Arteriovenous Fistula Maturation Rates Research Articles

Far-Infrared Therapy Improves Arteriovenous Fistula Patency and Decreases Plasma Asymmetric Dimethylarginine in Patients with Advanced Diabetic Kidney Disease: A Prospective Randomized Controlled Trial.

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide synthase and plays a significant role in the pathogenesis of arteriovenous fistula (AVF) dysfunction. The aim of this study is to evaluate the effect of far-infrared (FIR) therapy on the maturation and patency of newly-created AVFs in patients with advanced diabetic kidney disease (DKD) as well as the concurrent change in plasma ADMA. The study enrolled 144 participants with advanced DKD where 101 patients were randomly allocated to the FIR therapy group (N = 50) and control group (N = 51). Patients receiving FIR therapy had a decreased AVF failure rate within 12 months (16% versus 35.3%; p = 0.027); decreased incremental change of ADMA concentration at the 3rd and 12th month; increased AVF blood flow at the 1st, 3rd, and 12th month; increased 3-month physiologic maturation rate (88% versus 68.6%; p = 0.034); increased 1-year unassisted AVF patency rate (84% versus 64.7%; p = 0.017); and increased clinical AVF maturation rate within 12 months (84% versus 62.7%; p = 0.029) compared to the control group. The study demonstrates that FIR therapy can reduce the incremental changes in plasma ADMA concentration, which may be associated with the improvement of AVF prognosis in patients with advanced DKD.

Vascular Factors Affecting Outcomes of Snuffbox AV Fistula with Side-to-Side Anastomosis: A Single Institutional Observational Study

Background: Angioaccess is considered the "Tendon of Achilles" for hemodialysis. Arteriovenous fistula (AVF) is the commonly entailed vascular access for hemodialysis. Objectives: The present study evaluates the outcomes of anatomical snuffbox AVF by preoperative and postoperative color Doppler scans. It also determines the anatomical snuffbox AVF maturation rate concerning preoperative radial artery diameter (RAD), cephalic vein diameter (CVD), cephalic vein distensibility, and peak systolic velocity (PSV). Methods: This study was conducted from April 2020 to January 2021 on end-stage renal diseases (ESRD) patients undergoing an operation for anatomical snuffbox AVF creation at our center after taking permission from the institutional ethics committee and written informed consent from patients. Results: Thirty-five ESRD patients underwent snuffbox arteriovenous fistula (SBAVF) creation, including 68% males and 32% females. Diabetes mellitus was noted in 40% and hypertension in 80%. Successful AVF maturation was noted in 92% (69.57% of males and 30.43% of females). The mean RAD assessed on color Doppler ultrasonography (CDUS) preoperatively was 1.79 mm, while the peak velocity of the radial artery at the snuffbox was 23.80 cm/s. Conclusions: We recommend applying the side-to-side configuration as its anastomosis angle is less owing to the lesser kink on the anastomotic site. A longer segment of anastomosis is achieved, and better fluid dynamics and WSS profiles are seen in this configuration with good outcomes.

Achieving high maturation and cannulation rates of radial-cephalic arteriovenous fistulas with VasQ™ device.

Hemodialysis is the predominant treatment modality for chronic kidney disease, with arteriovenous fistula (AVF) being considered to be the preferred type of long-term vascular access. Implantation of the external anastomotic VasQ™ support device during AVF creation has been suggested to improve the functional outcomes of AVFs. In the current study, we report the clinical outcomes when using the device with radial-cephalic AVF (RCAVF) creation in a large cohort over 3years. One hundred fifty RCAVFs were created between June 2018 and August 2021 with implantation of VasQ™. Time to maturation, cannulation characteristics, and assisted (AP) and secondary patency (SP) rates were analyzed. In this predominantly male (68%), median 64 years old cohort, 150 VasQ™ devices were implanted. Physiological maturation was achieved in 142/150 (95%) and was unassisted in 133/150 (89%). Of those, 129 matured within 1month and four additional AVFs within 165 days. Eight AVFs achieved maturation following percutaneous transluminal angioplasty, and one required surgical patch angioplasty. The median time from creation to first successful cannulation in dialysis patients was 41 days. AP at 6, 12, 18, 24, and 30 months was 89%, 81%, 78%, 73%, and 73%, and SP was 94%, 87%, 86%, 84%, and 84%, respectively. Consistent use of the VasQ™ device in RCAVF creation demonstrates excellent AVF maturation and patency rates with very low frequency of assisted maturation and interventions for maintenance. The VasQ™ device appears a suitable aid in increasing the creation of functional RCAVFs.

