Outcome of a comprehensive follow-up program to enhance maturation of autogenous arteriovenous hemodialysis access

Outcome after early thrombotic occlusion of arteriovenous fistulas

OBJECTIVE

Arteriovenous fistulas (AVFs) are considered the first choice for venous access in end-stage renal disease patients, however, they are also known to have a high primary failure rate (early thrombosis and maturation failure). Of these, the outcome of thrombosed immature AVFs is not well known. This study aimed to investigate the outcome of AVFs with early thrombosis.

METHODS

Patients who underwent AVF creation from January 2009 to December 2019 at Seoul National University Hospital or Seoul Metropolitan Government - Seoul National University Boramae Medical Center were retrospectively reviewed. Patients who received salvage operations due to early thrombosis within 30 days after access creation were analyzed.

RESULTS

During the study period, a total of 45 patients (radiocephalic 26; brachiocephalic 19) developed early thrombosis and underwent salvage operations. The median age of patients was 61.0 (54.5-69.5) years, and 51.1% were male. The first salvage operation was performed on the median 1.0 (0.0-4.5) day after AVF creation. The most common cause for early thrombosis was venous stenosis (64.4%) and followed by poor arterial inflow (28.9%), especially in radiocephalic AVFs. About 20 AVFs were salvaged to maturation (46.5%). Post-salvage primary patency and secondary patency at 1 year was 72.6% and 100%. In a multivariate logistic regression, significant risk factors for maturation failures were minimum venous outflow diameter ⩽2.5 mm (OR, 4.433; 95% CI, 1.039-18.921; p = 0.044) and lower in patients with hypertension (OR, 0.064; 95% CI, 0.006-0.637; p = 0.019).

CONCLUSIONS

Thrombosed immature AVFs are associated with a high failure rate after salvage operation. However, if the salvage operation is successfully performed, it is associated with an acceptable 1-year outcome.

Upper limb exercise for arteriovenous fistula maturation in people requiring permanent haemodialysis access

BACKGROUND

The failure of arteriovenous fistulas (AVF) to mature is a major problem in patients with kidney failure who require haemodialysis (HD). Preoperative planning is an important factor in increasing functional AVF. Upper limb exercise has been recommended to gain AVF maturation. Studies of pre- and post-operative upper limb exercises in patients with kidney failure patients have been reported; however, the optimal program for this population is unknown due to inconsistent results among these programs.

OBJECTIVES

We aimed to determine if upper limb exercise would be beneficial for AVF maturation (prior to and post AVF creation) in patients with kidney failure and to improve AVF outcomes. This review also aimed to identify adverse events related to upper limb exercise.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 15 March 2022 through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov, and other resources (e.g. reference list, contacting relevant individuals, and grey literature).

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs, comparing upper limb exercise training programs with no intervention or other control programs before or after AVF creation in patients with kidney failure. Outcome measures included time to mature, ultrasound and clinical maturation, venous diameter, blood flow in the inflow artery, dialysis efficacy indicator, vascular access function (functional AVF), vascular access complications, and adverse events.

DATA COLLECTION AND ANALYSIS

Study selection and data extraction were taken by four independent authors. Bias assessment and quality assessment were undertaken independently by two authors. The effect estimate was analysed using risk ratio (RR) with 95% confidence intervals (CI) for dichotomous data, or mean difference (MD) or standardised mean difference (SMD) for continuous data. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

