy participants were selected as the healthy control group. According to the function of vascular access, patients in the AVF group were divided into Group A (n = 50, after the first establishment of AVF), Group B (n = 64, normal vascular access function after hemodialysis treatment), and Group C (n = 46, vascular access failure). Pearson analysis was conducted to explore the correlation between serum TM, PAF, CD62P content, and vascular pathological examination indicators, to evaluate the value of TM, PAF, and CD62P levels in predicting vascular access failure in patients with AVF. The serum levels of TM, PAF, and CD62P were positively correlated with the expressions of CD68 and MCP-1, respectively (p < .001). Serum TM was positively correlated with the levels of PAF and CD62P (p < .001), and PAF was positively correlated with the levels of CD62P (p < .001), respectively. Serum levels of TM, PAF and CD62P were risk factors for vascular access failure in AVF patients (p < .05). The area under the curve of serum TM, PAF and CD62P levels in predicting vascular access failure in AVF patients was 0.879. The serum levels of TM, PAF, and CD62P in AVF patients were correlated with the vascular access function of AVF patients, which was very important for maintaining the stability of vascular access function, and had certain value in predicting vascular access failure/disorder in AVF patients, and could be popularized and applied.

Logistic regression analysis of risk factors for hematoma after autologous arteriovenous fistula in hemodialysis patients.

To determine the risk factors and nursing countermeasures for post-operative hematoma in hemodialysis patients with autogenous arteriovenous fistula by logistic regression analysis. A retrospective analysis of 240 chronic hemodialysis patients admitted to our hospital from January 2019 to October 2022 was performed. Physical and vascular examinations of the patients were performed by surgeons. Continuous care measures were implemented for all patients. The patient serum creatinine (Scr) and blood urea nitrogen (BUN) were measured on the day of inclusion and after the implementation of care measures. Self-management scales were used to analyze patients' self-management. Fatigue symptoms were assessed using the Fatigue Scale 14. The WHO Quality of Life Scale (WHOQOL-BREF score) was used to assess patients' quality of life. Self-Rating Depression Scale and Self-Rating Anxiety Scale (SAS) were used to assess negative affect. Treatment compliance was assessed according to 3 levels: complete compliance, compliance, and noncompliance. In all, 240 patients underwent 240 initial and 48 repeat procedures; 18 of the 240 patients experienced fistula failure, with an overall success rate of 92.5% (222/240). There were no significant differences in renal function, self-management, General Self-Efficacy Scale, fatigue symptom scores, and WHOQOL-BREF scores between the postoperative hematoma group and no-hematoma group before the continuous care. After continuous care, renal function, self-management, General Self-Efficacy Scale, fatigue symptom scores, and WHOQOL-BREF scores were better in the postoperative no-hematoma group than in the hematoma group, and the difference was statistically significant (P < .05). Logistic regression analysis of risk factors for postoperative hematoma showed that elevated Scr and BUN levels, decreased self-management and SAS scores and poor treatment compliance were independent risk factors for postoperative hematoma in hemodialysis patients with autologous arteriovenous fistulas (P < .05). Elevated Scr levels, elevated BUN levels, decreased self-management scores, decreased SAS scores, and poor treatment compliance were independent risk factors for postoperative hematoma in hemodialysis patients with autogenous arteriovenous fistulas. By providing continuous care to hemodialysis patients based on timing theory, the negative emotions can be alleviated and the self-efficacy, quality of life, and treatment compliance of the patients can be improved.

Efficacy and safety of implantable vascular support in the treatment of arteriovenous fistula: A single-arm meta-analyses.