Arteriovenous fistula formation with adjuvant endovascular maturation

BackgroundThe clinical utility of the native arteriovenous fistula (AVF) has been limited by the prolonged time required for maturation, the low overall maturation rate, and subsequent abandonment. Endovascular intervention has been increasingly accepted as the first-line therapy for AVF stenosis. The objective of the present study was to evaluate the AVF formation outcomes when early endovascular intervention was selectively performed to bring about timely AVF maturation. MethodsWe performed a retrospective study (February 2014 to February 2020) of 82 AVF consecutive patients (mean age, 62.5 ± 13.5 years; range, 17-83; 58 men [70.7%]) with end-stage renal failure who had undergone vascular access construction at a single institution. The 4-year AVF patency, vascular diameters, hemodialysis parameters, reintervention rate, and mortality were analyzed. ResultsRadiocephalic AVF was the most common fistula constructed (71 patients; 88.6%). The evaluation at a mean of 46.2 ± 56.0 days (range, 5-343 days) after AVF formation revealed 33 immature AVFs (40.2%). Subsequently, 19 patients had undergone endovascular procedures, including angioplasty and/or stenting of the juxta-anastomosis, cannulation zones, and/or outflow segments to bring about timely maturation of the AVF. Hence, 93.9% of the AVFs had reached functional patency (maturation) by 6 months after formation, with a mean time to maturation of 67.8 ± 65.9 days (range, 5-320 days). After reaching maturation, the primary access functional patency was 82% ± 4.3% at 6 months, 58% ± 5.5% at 12 months, and 34% ± 6.8% at 48 months. The primary assisted access functional patency was 95% ± 2.4% at 6 months, 90% ± 3.3% at 12 months, and 83% ± 4.7% at 48 months. A total of 121 endovascular interventions were performed to maintain patency, equating to an endovascular reintervention rate of 0.37 procedure/patient year. The mean arterial, venous, and brachial flow rates did not change significantly after maturation with a mean AVF (primary assisted functional patency) survival time of 5.9 ± 0.26 years (range, 5.33-6.36 years) from maturation. Only 12 thromboses had occurred after the first follow-up review after AVF formation. These were all salvaged using endovascular techniques, leading to 100% total secondary functional patency at 4 years. The 5-year estimated all-cause mortality was 45.6% ± 12.7%. ConclusionsThe AVF maturation rate and interval to maturation were improved when early endovascular intervention was selectively performed after AVF formation. This allowed for near universal maturation. In addition, once matured, the use of ongoing endovascular reinterventions allowed for a low reintervention rate and long-term patency, providing reliable long-term renal vascular access.

Transposition of brachiobasilic arteriovenous fistulas: One-stage or two-stage technique and factors affecting the early maturation.