Nine studies (579 participants) were included, and seven studies (519 participants) conducting post-operative exercise training could be meta-analysed. Three comparisons were undertaken: (i) isotonic exercise training versus no intervention; (ii) isometric versus isotonic exercise training; and (iii) isotonic (high volume) versus isotonic exercise training (low volume). Due to insufficient data, we could not analyse pre-operative exercise training. Overall, the risk of bias was low for selection and reporting bias, high for performance and attrition bias, and unclear for detection bias. Compared to no intervention, isotonic exercise training may make little or no difference to ultrasound maturation (2 studies, 263 participants: RR 1.09, 95% CI 0.94 to 1.25; I² = 0%; low certainty evidence), but may improve clinical maturation (2 studies, 263 participants: RR 1.14, 95% CI 1.02 to 1.27; I² = 0%; low certainty evidence). Compared to isotonic exercise training, isometric exercise training may improve both ultrasound maturation (3 studies, 160 participants: RR 1.56, 95% CI 1.21 to 2.00; I² = 22%; low certainty evidence) and clinical maturation (3 studies, 160 participants: RR 1.80, 95% CI 1.18 to 2.76; I² = 53%; low certainty evidence). Venous diameter (3 studies, 160 participants: MD 0.84 mm, 95% CI 0.45 to 1.23; I² = 0%; low certainty evidence) and blood flow in the inflow artery (3 studies, 160 participants: MD 140.62 mL/min, 95% CI 38.72 to 242.52; I² = 0%; low certainty evidence) may be greater with isometric exercise training. It is uncertain whether isometric exercise training reduces vascular access complications (2 studies, 110 participants: RR 2.54, 95% CI 0.38 to 17.08; I² = 47%; very low certainty evidence). It is uncertain whether high volume isotonic exercise training improves venous diameter (2 studies, 93 participants: MD 0.19 mm, 95% CI -0.75 to 1.13; I² = 34%; very low certainty evidence) or blood flow in the inflow artery (1 study, 15 participants: MD -287.70 mL/min, 95% CI -625.99 to 60.59; very low certainty evidence) compared to low volume isotonic exercise training. None of the included studies reported time to mature, dialysis efficacy indicator, vascular access function, or adverse events.

AUTHORS' CONCLUSIONS

Our findings suggest that the current research evidence examining upper limb exercise programs is of low quality, attributable to variability in the type of interventions used and the overall low number of studies and participants.

Arteriovenous Fistula Maturation, Functional Patency, and Intervention Rates

Importance

National initiatives have emphasized the use of autogenous arteriovenous fistulas (AVFs) for hemodialysis, but their purported benefits have been questioned.

Objective

To examine AVF usability, longer-term functional patency, and remedial procedures to facilitate maturation, manage complications, or maintain patency in the Hemodialysis Fistula Maturation (HFM) Study.

Design, Setting, and Participants

The HFM Study was a multicenter (n = 7) prospective National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases cohort study performed to identify factors associated with AVF maturation. A total of 602 participants were enrolled (dialysis, kidney failure: 380; predialysis, chronic kidney disease [CKD]: 222) with AVF maturation ascertained for 535 (kidney failure, 353; CKD, 182) participants.

Interventions

All clinical decisions regarding AVF management were deferred to the individual centers, but remedial interventions were discouraged within 6 weeks of creation.

Main Outcomes and Measures

In this case series analysis, the primary outcome was unassisted maturation. Functional patency, freedom from intervention, and participant survival were summarized using Kaplan-Meier analysis.

Results

Most participants evaluated (n = 535) were men (372 [69.5%]) and had diabetes (311 [58.1%]); mean (SD) age was 54.6 (13.6) years. Almost two-thirds of the AVFs created (342 of 535 [64%]) were in the upper arm. The AVF maturation rates for the kidney failure vs CKD participants were 29% vs 10% at 3 months, 67% vs 38% at 6 months, and 76% vs 58% at 12 months. Several participants with kidney failure (133 [37.7%]) and CKD (63 [34.6%]) underwent interventions to facilitate maturation or manage complications before maturation. The median time from access creation to maturation was 115 days (interquartile range [IQR], 86-171 days) but differed by initial indication (CKD, 170 days; IQR, 113-269 days; kidney failure, 105 days; IQR, 81-137 days). The functional patency for the AVFs that matured at 1 year was 87% (95% CI, 83.2%-90.2%) and at 2 years, 75% (95% CI, 69.7%-79.7%), and there was no significant difference for those receiving interventions before maturation. Almost half (188 [47.5%]) of the AVFs that matured had further intervention to maintain patency or treat complications.

Conclusions and Relevance

The findings of this study suggest that AVF remains an accepted hemodialysis access option, although both its maturation and continued use require a moderate number of interventions to maintain patency and treat the associated complications.

Repeated Endovascular Interventions Are Worthwhile, Even After Thrombosis, to Maintain Long-Term Use of Autogenous Dialysis Fistulas

OBJECTIVES

Patients often require multiple access re-interventions to improve fistula patency and the overall usable lifespan of autogenous arteriovenous fistula (aAVF). There is no consensus on the appropriate number of re-interventions after which an access should be abandoned and new access placed. We evaluated whether repeated endovascular interventions for failing/failed aAVF are worthwhile or futile.