VasQ (Laminate Medical Technologies, Israel) is an external support device for autologous arteriovenous fistula (AVF) designed to improve anastomotic blood flow and reduce neointimal hyperplasia. However, different studies have shown that the efficacy of the VasQ device in improving AVF is inconsistent. The purpose of this study was to conduct a meta-analysis to further evaluate the efficacy and safety of the VasQ device. Two reviewers independently searched studies published in PubMed, EMBASE, Cochrane, Web of Science, CNKI, and Wan Fang databases from inception to 2023. The Cochrane Systematic Evaluation Bias Risk Tool Version 1 was used to assess the risk of RCTS bias. The ROBINS-I tool was used to assess the risk of bias in non-randomized studies. A Single-arm meta-analysis was performed, and a random effects model was used for all analyses. We identified six trials involving 146 patients and conducted a meta-analysis. The results showed that after 6 months of VasQ device treatment, the primary patency rate of AVF was [76.4% (95%CI: 0.608-0.920), p < 0.01] while the secondary patency rate was [76.5% (95%CI: 0.572-0.958), p < 0.01]. The maturity rate of AVF 1 month after surgery was [88.5% (95%CI: 0.818-0.952), p = 0.46]. The incidence of anastomotic stenosis was [8.9% (95%CI: 0.015-0.163), p = 0.23], and the incidence of anastomotic venous thrombosis was [10% (95%CI: 0.035-0.179), p = 0.38]. Meta-analysis data of this study show that the VasQ device has a good effect in improving the patency rate of AVF and does not increase the occurrence of adverse events. However, due to the limitation of the number and quality of included studies, more high-quality studies are needed to confirm this in the future.

Lipectomy as an alternative for superficialization of autologous AVF in obese patients: experience of a referral center in Amazon.

The preferred vascular access for hemodialysis is a native arteriovenous fistula (AVF) because it offers the best results in the short and long terms, lower morbidity and mortality, and has additional advantages in relation to central venous catheters or arteriovenous grafts. However, obesity can present an additional challenge because of the barrier of subcutaneous cellular tissue covering the surface of the vein to be punctured. The authors review their experience with excision of subcutaneous tissue (lipectomy) overlying upper arm cephalic vein arteriovenous fistulas in obese patients. Consecutive vascular access patients undergoing lipectomy for cannulation with difficult access because of vein depth were reviewed. Cephalic vein depth was measured by ultrasound in all cases. Twenty-two patients were reviewed (15 men and 7 women), with a mean body mass index of 34.0 kg/m2 (range: 28-40 kg/m2). Mean age was 58.4 years. The mean preoperative vein depth of 7.9 mm (range: 7.0-10.0 mm) was reduced to 4.7 mm (range: 3.0-6.0 mm) (P 0.01). The mean follow-up period for patients was 13.2 months. Four patients were lost to follow-up and four died during the period due to causes unrelated to vascular access. Obesity should not be a limiting factor to creation of a native AVF, since lipectomy is a relatively simple option for superficialization, enabling functioning native and deep arteriovenous fistulas in obese patients.

Vascular Access Blood Purification Treatments in Chronic Renal Failure: Impact on Quality of Life

Objective: To observe the effects of blood purification treatment and assess the prognostic impact of different vascular pathways on patients with chronic renal failure (CRF). Methods: A retrospective analysis of clinical data was conducted on 68 CRF cases, categorizing them based on their choice of blood purification vascular access. Group A received an autologous arteriovenous fistula, Group B received an internal jugular vein tunneled polyester sleeve catheter, and Group C received a polytetrafluoroethylene graft vascular fistula. Clinically relevant observation indicators, complication rates, and quality of life scores among the three groups were compared. Results: No significant differences were found between the three groups regarding observed values of clinically relevant indicators and quality of life scores (P &gt; 0.05). When comparing thromboembolism rates Group A had the highest rate, followed by Group C and Group B; for infection rate comparison, Group C had the highest rate, followed by Group B and Group A (P &lt; 0.05). Conclusion: In comparison with the other two vascular access methods, although autologous arteriovenous fistula poses a higher risk of thromboembolism, it exhibits a lower infection rate. Therefore, it is recommended as the preferred vascular access form for blood purification in patients with CRF. If this approach is unavailable, careful consideration should be given. The use of an internal jugular vein with a tunneled polyester sleeve catheter is suggested to better ensure the effectiveness and safety of the patient’s treatment.