The brachiobasilic transposition (BBT) arteriovenous fistula (AVF) is a valuable option especially for dialysis patients with previously failed vascular access. We aim to report factors affecting the maturation of BBT-AVF created with either one-stage or two-stage technique. BBT-AVF procedures between January 2015 and May 2019 by a dedicated vascular access team were investigated retrospectively. A total of 122 patients (63 males, 59 females), with 6 to 12 weeks of follow-up after the BBT-AVF procedure were included in the study. Patients of one-stage and two-stage techniques were compared for maturation rates. Patients with successful and failed maturation were compared for baseline characteristics and anatomic factors. Of 122 BBT-AVF procedures, 54 were created with the one-stage and 68 were created with the two-stage technique. The mean age of the patients was 58.2 ± 13.8, the mean brachial artery and basilic vein diameters were 3.91 ± 1.02 mm, and 3.39 ± 1.16 mm. Of 122 included patients, 88 (72.1%) had mature AVFs at follow-up. The AVF maturation rates were similar between the one- and two-stage groups (70.4% vs 73.5%; P=.699). Lower age (62.8 ± 12.5 vs 56.5 ± 13.9; P=.023) and greater brachial artery diameter (3.09 ± 0.84 mm vs 4.23 ± 1.76 mm; P < .048) were the only factors affecting the AVF maturation in univariate analysis. Gender, extremity side, diabetes mellitus, hypertension, and targeted vein diameter were not found to affect the AVF maturation (P=.301, P=.084, P=.134, P=.858, P=.127). Target artery diameter (P=.049) was the only significant factor affecting BBT-AVF maturation in multivariate analysis. One-stage and two-stage BBT-AVFs are similar in terms of maturation rates. Targeted artery diameter was the only factor important in BBT-AVF maturation in our study group. The two-stage technique can be preferred considering smaller incision size and lower complication rate in patients with suitable anatomy.

Early Predictors of Arteriovenous Fistula Maturation: A Novel Perspective on an Enduring Problem.

Preoperative ultrasound mapping is routinely used to select vessels meeting minimal threshold diameters for surgical arteriovenous fistula (AVF) creation but fails to improve AVF maturation rates. This suggests a need to reassess the preoperative ultrasound criteria used to optimize AVF maturation. We retrospectively identified 300 catheter-dependent patients on hemodialysis with a new AVF created between 2010 and 2016. We then evaluated the associations of preoperative vascular measurements and hemodynamic factors with unassisted AVF maturation (successful use for dialysis without prior intervention) and overall maturation (successful use with or without prior intervention). Multivariable logistic regression was used to identify preoperative factors associated with unassisted and overall AVF maturation. Unassisted AVF maturation associated with preoperative arterial diameter (adjusted odds ratio [aOR], 1.50 per 1-mm increase; 95% confidence interval [95% CI], 1.23 to 1.83), preoperative systolic BP (aOR, 1.16 per 10-mm Hg increase; 95% CI, 1.05 to 1.28), and left ventricular ejection fraction (aOR, 1.07 per 5% increase; 95% CI, 1.01 to 1.13). Overall AVF maturation associated with preoperative arterial diameter (aOR, 1.36 per 1-mm increase; 95% CI, 1.10 to 1.66) and preoperative systolic BP (aOR, 1.17; 95% CI, 1.06 to 1.30). Using receiver operating curves, the combination of preoperative arterial diameter, systolic BP, and left ventricular ejection fraction was fairly predictive of unassisted maturation (area under the curve, 0.69). Patient age, sex, race, diabetes, vascular disease, obesity, and AVF location were not associated with maturation. Preoperative arterial diameter may be an under-recognized predictor of AVF maturation. Further study evaluating the effect of preoperative arterial diameter and other hemodynamic factors on AVF maturation is needed.

Preoperative noninvasive artery flow volume and maturation of arteriovenous fistulae: A single surgeon's experience from 403 cases.