METHODS

A retrospective review was performed on aAVFs created between 2009-2014. Fistula function was evaluated until January 2017. Functional fistula patency (FFP) was defined as the total time of functional fistula use for hemodialysis, from time of cannulation to time of measurement or fistula abandonment, including all interventions performed to maintain/reestablish patency. Primary outcomes were FFP duration and number of post-dialysis interventions.

RESULTS

The study included 163 patients. Mean age was 67 (SD = 15.03). The only variable statistically different between functional fistulas and abandoned fistulas was obesity (p = 0.03). At the end of the study period, 145 (89.0%) patients continued to have functional fistulas, and 73 (44.8%) patients died, but had functional fistulas at time of death. Median FFP for the functional group was 3.18 years (range 0.01-7.01 years) and median number of interventions was 1 (range 0-13). In 18 patients (11%), the fistula was abandoned, most commonly due to thrombosis (47.1%), followed by infection (23.5%). No fistula was abandoned because of an unacceptable rate of reintervention. Median FFP in the abandoned group was 0.91 years (range 0.03-5.30 years), and median number of interventions was 0 (range of 0-5).

CONCLUSIONS

Through repeated interventions on aAVFs, none of the patients in our study exhausted all hemodialysis access options prior to transplantation, death or loss to follow-up. These results may indicate repeated and/or more frequent revisions do not negatively affect the FFP nor do they increase the overall risk for abandonment of aAVFs.

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.

Hemodialysis vascular access in the elderly-getting it right

Choosing the optimal hemodialysis vascular access for the elderly patient is best achieved by a patient-centered coordinated multidisciplinary team approach that aligns the patient's end-stage kidney disease Life-Plan, i.e., the individual treatment approach (supportive care, time-limited or long-term kidney replacement therapy, or combination thereof) and selection of dialysis modality (peritoneal dialysis versus hemodialysis) with the most suitable dialysis access. Finding the right balance between the patient's preferences, the likelihood of access function and survival, and potential complications in the context of available resources and limited patient survival can be extremely challenging. The framework for choosing the most appropriate vascular access for the elderly presented in this review considers the individual end-stage kidney disease Life-Plan, the patient life expectancy, the likelihood of access function and survival, the timing of dialysis relative to access placement, prior access history, and patient preference. This complex decision-making process should be dynamic in order to accommodate patients' changing needs and life and health circumstances. Effective and timely communication between the patient, their caregivers, and treating team is key to delivering truly patient-centered care. Delivering this care also requires overcoming the limitations of the currently available evidence that is predominantly based on observational data with its inherent risks of bias. While challenging, future randomized controlled studies exploring the risks, benefits, costs, and timing of placement of available access types in the elderly are required to help us "get it right" for our patients.

Relationships Between Clinical Processes and Arteriovenous Fistula Cannulation and Maturation: A Multicenter Prospective Cohort Study

BACKGROUND

Half of surgically created arteriovenous fistulas (AVFs) require additional intervention to effectively support hemodialysis. Postoperative care and complications may affect clinical maturation.

STUDY DESIGN

Hemodialysis Fistula Maturation (HFM) Study, a 7-center prospective cohort study.

SETTING & PARTICIPANTS

491 patients with single-stage AVFs who had neither thrombosis nor AVF intervention before a 6-week postoperative ultrasonographic examination and who required maintenance hemodialysis.

PREDICTORS

Postoperative care processes and complications.

OUTCOMES

Attempted cannulation, successful cannulation, and unassisted and overall clinical maturation as defined by the HFM Study criteria.

RESULTS

AVF cannulation was attempted in 443 of 491 (90.2%) participants and was eventually successful in 430 of these 443 (97.1%) participants. 263 of these 430 (61.2%) reached unassisted and 118 (27.4%) reached assisted AVF maturation (overall maturation, 381/430 [88.6%]). Attempted cannulation was less likely in patients of surgeons with policies for routine 2-week versus later-than-2-week first postoperative visits (OR, 0.21; 95% CI, 0.06-0.70), routine second postoperative follow-up visits (OR, 0.39; 95% CI, 0.15-0.97), and a routine clinical postoperative ultrasound (OR, 0.28; 95% CI, 0.14-0.55). Attempted cannulation was also less likely among patients undergoing procedures to assist maturation (OR, 0.51; 95% CI, 0.27-0.98). Unassisted maturation was more likely for patients treated in facilities with access coordinators (OR, 1.91; 95% CI, 1.17-3.12), but less likely after precannulation nonstudy ultrasounds (OR per ultrasound, 0.42 [95% CI, 0.26-0.68]) and initial unsuccessful cannulation attempts (OR per each additional attempt, 0.90 [95% CI, 0.83-0.98]). Overall maturation was less likely with infiltration before successful cannulation (OR, 0.44; 95% CI, 0.22-0.89). Among participants receiving maintenance hemodialysis before AVF surgery, unassisted and overall maturation were less likely with longer intervals from surgery to initial cannulation (ORs for each additional month of 0.81 [95% CI, 0.76-0.88] and 0.93 [95% CI, 0.89-0.98], respectively) and from initial to successful cannulation (ORs for each additional week of 0.87 [95% CI, 0.81-0.94] and 0.88 [95% CI, 0.83-0.94], respectively).