Multicenter Randomized Controlled Trial of APERTO-Paclitaxel Drug-Eluting Balloon Angioplasty Versus Standard Percutaneous Transluminal Angioplasty in Dysfunctional Hemodialysis Grafts and Native Fistulae.

to assess the safety and efficacy of APERTO-Paclitaxel-coated balloon angioplasty versus standard angioplasty for the treatment of dysfunctional hemodialysis shunts and native arteriovenous fistulae. consecutive patients with dysfunctional dialysis related to underlying efferent vein stenosis were included and randomized 1:1 to either APERTO-paclitaxel drug-coated balloon (study arm) or standard percutaneous transluminal angioplasty (control arm). Primary endpoint is time from treatment until dialysis access dysfunction according to standardized Kidney Disease Outcomes Quality Initiative (KDOQI)-guidelines and assessed by Kaplan-Meier survival curves and tested for significance with log-rank analysis. Secondary endpoints include device, technical, and clinical success of the index angioplasty procedure. The study included 103 patients (n=51 study-group) with a de novo (n=33) dysfunctional native arteriovenous fistula (n=79) in the forearm (n=60). The majority of included patients were male with a mean age of 69.8 years, presenting with a dysfunctioning autologous arteriovenous fistula in the forearm. Device-related complications did not occur in any of the included patients. Functional hemodialysis access without need for re-intervention at 1 year after index procedure was found in n=10 (19.6%) and n=5 (9.6%) of patients treated with, respectively, paclitaxel drug-coated balloon and percutaneous transluminal angioplasty (p=0.612). A nonsignificant benefit of paclitaxel drug-coated balloon (n=5; 25%) over percutaneous transluminal angioplasty (n=1; 11%) was found (p=0.953) in de novo lesions in autologous fistulas. APERTO-paclitaxel drug-coated balloon is a safe balloon catheter to manage dysfunctional hemodialysis access; however, longer period of adequate hemodialysis circuit functioning after endovascular index stenosis treatment, using APERTO-paclitaxel drug-coated balloon versus percutaneous transluminal angioplasty could not be demonstrated. APERTO-paclitaxel drug-coated balloon catheter is a safe device to manage dysfunctional hemodialysis access. Compared to conventional angioplasty balloon, the APERTO drug-coated balloon will not result in longer period of adequate hemodialysis circuit functioning. A non-significant benefit of APERTO drug-coated balloon was found in de novo lesions in autologous fistulas.

The effects of health education and exercise style changes on the maturation of autologous arteriovenous fistula in hemodialysis patients: A randomized controlled trial.

Upper limb exercise has long been considered to be the main means to promote autogenous arteriovenous fistula (AVF) maturation, but in practice exercise intensity and compliance are both typically lacking. Several randomized controlled trials (RCTs) have demonstrated the good effects of functional resistance or pressure exercise in patients with AVF. However, many patients' have difficulty complying with upper limb exercise programs without systematic health education. Therefore, we argue that resistance and pressure exercise supported by health education is actually the most beneficial for AVF patients. We randomly divided 114 patients into a control group and an experimental group of 57 patients each. In the control group, conventional care was used, and in the experimental group, online health education based on the IMB (Information-Motivation-Behavior skills) model and functional resistance and pressure upper limb exercises was implemented with the AVF side arm. The failure rate of AVF maturation, clinical maturation time, cephalic venous blood flow, vessel diameter, and vessel skin thickness were compared between the two groups. Fifty-five cases were included for each in the final study. The primary outcome of this study was the failure rate of AVF maturation. Secondary outcomes included clinical maturation time, cephalic vein flow, vessel diameter, and vessel thickness. The failure rate of AVF maturation in the experimental group was significantly lower than that in the control group, and the clinical maturation time in the experimental group was significantly shorter than that in the control group. For the remaining three indicators, there were between-group effects, time effects, and interaction effects in both groups. Comparison between groups showed that there was no statistical difference in the observed indicators of cephalic vein flow, vessel diameter, or vessel thickness between the two groups before the intervention but that there was a statistical difference at the end of the 4th, 8th, and 12th weeks of the intervention. A 2 × 2 comparison also showed that there was a statistical difference between the three indicators at each time point within the two groups. IMB model-based online health education combined with functional resistance and pressure exercises can improve AVF maturation status and accelerate AVF maturation within 12 weeks of surgery.