Preoperative Doppler ultrasound evaluation of arteriovenous fistula inflow artery includes measurements of arterial diameter and flow volume. The purpose of this study was to evaluate the significance of flow volume to arteriovenous fistula maturation rate. Review of consecutive patients who underwent arteriovenous fistula creation by a single surgeon. Cases with available preoperative arterial diameter and flow volume were analyzed. Primary end point was arteriovenous fistula failure to mature. Information collected included demographics, Doppler ultrasound reports, level of inflow artery, operative reports, and outcomes to the time of arteriovenous fistula maturation or failure. Risk factors were identified by logistic regression analysis. Outcomes were compared by odds ratio. Four hundred and three cases were identified. Arterial diameter and flow volume were both independent significant risk factors affecting arteriovenous fistula maturation rate (p = 0.001). Arterial diameter of <2.5 mm and flow volume of <20 mL/min predicted failure to mature with 95% specificity. Further comparison of cases with optimal arterial diameter but flow volume of <20 mL/min showed increased failure to mature rate compared to the combination of optimal arterial diameter with optimal flow volume (p = 0.01). Preoperative arterial diameter and flow volume values were both significant independent variables affecting arteriovenous fistula maturation rate. However, flow volume of <20 mL/min remained a significant risk factor to failure-to-mature rate, despite optimal arterial diameter.

Surgeon Characteristics and Dialysis Vascular Access Outcomes in the United States: A Retrospective Cohort Study

An arteriovenous fistula (AVF) is the preferred access for most patients receiving maintenance hemodialysis, but maturation failure remains a challenge. Surgeon characteristics have been proposed as contributors to AVF success. We examined variation in AVF placement and AVF outcomes by surgeon and surgeon characteristics. Retrospective cohort study. National Medicare claims and web-based data submitted by dialysis facilities on maintenance hemodialysis patients from 2009 through2015. Patient characteristics, including demographics and comorbid conditions; surgeon characteristics, including specialty, prior volume of AVF placements, and years since medical school graduation. Percent of access placements that were an AVF from 2009 to 2015 (designated AVF placement), and percent of AVFs with successful use within 6 months of placement (maturation) from 2013 to2014. Multilevel logistic regression models examining the association of surgeon characteristics with the outcomes, adjusted for patient characteristics and dialysis facilities as random effects. Among 4,959 surgeons placing 467,827 accesses, median AVF placement was 71% (IQR, 59%-84%). More recent year of medical school graduation and general surgery specialty (vs vascular, cardiothoracic, or transplantation surgery) were associated with higher odds of AVF placement. Among 2,770 surgeons placing 49,826 AVFs, the median AVF maturation rate was 59% (IQR, 44%-71%). More recent year of medical school graduation, but not surgical specialty, was associated with higher odds of AVF maturation. Greater prior volume of AVF placement was associated with higher odds of AVF maturation: OR of 1.46 (95% CI, 1.37-1.57) for highest (>84 AVF placements in 2years) versus lowest (<14) volume quintile. The study relied on administrative data, limiting capture of some factors affecting access outcomes. There is substantial surgeon-level variation in AVF placements and AVF maturation. Surgeons' prior volume of AVF placements is strongly associated with AVF maturation.

Arteriovenous fistula maturation rate is not affected by ipsilateral tunneled dialysis catheter

ObjectiveThe effect that ipsilateral tunneled dialysis catheters (TDC) have on arteriovenous fistula (AVF) maturation is unclear. We sought to define this association by comparing AVF maturation rates in patients with contralateral TDC with those with ipsilateral TDC. MethodsA review of a prospectively maintained database including all AVF creation procedures between 2009 and 2016 was performed. All patients with a TDC in place at the time of AVF creation were included in this study. Clinical and functional maturation rates were compared in patients with contralateral vs ipsilateral dialysis catheters. Categorical variables were analyzed by a two-tailed Fisher's exact test. A P value of less than .05 was considered statistically significant. ResultsThere were 187 patients who underwent fistula creation with a TDC in place during the study period. Of those, 137 patients had a contralateral TDC and 50 had an ipsilateral TDC. A greater proportion of contralateral patients were first-time dialysis access patients at the time of index AVF creation (67% vs 48%; P = .03). There was no difference in clinical (contralateral 73% vs ipsilateral 78%; P = .57) and functional (contralateral 64% vs ipsilateral 74%) maturation rates between the two groups. The rate of TDC removal after AVF maturation was also not different (contralateral 64% vs ipsilateral 72%; P = .30). There was also no statistical difference in the rates of thrombosis at less than 30 days, outflow stenosis, central stenosis, and steal syndrome. ConclusionsThere was no association between TDC sidedness and AVF maturation or early failure in our cohort. Planning for AVF creation should not be influenced by attempts to avoid an ipsilateral TDC.