LIMITATIONS

Surgeons' management policies were assessed only by questionnaire at study onset. Most participants received upper-arm AVFs, planned 2-stage AVFs were excluded, and maturation time windows were imposed. Some care processes may have been missed and the observational design limits causal attribution.

CONCLUSIONS

Multiple processes of care and complications are associated with AVF maturation outcomes.

Predicting Arteriovenous Fistula Maturation with Intraoperative Blood Flow Measurements

Objective

To establish the criteria for intraoperative blood flow measurements taken at the time of autologous arteriovenous fistula (AVF) construction to predict future access maturation and thereby avoid waiting periods for futile fistulas to declare themselves.

Methods

From April 2006 through to March 2007 consecutive patients undergoing native AVF construction at one institution underwent intraoperative measurements of blood flow using transit-time ultrasound technology. No action was taken based upon the flow measurement at the time of surgery. Patients were followed and data collected comprising demographics and AVF maturation. A fistula was considered mature when it was successfully accessed for hemodialysis (HD) at least three times. Statistical analysis was performed including receiver operating characteristics (ROC), ANOVA, and Chi square using the JMP software package.

Results

During the 12-month period, 70 autologous AVFs were created including 41 antecubital brachiocephalic, 21 radiocephalic, and 8 basilic vein transpositions in 35 females and 33 males with a mean age of 58 ± 1.7 (mean ± SEM). The group included 37 Hispanic, 17 Native American, 10 Caucasian, 3 African American and 1 Asian patient. The etiology of renal failure comprised 53 diabetics, 13 hypertensives, 1 polycystic kidney disease and 1 congenital abnormality. Complete follow-up was available in 69/70 AVFs in 67 patients. Patients were excluded from analysis if they had not yet started dialysis (n=12), stopped or died (n=4) before their fistula was accessed. Patients whose AVFs were patent, but required a secondary procedure to achieve a functional access were considered non-functional. There was a significant difference between the maximal intraoperative flow rates between functional and non-functional AVFs (573.6 ± 103 mL/min vs. 216.8 ± 35.8 mL/min; p<0.05). There was no difference between groups in regard to age, gender, race or etiology of renal failure. ROC analysis suggested a threshold value of 140 mL/min for radiocephalic and 308 mL/min for brachiocephalic AVFs to predict maturation to a functional access.

Conclusion

Intraoperative blood flow measurements obtained at the time of autologous AVF construction can identify fistulas that are unlikely to mature; and therefore, that require immediate revision or abandonment which will ultimately expedite the establishment of a useful access in the HD patient. This is the first study to establish the minimal flow values uniquely needed for both radial artery and brachial artery AVFs to expect primary maturation to a functional access.

Long-Term Outcome of Upper Extremity Arteriovenous Fistula using pSLOT: Single-Center Longitudinal follow-up using a Protocol-Based Approach

Introduction

Functional arteriovenous fistula (AVF) is the best vascular access for end-stage renal disease patients. AVF maturation is variable and many require additional interventions to achieve functionality. Long-term benefits of such interventions are unclear. Using a protocol for AVF planning, creation, maturation evaluation and performing interventions based on objective findings along with maintaining a database on follow-up is necessary to evaluate this question. The aim of this study is to evaluate the long-term outcome of newly constructed AVFs using a protocol-based approach in a tertiary care academic center.

Methods

This is an observational study. Long-term outcomes of consecutive AVFs placed over a 5-year period using a protocol for creation, maturation evaluation and interventions based on objective findings were analyzed using a prospectively maintained clinical database.