Analysis of high-risk factors for failure of autologous arteriovenous fistula in hemodialysis patients

To investigate the high risk factors of failure of autologous arteriovenous fistula (AVF) in hemodialysis patients. A retrospective study was conducted, patients with maintenance hemodialysis (MHD) undergoing AVF admitted to General Hospital of Western Theater Command from January 2021 to December 2022 were enrolled, including 107 patients with normal AVF and 168 patients with AVF dysfanction. According to the causes of AVF failure, the patients were divided into AVF stenosis group (n = 103) and AVF thrombosis group (n = 65). Age, gender, body mass index (BMI) and comorbidities (hypertension, diabetes, coronary heart disease) and other clinical data of all patients were collected. Hemoglobin, hematocrit, white blood cell count, neutrophil count, lymphocyte count, platelet count, C-reactive protein (CRP), high density lipoprotein, low density lipoprotein, neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) within 1 month of AVF use in normal dialysis patients and 1 week before AVF failure. Multivariate Logistic regression was used to analyze the independent risk factors of AVF dysfuction in MHD patients. The receiver operator characteristic curve (ROC curve) was drawn to evaluate the predictive value of risk factors on AVF dysfuction in MHD patients. (1) There were significant differences in age, BMI, hypertension, hemoglobin, hematocrit, PLR and CRP [age (years): 56.94±14.32, 58.83±14.05, 51.57±13.19; BMI (kg/m2): 22.83±3.10, 21.27±4.98, 23.35±2.72; hypertension: 93.20%, 64.62%, 86.92%; hemoglobin (g/L): 110.82±22.16, 88.70±24.00, 87.95±23.45; hematocrit: 0.350±0.069, 0.282±0.076, 0.275±0.071; PLR: 197.35±113.59, 192.55±138.25, 162.12±73.25; CRP (mg/L): 10.01±4.02, 8.18±5.42, 3.17±1.30, all P < 0.05], among AVF stenosis group, AVF thrombosis group and AVF normal group, there were statistically significant differences no statistically significant difference was found in other indexes among three groups. (2) Multivariate Logistic regression analysis showed that hypertension [odds ratio (OR) = 4.849, 95% confidence interval (95%CI) was 1.278-18.397, P = 0.020], elevated CRP levels (OR = 2.104, 95%CI was 1.533-2.888, P = 0.000) were associated with AVF stenosis. Elevated CRP levels (OR = 1.984, 95%CI was 1.442-2.730, P = 0.000) was an independent risk factor for AVF thrombosis. Analysis of ROC curve showed that the area under the curve (AUC) of AVF dysfunction predicted by CRP was 0.712, 95%CI was 0.637-0.786, P = 0.000; CRP cut-off value was 1.8 mg/L, the sensitivity was 67.0%, the specificity was 83.7%. Elevated CRP is an independent risk factor for AVF failure in hemodialysis patients, which can be used to predict the occurrence of AVF failure.

The RADAR technique in reconstruction of failed autologous arteriovenous fistulas due to juxta-anastomotic stenosis is equivalent to that with traditional surgery in maintenance hemodialysis patients.