Mineral Metabolism Disturbances and Arteriovenous Fistula Maturation

The arteriovenous fistula (AVF) is central to haemodialysis treatment, but up to half of surgically created AVF fail to mature. Chronic kidney disease often leads to mineral metabolism disturbances that may interfere with AVF maturation through adverse vascular effects. This study tested associations between mineral metabolism markers and vein histology at AVF creation and unassisted and overall clinical AVF maturation. Concentrations of fibroblast growth factor 23, parathyroid hormone, calcium, phosphate, and vitamin D metabolites: 1,25(OH)2D, 24,25(OH)2D, 25(OH)D, and bioavailable 25(OH)D were measured in pre-operative serum samples from 562 of 602 participants in the Haemodialysis Fistula Maturation Study, a multicentre, prospective cohort study of patients undergoing surgical creation of an autologous upper extremity AVF. Unassisted and overall AVF maturation were ascertained for 540 and 527 participants, respectively, within nine months of surgery or four weeks of dialysis initiation. Study personnel obtained vein segments adjacent to the portion of the vein used for anastomosis, which were processed, embedded, and stained for measurement of neointimal hyperplasia, calcification, and collagen deposition in the medial wall. Participants in this substudy were 71% male, 43% black, and had a mean age of 55 years. Failure to achieve AVF maturation without assistance occurred in 288 (53%) participants for whom this outcome was determined. In demographic and further adjusted models, mineral metabolism markers were not significantly associated with vein histology characteristics, unassisted AVF maturation failure, or overall maturation failure, other than a biologically unexplained association of higher 24,25(OH)2D with overall failure. This exception aside, associations were non-significant for continuous and categorical analyses and relevant subgroups. Serum concentrations of measured mineral metabolites were not substantially associated with major histological characteristics of veins in patients undergoing AVF creation surgery, or with AVF maturation failure, suggesting that efforts to improve AVF maturation rates should increase attention to other processes such as vein mechanics, anatomy, and cellular metabolism among end stage renal disease patients.

Effect of local papaverine on arteriovenous fistula maturation in patients with end-stage renal disease.

Background:Arteriovenous fistula (AVF) maturation is one of the main concerns in patients with end-stage renal disease (ESRD) and finding a strategy for increasing success rate and accelerating fistula maturation is valuable. The aim of this study was to evaluate the effects of papaverine injection on AVF maturation and success rate.Method:This study was a randomized clinical trial that involved 110 patients with ESRD that were referred for AVF construction. Patients were allocated in papaverine group and control group with block randomization according to age and sex. In the case group, papaverine (0.1 or 0.2 cc) was injected locally within the subadventitia of artery and vein after proximal and distal control during AVF construction and in the control group, AVF construction was done routinely without papaverine injection.Results:Maturation time in case and control groups was 37.94 ± 11.49 and 44.23 ± 9.57 days, respectively (p=0.004). Hematoma was not seen in the case group but occurred in one patient in the control group. One patient of the case group developed venous hypertension. Four functional fistulas, 1 (1.8%) in the case group and 3 (5.5%) in the control group, failed to mature (p=0.618). Maturation rate did not differ between the two groups statistically (p=0.101).Conclusion:Local papaverine injection increased vessel diameter and blood flow, increasing shearing stress in both arterial and venous segment of recently created AVF. In this way, papaverine probably can decrease AVF maturation time without an increase in complications.

A new method to determine anastomosis angle configuration for arteriovenous fistula maturation.