Results

Functioning AVFs were achieved in 86.5% (n = 296) of 342 patients. Primary and secondary patency of 372 AVF procedures at 12, 24 and 60 months were 42.8%, 31.6% and 20.8%; and 81.8%, 77.6% and 71.7%, respectively. Functional patency at 12, 24 and 60 months were 95.1%, 88.7%, and 85.2%, respectively. Long-term function was similar for AVFs maturing with ≤4 interventions and without interventions. AVFs maturing with 2-4 interventions needed significantly more interventions to maintain long-term functional patency (p = 0.003).

Conclusions

Piggyback straight-line on-lay technique (pSLOT) improves early outcome providing opportunity to identify other problems contributing to non-maturation. A large number of AVFs needing planned interventions to mature provide good long-term function. Establishing process of care guidelines for creation and follow-up has a potential to improve AVF outcome.

Endovascular treatment to boost AV fistula maturation

Impaired fistula maturation is associated with puncture-related complications, insufficient dialysis and potential permanent access failure. Non-maturation is frequently initiated by stenotic vascular access vessels comprising the outflow veins, the arteriovenous anastomosis and infrequently the inflow artery. Further findings in maturation protraction are central venous stenoses or accessory outflow veins. Depending on the underlying pathology, several endovascular approaches to boost fistula maturation are possible. To date standard balloon angioplasty remains the primary proven treatment option.

Optiflow anastomotic device for hemodialysis vascular access creation

The need to have consistent methods and consistent technique to optimize hemodialysis outcomes is behind the concept of the Optiflow™ device. This device was created to allow for consistency in size of the arterial anastomosis and consistency in angle of the vein to the artery at the anastomosis. Early data suggest that allowing these two technical entities can improve outcomes in regards to flow and maturity in arteriovenous fistula creation. This article is a summary of early data that demonstrate the impact the Optiflow device on brachial cephalic fistulas.

Percutaneous Endovascular Treatment to Salvage Non-Maturing Arteriovenous Fistulas in a Multiethnic Asian Population

Introduction: An arteriovenous fistula (AVF) is the preferred method for haemodialysis in patients with end-stage renal failure. Previous studies have shown value in attempting percutaneous transluminal angioplasty (PTA) to salvage AVFs that fail to mature, but they are relatively small in size and mainly reported in Western populations. We reviewed our data of PTA in non-maturing AVFs to establish whether this technique is translatable to our local multiethnic population. Materials and Methods: We retrospectively reviewed the medical records and procedural images of 105 patients who had PTA for non-maturing AVFs performed at our department from January 2008 to January 2011. Technical success was defined as ≤30% residual stenosis after angioplasty. Clinical success was defined as at least 1 successful haemodialysis session within 4 weeks after PTA. Results: All 105 patients underwent angioplasty for at least 1 haemodynamically significant stenosis. Six (5.7%) had additional embolisation of accessory veins. Technical success was achieved in 95.2% of cases. The clinical success rate was 76.2%. Primary patency rates at 3, 6 and 12 months were 83%, 45% and 28%, respectively. Secondary patency rates at 3, 6 and 12 months were 90%, 79% and 70%, respectively. The minor complication rate was 18.1%. No major complications were encountered. An average of 1.7 interventions per access-year was required to maintain AVF patency. Patients with a preoperative vein size >2.0 mm and age <55 years were more likely to achieve clinical success, although not statistically significant. Conclusion: PTA is a viable option to help salvage non-maturing AVFs in a multiethnic Asian population. Key words: Angioplasty, Chronic renal disease, Haemodialysis, Interventional radiology

The Clinical Efficacy of Balloon-Assisted Maturation of Autogenous Arteriovenous Fistulae

BACKGROUND

Delayed maturation of arteriovenous fistulae (AVF) among patients who require hemodialysis (HD) can lead to catheter sepsis with its resultant morbidity and mortality. Some have proposed that sequential balloon-assisted maturation (BAM) may accelerate the maturation times of these accesses. On the other hand, serial balloon angioplasty of normal vein may result in stenosis and delay maturation. Although the safety of BAM has been shown, direct comparison to nonmatured AVF has not been explored. Therefore, we conducted a retrospective analysis of our prospectively maintained vascular access database to compare the duration of period to AVF maturation between patients who received BAM and those who were not referred for BAM at our institution.

METHODS

Prospectively collected data over a 3-year period in 194 patients who underwent AVF creation at our institution were retrospectively analyzed. The duration to maturation of the AVF was determined by comparing the period between the creation of the fistula and the first successful cannulation of the fistula. Only patients on HD were included. Patients who underwent BAM or placement of AVF at an outside institution were excluded. Follow-up consisted reviewing of postoperative AVF duplex for patency, hospital and clinic databases, HD center databases, and telephone interviews.