Autologous arteriovenous fistula (AVF) is recommended as superior vascular access for hemodialysis but has a high rate of failure, and juxta-anastomotic stenosis (JAS) is one of the predominant causes of fistula failure. The aim of this study was to compare the primary patency in reconstruction of failed AVFs due to JAS between the radial artery deviation and reimplantation (RADAR) technique and traditional surgery (end-vein to side-artery neo-anastomosis) in maintenance hemodialysis (MHD) patients. A total of 1215 MHD patients with failed AVF were enrolled in this retrospective cohort study, and 614 patients with failed AVF received surgical intervention. Among these surgical interventions, 417 patients experienced AVF failure due to JAS. Finally, 25 patients who received the RADAR technique were enrolled. Controls of 50 patients received traditional surgery were randomly selected matched by age and sex. Clinical data such as age, sex, comorbidities, and blood biochemical indices were collected. Kaplan-Meier survival curves and Cox proportional hazards analyses were used to explore the difference between the RADAR group and the traditional group in reconstruction of failed AVFs. The RADAR group and the traditional group shared common baseline characteristics. The primary patencies of the reconstructed AVFs were 88.8%, 79.0%, 72.2%, 57.4%, and 38.3% at 12, 24, 36, 48, and 60 months among the 75 patients, respectively. Kaplan-Meier survival curve analysis demonstrated similar primary patencies in the two groups (log-rank test, p = 0.73). Compared with the traditional group, the RADAR group had no difference in predicting AVF failure after adjusting for potential confounders, with an HR of 0.92 (95% CI, 0.18-4.63). The primary patency of the RADAR technique and the traditional surgery in the reconstruction of failed AVFs due to JAS is almost equal in 5 years.

Autologous forearm arteriovenous loop vascular access, an option to be considered

Background: Autologous arteriovenous fistula is usually the vascular access of choice for hemodialysis in patients with chronic kidney disease. Autologous forearm loops with cephalic or basilic vein are an alternative in those cases with a suitable forearm vein but with an unsuitable radial artery; however they are rarely used and there is little reported evidence of their usefulness. Our objective is to report our results on the creation of autogenous forearm loops as vascular access for hemodialysis. Methods: We present a prospective cohort study of autogenous forearm loop arteriovenous fistula created between 2010 and 2022, in patients with stage 4–5 chronic kidney disease. Demographic data, surgical details, vein used, follow up to 24 months, maturation, utilization, primary, assisted, and secondary patency estimations with Kaplan-Meier curves, as well as complications during follow-up, were recorded. Results: During the study period, 22 autologous forearm loops were created, 14 of them with cephalic, and 8 with basilic vein. Most (59%) of the patients were men, 19 were already on dialysis and the rest started during follow-up. Sixteen patients had previous vascular accesses. One patient was lost during follow-up. Six-week maturation rate was 61.9% and utilization rate was 57.1%. 6, 12, and 24 months primary and secondary patencies were 75.4%, 59.2%, 41.5% and 85.0%, 69.5%, 56.9% respectively. In five patients an access-induced distal ischemia was diagnosed, four successfully treated and only one patient lost the access. No cases of infection or other major complications were reported. Conclusion: Autologous forearm loops have acceptable maturation (61.9%) and patency rates at follow-up (56.9% 2-years secondary patency). Although rarely used, they are a vascular access alternative that should be considered to preserve the proximal vasculature of the arm for future accesses.

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.

Long-term efficacy and risk factors of balloon-assisted maturation for radial-cephalic arteriovenous fistula with small-caliber veins.

Balloon angioplasty maturation (BAM) is a salvage method for autologous arteriovenous fistula (AVF) maturation failure. AVF creation using small-diameter veins is considered to have poor outcomes. Therefore, this study aimed to explore the long-term patency of small-diameter veins (≤3 mm) using BAM. BAM was performed if the fistula failed to mature and function adequately to provide prescribed dialysis. Out of 61 AVFs, 22 AVFs successfully matured without further intervention (AVF group) and 39 AVFs failed to mature. Except for 1 patient who required peritoneal dialysis, the remaining 38 patients received salvage BAM, and 36 of those successful matured (BAM group). Kaplan-Meier analysis revealed no significant differences between the AVF and BAM groups in terms of primary functional patency (p = 0.503) and assisted functional patency (p = 0.499). Compared with the AVF group, the BAM group had similar assisted primary functional patency (1-year: 94.7% vs. 93.1%; 3-year: 88.0% vs. 93.1%; 5-year: 79.2% vs. 88.3%). In addition, there were no significant difference between groups in the duration of primary functional patency and assisted primary functional patency (p > 0.05). Multivariate analyses showed that vein diameter and number of BAM procedures were independent predictors of primary functional patency in the AVF group and BAM group, respectively. Patient with 1 mm increase in vein size had 0.13-fold probability of having decreased duration of patency (HR = 0.13, 95% CI: 0.02-0.99, p = 0.049), while patients who received two times of BAM procedures were 2.885 as likely to have decreased duration of primary functional patency (HR = 2.885, 95% CI: 1.09-7.63, p = 0.033) than patients who received one BAM procedure. BAM is a relatively effective salvage management option with an acceptable long-term patency rate, even for small cephalic veins.