Background: The kidneys of patients with chronic kidney disease (CKD) do not function well enough and those in end-stage renal disease (ESRD) of CKD need hemodialysis (HD) as a common renal replacement therapy (RRT) procedure. HD requires a vascular access (VA), and arteriovenous fistula (AVF) is the common VA choice in the world due to its very few complications. Despite the widespread use of AVFs, some risk factors maximize AVF failure, which is accompanied by complications of the patient such as repeating VA surgeries and hospitalization. Therefore, finding effective factors in the success of surgery is highly important and, thus, this study aimed at measuring the effect of anastomosis angle on the success of AVF surgery. Methods: This study evaluated the effect of conducted angle in an AVF anastomosis on AVF maturation. The images of 48 created AVFs for CKD patients was provided over a one-year period (from May 2016 to April 2017). Cross-tab analysis was used, and significance level was considered meaningful at p-value≤0.001. A centralized database was designed to integrate data. A method for image processing was developed and geometrical characteristics of the vessels (such as anastomosis angle) and also the diameter of artery and vein were measured via AutoCAD 2017 software and exported to the database along with other data. Results: The rate of the AVF failure in the studied patients was 8.96%. The anastomosis angle ≤ 30° is preferable from the AVF status point of view because most AVF maturation (or least AVF failure) rates are detected at this range. Conclusion: This study was performed based on a new approach without the need to measure hemodynamic parameters. Moreover, it signified the important role of anastomosis angle in the function of AVF, showing that the anastomosis angle ≤ 30° is a preferable intraoperative recommendation for AVF surgery.

Correlation between preoperative vein and artery diameters and arteriovenous fistula outcome in patients with end-stage renal disease.

Background and aimsArteriovenous fistula (AVF) maturation failure rates remain high in patients with end-stage renal disease (ESRD). Although preoperative morphological and functional assessment of blood vessels by duplex ultrasonography (DUS) has been shown to improve AVF maturation, there is no consensus regarding the optimal vein (VD) and artery (AD) diameters to be universally used for AVF creation. To improve patient selection, set out to investigate if there is a correlation between preoperative VD/AD and clinical covariates, and postoperative AVF outcome.MethodsThis was a prospective cohort study conducted during January–August 2014. ESRD patients referred to “Niculae Stăncioiu” Heart Institute Cluj-Napoca, who had a VD ≥1.9 mm and AD ≥1.5 mm, as measured by DUS, and underwent AVF creation were enrolled. We assessed whether preoperative VD/AD and clinical covariates were associated with AVF maturation rate and primary patency at 2 years after AVF creation.ResultsOf 115 patients referred for AVF creation, 93 were included in the study. Mean (± standard deviation) VD was 3.3 ± 1.1 mm and VDs were distributed in quartile Q1 <2.55 mm, Q2: 2.56–3.10 mm, Q3: 3.11–3.70 mm and Q4: >3.71 mm. Mean AD was 3.3 ± 1.4 mm and ADs were distributed in Q1 <2.55 mm, Q2: 2.56–3.10 mm, Q3: 3.11–3.70 mm, and Q4, >3.71 mm. AVF maturation rate increased proportionally with VD from Q1 (62%) to Q2 (70%), Q3 (82%) to Q4 (96%) (p=0.03). Based on AD, a higher AVF maturation rate was observed in Q3 (86%), Q4 (83%) vs Q1 (71%) and Q2 (67%). Long-term primary patency of AVFs seemed not to be influenced by VD and AD. In older patients and those with peripheral arterial disease, AVF maturation failure tended to be higher.ConclusionsOur findings suggest that a preoperative VD ≥1.9 mm and AD ≥1.5 mm have a successful maturation rate of AVF greater than 60% in ESRD patients. The maturation rate of surgical AVF increases proportionally with the size of VD used for AVF creation.

VESS12. Arteriovenous Fistula Maturation Rate Is Not Affected by Ipsilateral Tunneled Dialysis Catheter

VESS12. Arteriovenous Fistula Maturation Rate Is Not Affected by Ipsilateral Tunneled Dialysis Catheter

Outcomes of arteriovenous fistula creation, effect of preoperative vein mapping and predictors of fistula success in incident haemodialysis patients: A single-centre experience.