RESULTS

Of the 194 patients who had AVF placement, 172 patients were on HD within 2 weeks of AVF placement, whereas 22 patients had AVF placed in anticipation of the need for HD. Of the 172 patients on HD within 2 weeks, 54 patients had BAM performed at our institution and 4 patients had BAM at an outside institution, whereas 114 patients were not referred for BAM. Thirty-three of these 114 patients were age and gender matched to compare to the patients who underwent BAM at our institution. At the time of this analysis, of the 54 patients who had BAM, 30 had functional AVF (19 men, 11 women; mean age, 62 years; range, 26-86 [standard deviation, SD ± 18] years). In the BAM group of functioning AVF, n = 30, the total number of procedures was 125 (range, 1-8, average 4). The overall average duration to maturation of the AVF was 119 days (SD ± 84 days) and 146 days (SD ± 157 days) P = 0.73, for BAM and non-BAM, respectively.

CONCLUSIONS

These preliminary data suggest the role of BAM did not decrease maturation times of AVF and that BAM warrants further scrutiny before further adoption.

Arteriovenous Access Failure, Stenosis, and Thrombosis

Vascular access–related complications can lead to patient morbidity and reduced patient quality of life. Some of the common arteriovenous access complications include failure to mature, stenosis formation, and thrombosis.

New Insights into Dialysis Vascular Access: What Is the Optimal Vascular Access Type and Timing of Access Creation in CKD and Dialysis Patients?

Optimal vascular access planning begins when the patient is in the predialysis stages of CKD. The choice of optimal vascular access for an individual patient and determining timing of access creation are dependent on a multitude of factors that can vary widely with each patient, including demographics, comorbidities, anatomy, and personal preferences. It is important to consider every patient's ESRD life plan (hence, their overall dialysis access life plan for every vascular access creation or placement). Optimal access type and timing of access creation are also influenced by factors external to the patient, such as surgeon experience and processes of care. In this review, we will discuss the key determinants in optimal access type and timing of access creation for upper extremity arteriovenous fistulas and grafts.

Compliance with surgical follow-up does not influence fistula maturation in a county hospital population

BACKGROUND

The purpose of this study is to examine follow-up rates and maturation rates after dialysis access surgery using a fistula-first approach in a county hospital with an indigent population.

METHODS

A prospectively maintained dialysis access database was queried for cases performed between August 1, 2009 and September 30, 2011. The follow-up period ended on December 31, 2011. An attempt was made to contact patients who did not have complete follow-up data recorded to the point of fistula maturation for arteriovenous fistulas (AVF). Patients were contacted directly or through their dialysis center. Maturation was defined by successful use of the AVF for hemodialysis for at least 2 weeks for patients who are dialysis dependent or by the clinical assessment of an attending vascular surgeon for those not on dialysis.

RESULTS

Two hundred three dialysis access cases were performed. The mean age was 51.4 years. One hundred twenty-six (62%) were male and 175 (86%) were Hispanic. Of these, 194 (95.6%) were AVF. Three AVF were ligated in the postoperative period for steal. Of the remaining 191 AVF, 94 (49%) patients completed their scheduled follow-up appointments. Sixty-six (35%) patients did not come to clinic but were contacted. Twenty-six (14%) patients were completely lost to follow-up and 5 (2.6%) died. Maturation data was obtained on 160 AVF. Of those, 123 (77%) reached maturation with a mean maturation time of 112 ± 99 days (range, 21-483). Twenty patients who completed follow-up underwent at least 1 additional surgical or endovascular procedure in an attempt to achieve maturation. Seventeen (85%) patients who underwent a secondary procedure went on to achieve maturation. There was no significant difference in maturation between the group that completed follow-up and those who were contacted by phone (69 [73%] vs. 54 [81%], P = not significant).

CONCLUSIONS

In this indigent population, follow-up does not influence maturation rates of AVF. Despite poor compliance with follow-up in the setting of a public hospital, the maturation rate of an aggressive fistula-first approach is acceptable.