Retrospective Study of Autologous Arteriovenous Fistula Creation as Vascular Access for Hemodialysis

IntroductionAn autologous arteriovenous fistula (AVF) creation is a common vascular procedure forhemodialysis (HD) patients. This surgical procedure aim is to design a vascular conduct thatwithstands hemodialysis for a durable period. However, the functional outcome of this procedurevaries and depends on patients’ various predictors. .MethodsA retrospective observational study was carried out to evaluate the functional outcome of AVFcreation at the cardiothoracic vascular surgery unit of the surgery department of B.P KoiralaInstitute of Health Sciences from February 2019 to February 2020. The medical file of the patientswas studied, relevant data entered and analyzed in SPSS statistical software.ResultsThere were a total of 112 autologous AVF created during the study period. The mean age ofthe patients was 48.66±15.64 years. There were 75(67%) males and 37(33%) females. The mostcommon limb of fistula creation was left non-dominant upper limb 95(84.8%) and right upper limb17(15.2%). The most common type of AVF was radiocephalic fistula 66(58.9%) and brachiocephalicfistula 46(41.1%). There were 92(82.1%) mature fistula at eight weeks follow-up. These include54(48.2%) radiocephalic fistulas and 38(33.9%) brachiocephalic fistulas. There were 20(17.8%)delayed matured fistulas at 12 weeks (12 radiocephalic and 8 brachiocephalic AVF).ConclusionsThe creation of an autologous AVF for hemodialysis in the upper limb has fewer complications andthe maturation of the AVF depends on the vessel’s diameter. Radio-cephalic and BrachiocephalicAVF usually matures between six to eight weeks duration

Management of Thrombosed Dialysis Access Circuits.

Thrombotic occlusion of autologous arteriovenous fistulas or synthetic arteriovenous grafts is a serious adverse event in hemodialysis patients and declotting should be performed before next hemodialysis session, in order to avoid a central venous catheter. Various techniques exist to declot a thrombosed vascular access, including open surgical thrombectomy, catheter-directed thrombolysis and use of different types of percutaneous thrombo-aspiration catheters and mechanical thrombectomy devices. These devices can be categorized as devices with direct wall contact and hydrodynamic devices without direct wall contact. Technical and early clinical outcome results of percutaneous hemodialysis declotting are high and ranging between 70 and 100%; late clinical patency results are much lower related to restenosis or re-thrombosis; these patency results are higher for autologous arteriovenous fistulas compared to synthetic arteriovenous grafts and mainly depend on the combined efficacy of successful thrombectomy and durable treatment of the underlying stenoses, associated with the acute thrombosis.

Clinical efficacy of a modified no-touch technique in the establishment of autologous arteriovenous fistula