Vascular access in haemodialysis is critical for effective therapy. We aim to evaluate the outcomes of arteriovenous fistula (AVF) creation in incident haemodialysis patients, impact of preoperative vein mapping and predictors of successful AVF maturation in our centre. Data of End-stage Renal Disease (ESRD) patients initiated on haemodialysis from January 2010 to December 2012 in our centre were retrospectively obtained from electronic medical records and clinical notes. Demographic characteristics, medical comorbidities, perioperative details were collected, and patients were followed up until 1 January 2014. A total of 708 patients (median age 64, IQR 55-72) were included with mean duration of follow up of 2.3 ± 1.2 years, with access of AVF and arteriovenous graft (AVG) in 694 (98%) and 14 (2%) patients respectively. Eight patients were lost to follow-up. Successful AVF maturation was achieved in 542 patients (78%), with 1-year cumulative patency rate of 74%. Multivariate analysis revealed male gender, upper arm AVF and good postoperative thrill and pulse as predictors of successful AVF maturation. Preoperative vein mapping was performed in 42.5% (295/694) of patients, with mean vein diameter of 2.44 ± 0.82 mm. Maturation rates with and without vein mapping were 72.2% and 82.4%, respectively, (P = 0.001). In patients with vein diameters of <2 mm and ≥2 mm, there was no statistically significant difference in maturation rates (71.3% vs. 72.6%; P = 0.887) and median maturation time (66 vs. 78 days; P = 0.73). Arteriovenous fistula can be successfully created in most incident haemodialysis patients. Routine vein mapping is not necessary if veins are suitable on physical examination alone, and vein sizes of <2 mm on ultrasound is not associated with lower AVF maturation rate.

Very low protein diets supplemented with keto-analogues in ESRD predialysis patients and its effect on vascular stiffness and AVF Maturation.

BackgroundNative arteriovenous fistula (AVF) is the most appropriate type of vascular access for chronic dialysis. Its patency rates depend on vascular wall characteristics. Ketoacid analogues of essential amino acids (KA/EAA) are prescribed in end-stage renal disease (ESRD) pre-dialysis patients to lower toxic metabolic products generation and improve nutritional status. We hypothesized that very-low protein diet (VLPD) supplemented with KA/EAA may influence arterial wall stiffness and affect AVF maturation rates and duration in pre-dialysis ESRD patients.MethodsIn a prospective, cohort, 3 years study we enrolled 67 consecutive non-diabetic early referral ESRD patients that underwent AVF creation in our hospital. Patients were divided in two groups based on their regimen 12 months prior to surgery: a VLPD supplemented with KA/EAA study group versus a low protein diet non-KA/EAA-supplemented control group. For each patient we performed serum analysis for the parameters of bone mineral disease, inflammation and nutritional status, one pulse wave velocity (PWV) measurement and one Doppler ultrasound (US) determination prior the surgery, followed by consequent Doppler US assessments at 4, 6, 8 and 12 weeks after it. Rates and duration of mature AVF achievement were noted. We used logistic regression to analyze the association between AVF maturation and KA/EAA administration, by comparing rates and durations between groups, unadjusted and adjusted for systolic blood pressure, C-reactive protein, PWV, phosphorus values. All parameters in the logistic model were transformed in binary variables. A p-value < α = 0.05 was considered significant; data were processed using SPSS 16 software and Excel.ResultsIn the study group (n = 28, aged 57 ± 12.35, 13 females) we registered better serum phosphate (p = 0.022) and C-reactive protein control (p = 0.021), lower PWV (p = 0.007) and a higher percent of AVF creation success (33.3 % versus 17.8 %, p < 0.05). AVF maturation duration was lower in study group (5.91 versus 7.15 weeks, p < 0.001).ConclusionsVLPD supplemented with KA/EAA appear to improve the native AVF primary outcome, decreasing the initial vascular stiffness, possible by preserving vascular wall quality in CKD patients through a better serum phosphate levels control and the limitation of inflammatory response.