Arteriovenous Fistula Creation Using the Optiflow™ Vascular Anastomotic Connector: The Open (Optiflow PatEncy and MaturatioN) Study

Purpose

Arteriovenous fistulas (AVFs) are the preferred form of vascular access for hemodialysis. However, non-maturation and patency are major clinical problems. The Optiflow™ device is an implantable anastomotic connector used to standardize the creation of an AVF. Studies have suggested that the geometry of the anastomosis and experience of the surgeon impact patency and maturation rates. The Optiflow serves as a surgical template whereby the geometry and flow path of the anastomosis are predetermined. This prospective study was intended to evaluate maturation, patency and safety of the Optiflow.

Methods

Forty-one upper arm AVFs were created in 41 end-stage renal disease patients using the Optiflow device at two investigational sites. Patients were followed for 90 days with serial Doppler ultrasounds performed at approximately 14, 42 and 90 days to determine AVF maturation. The primary performance endpoint was unassisted maturation, defined as an outflow vein that was equal to or greater than 5 mm in diameter, and with flow equal to or greater than 500 mL/min without the need for any intervention intended to promote or maintain maturation. The primary safety endpoint was the rate of device-related serious adverse events.

Results

Unassisted maturation rates were 76%, 72% and 68% and unassisted patency rates were 93%, 88% and 78%, at 14, 42 and 90 days, respectively. There were no device-related serious adverse events.

Conclusions

The results suggest that the Optiflow is safe for its intended use and could play an important role in enhancing AVF maturation while standardizing the anastomotic technique.

[Placement of a native arteriovenous access]

The epidemically increasing number of diabetics is resulting in an increasing number of patients with end-stage renal failure who, furthermore, show a high degree of co-morbidity. An increasingly longer survival time with dialysis also means that the group of patients requiring functional dialysis access is continuously growing. The autologous arteriovenous fistula with its high function and low complication rate is the best access form, and should be provided to as many of those patients requiring dialysis as possible. This article discusses the timing of dialysis access, the importance of the medical history and the physical examination, preoperative investigation of the prospective fistula vein, the possibilities of anastomosis, maturation of the fistula and long-term results.

Complications of arteriovenous fistula for hemodialysis: an 8-year study

BACKGROUND

To assess the frequency and characteristics of complications of arteriovenous fistula (AVF) and their effect on fistula outcome.

METHODS

We retrospectively reviewed 628 AVFs constructed from November 2002 to October 2010 to record the complications and their management options. The association between age, sex, comorbidities (HIV, hypertension, and diabetes), fistula type, and complications was sought.

RESULTS

Most patients were males (73.7%). The mean age was 45.3 years. Comorbidities seen included diabetes mellitus (22.12%), hypertension (83.12%), and HIV infection (9.87%). AVFs constructed were mainly radiocephalic (68%) and brachiocephalic (24.9%). The median follow-up period was 275 days. The cumulative patency rate was 76% and 51% at 1 year and 2 years, respectively. Altogether, 211 complications occurred in 16% of the AVFs. Among them, 36.96% were severe, 25.11% moderate, and 43.91% minor. With respect to the time of occurrence, 63.98% were late complications, 12.79% immediate, and 23.22% early. Aneurysms, failure to mature, and thrombosis were the most frequent complications occurring in 26.54%, 14.69%, and 12.79% of cases, respectively. The management options for the complications included the creation of a new access in 36.96%, a temporary catheter before a new AVF in 10.52%, and nonoperative management in 43.12%. We found no adverse effect of comorbid factors such as diabetes mellitus (χ(2) = 3.58, P > 0.05) or HIV-positive status (χ(2) = 0.64, P > 0.05) on the complication rate.

CONCLUSION

This study shows an overall frequency of complications of 16%. These results show the potential for low complication rate of AVF in selected population.

Vascular access surveillance: an ongoing controversy

Hemodialysis vascular access surveillance continues to be widely recommended despite ongoing controversy as to its benefit in prolonging access patency compared with clinical monitoring alone. The most common screening tests are access blood flow and dialysis venous pressure measurements. When surveillance test results cross a predetermined threshold, accesses are referred for intervention with correction of stenosis to reduce future thrombosis and prolong access survival. Current surveillance strategies have four components: (1) underlying condition; (2) screening test; (3) intervention; and (4) outcomes. However, limitations exist within each component that may prevent achieving the desired outcomes. This review discusses these limitations and their consequences. To date, randomized controlled trials have not consistently shown that surveillance improves outcomes in grafts, and there is limited evidence that surveillance reduces thrombosis without prolonging the life of native fistulae. In conclusion, current evidence does not support the concept that all accesses should undergo routine surveillance with intervention.