Objective: To explore the clinical efficacy of a modified no-touch technique (MNTT) in establishing autogenous arteriovenous fistulas (AVF) in hemodialysis patients. Methods: A total of 63 patients with AVF which was first established by MNTT in the Department of Nephrology, Suzhou Science and Technology Town Hospital from January 2021 to August 2022 were retrospectively included. The clinical data, ultrasound evaluation data of AVF, AVF maturity rate and AVF patency rate were collected. Subsequently, the AVF rate of patients in the MNTT group was compared with the patency rate of patients in the conventional operation group in the same hospital from January 2019 to December 2020. The Kaplan-Meier method was used to draw the survival curve, and the log-rank test was used to compare the difference in postoperative patency rate between the two groups. Results: There were 63 cases in the MNTT group, with 39 males and 24 females, and aged (60±17) years. Meanwhile, there were 40 cases in the conventional operation group, including 23 males and 17 females, and aged (60±13) years. In the MNTT group, the immediate patency rate was 100% (63/63) after surgery, and the AVF maturation rate at 2, 4 and 8 weeks postoperatively were 54.0% (34/63), 85.7% (54/63), and 90.5% (57/63), respectively. The primary patency rate was 90.0% (45/50), 85.0% (34/40), 82.9% (29/35), and 81.0% (17/21) at 3, 6, 9 months, and 1 year after the operation, respectively, and the assisted patency rates were all 100.0%. The one-year primary patency rate in the MNTT group was higher than that in the conventional surgery group (81.0% versus 63.5%, log-rank χ2=5.12, P=0.023). Ultrasound results showed that in the MNTT group, AVF veins were evenly dilated, the vascular wall gradually thickened, the brachial artery blood flow gradually increased, and spiral laminar flow occurred in the cephalic vein and radial artery. Conclusion: AVF established by MNTT features with fast maturity and a high patency rate, which is worthy of clinical promotion.

Outflow Rescue of Elbow-Blockade Forearm Arteriovenous Fistulas: Outcomes of Open Surgical Techniques

Venous scarring at the elbow is a common problem that can cause early and late forearm arteriovenous fistula (AVF) dysfunction in hemodialysis patients. However, any effort to prolong the long-term patency of distal vascular accesses could benefit the patient's survival, maximizing the use of restricted venous patrimony. This study aims to report a single-center experience in the recovery of distal autologous AVF with venous outflow obstruction at the elbow using different surgical techniques. Retrospective observational study of all patients treated at a single vascular access center from January 2011 to March 2022, with dysfunctional forearm AVFs presenting with outflow stenosis or occlusions at the elbow treated by open surgery, using 3 different surgical techniques. Demographics and clinically relevant data were collected. Evaluated endpoints included primary, assisted primary, and secondary patency rates at 1 and 2years. Twenty-three patients with elbow-blocked outflow forearm AVFs have been treated with a mean age of 64±15years. The majority (96%) had a radiocephalic fistula. The median time from vascular access creation to intervention was 34.5months (12-216months). A total of 24 procedures have been performed using 3 different surgical techniques for bypassing the obstructed venous outflow at the elbow. Technical success was achieved in 96% of the surgically treated patients. Primary and secondary patency rates at 1year were 67.4% and 89.4%, respectively, and 52.9% and 82.0% at 2years, with a median follow-up of 19months (6-92months). AVFs outflow stenosis or occlusions at the elbow not amenable to endovascular therapy could lead to vascular access abandonment. Our study demonstrates multiple surgical solutions to avoid this adverse outcome. Elbow venous outflow surgical reconstruction seems effective for distal vascular access preservation. Close surveillance is essential for timely endovascular treatment of newly developed stenosis at the venous drainage.

Surgical creation of lower extremity fistula and grafts.

Lower limb vascular access (LLVA) should be considered for patients in whom upper extremity access has been exhausted. The decisional process around vascular access (VA) site selection should incorporate a patient centered approach that aligns with End Stage Kidney Disease life-plan as recently described in proffered in 2019 Vascular Access Guidelines. The current surgical approaches to LLVA can be divided into two main groups: (A) autologous arteriovenous fistulas (AVFs); (B) synthetic arteriovenous grafts (AVGs). The autologous AVFs include both the femoral vein (FV) and great saphenous vein (GSV) transpositions, while prosthetic AVGs in the thigh position are appropriate for certain patient subtypes. Good durability has been described for autogenous FV transposition as well as AVGs with both demonstrating acceptable primary and secondary patency rates. Major complications such as steal syndrome, limb edema, and bleeding and minor complications such as wound-related infection, hematoma and delayed wound healing have been noted. LLVA is commonly reserved for the patient in whom the only alternative VA may be a tunneled catheter with its attendant morbidity. In this clinical circumstance, successful LLVA has the opportunity to be a life-saving surgical therapy when successfully performed. We describe a thoughtful approach that focuses on patient selection to optimize success and mitigate complications associated with LLVA.

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.