Dialysis Access Surgery: Does Anesthesia Type Affect Maturation and Complication Rates?

Creation of an arteriovenous fistula (AVF) is the preferred method of establishing long-term dialysis access. There are multiple anesthetic techniques used for patients undergoing this surgery, including general endotracheal intubation (GET), laryngeal mask airway (LMA), regional anesthesia with nerve blocks, and monitored anesthesia care (MAC) with local infiltration (local/MAC). It is unclear what effect the method of anesthesia has on AVF creation success rate. Our objective was determine if anesthesia type affects success rates of AVF creation defined by complication and maturation rates. A retrospective review was performed in a single-institution, single-surgeon study of 253 patients who underwent AVF creation between January 2003 and December 2010. Patients were cross-analyzed between three anesthesia types (GET, LMA, and MAC) and AVF creation surgeries (radiocephalic, brachiocephalic, and basilic vein transposition AVF creations). No regional anesthesia was performed. Demographic data, including comorbidities and risk factors, were stratified among all categories. Analysis of variance, χ2 testing, and Fisher exact P testing was performed across all anesthesia types and specific operations and measured according to success of AVF maturation and complication rates (including death within 30 days, myocardial infarction within 30 days, respiratory insufficiency, venous hypertension, wound infections, neuropathy, and vascular steal syndrome). There were no significant differences in maturation rate in terms of the three anesthesia types (general, LMA, and local/MAC) for radiocephalic (P = .191), brachiocephalic (P = .191), and basilic vein transposition AVF creation (P = .305). In addition, there were no differences in complication rates between the surgeries and the three types of anesthesia (P = .557). Our study shows that despite anesthesia type, outcomes in terms of maturation and complication rate are not statistically different in AVF creation surgeries. The use of monitored anesthesia care with local anesthesia may improve operative efficiency and therefore may be the preferred method of anesthesia. Future studies can include cost analysis and implications for cost saving measures.

Effect of clinical examination and anatomical location on native arteriovenous fistula maturation rate in high risk patients

Introduction: Maximal use of native arteriovenous fistulas (AVFs) for patients on hemodialysis therapy remains a clinical challenge. Primary failure rates remain high with risk factors such as female gender, diabetes mellitus, lower arm AVF and higher age. We wondered if a strategy of careful clinical examination prior to AVF creation and a preference towards an upper arm AVF in case of doubt about the quality of the vein in patients with any of the above mentioned risk factors, would lead to better maturation rates.Methods: The records of all patients who received an AVF between January 2005 and December 2009 at our University Hospitals Leuven were studied retrospectively. Demographic data, comorbidity, fistula characteristics, fistula maturation and fistula complications were recorded and analyzed.Results: Of 344 patients enrolled, 156 (45.3%) received a lower arm AVF and 188 (54.7%) an upper arm AVF. Two hundred and seventy-six (80.2%) fistulas had a normal maturation. Lower arm AVF was a significant risk factor for non-maturation in this series (73.1% versus 86.2%; p = 0,0024). Female gender, diabetes and high age were not, but female gender showed a significant difference in distribution in upper arm versus lower arm fistulas (62.40% versus 37.6%; p = 0,0218).Conclusion: Careful clinical examination prior to upper or lower arm AVF creation together with the integration of risk assessment in the planning of AVF is worthwhile. A preference towards upper arm fistulas if major risk factors are present can improve overall maturation rates and lead to the same maturation rates as in the overall dialysis population. Therefore, the presence of risk factors for non-maturation should not lead to the underuse of native AVFs.

Balloon-Assisted Maturation (BAM) of the Arteriovenous Fistula: The Good, the Bad, and the Ugly

Arteriovenous fistula (AVF) maturation failure is currently a huge clinical problem. One approach to enhance the AVF maturation rate is an aggressive sequence of balloon angioplasty procedures, often known as balloon-assisted maturation. The goal of the current paper is to explore the pros and cons of this procedure and to try and better identify its impact on AVF maturation.