Factors predicting failure of AV “fistula first” policy in the elderly

An arteriovenous fistula (AVF) is the preferential hemodialysis (HD) access. The goal of this study was to identify factors associated with pre‐dialysis AVF failure in an elderly HD population. We used United States Renal Data System + Medicare claims data to identify patients ≥67 years old who had an AVF as their initial vascular access placed pre‐dialysis. Failure of the AVF to be used for initial HD, was used as the outcome. Logistic regression model was used to identify factors associated with AVF failure. The study cohort consisted of 20,360 subjects (76.2 ± 6.02 year old, 58.5% men). Forty‐eight percent of patients initiated dialysis using an AVF, while 52% used a catheter or an AVG. The following variables found to be associated with AVF failure when an AVF was created at least 4 months pre‐HD initiation: older age (odds ratio [OR] 1.01; 95% confidence interval [CI] 1.00–1.02), female gender (OR 1.69; 95% CI 1.55–1.83), black race (OR 1.41; 95% CI 1.26–1.58), history of diabetes (OR 1.22; 95% CI 1.06–1.39), cardiac failure (OR 1.26; 95% CI 1.15–1.37), and shorter duration of pre–end‐stage renal disease (ESRD) nephrology care (OR for a nephrology care of less than 6 months prior to ESRD of 1.22 compared with a pre‐ESRD nephrology follow up of more than 12 months; 95% CI 1.07–1.38). OR for AVF failure for the entire cohort showed similar findings. In an elderly HD population, there is an association of older age, female gender, black race, diabetes, cardiac failure and shorter pre‐ESRD nephrology care with predialysis AVF failure.     

Disparities in arteriovenous fistula placement in older hemodialysis patients

The benefits of an arteriovenous fistula (AVF) as the preferred vascular access for hemodialysis have been clearly demonstrated. However, only about 20% of patients in the United States initiate hemodialysis with an AVF. In this study, we assessed whether disparities exist in the type of first hemodialysis access placed prior to dialysis start (rather than that used at dialysis initiation), to detect whether certain disadvantaged groups might have lower likelihood of AVF placement. Study cohort of 118,767 incident hemodialysis patients ≥67 years of age (1/2005–12/2008) derived from the United States Renal Data System was linked with Medicare claims data to identify the type of initial access placed predialysis. We used logistic regression model with outcome being the initial predialysis placement of an AVF as opposed to an arteriovenous graft or a central venous catheter. Increasing age, female sex, black race, lower body mass index, urban location, certain comorbidities, and shorter pre–end‐stage renal disease nephrology care are all associated with a significantly lower likelihood of AVF placement as initial access predialysis. Our study suggests the presence of significant disparities in the placement of an AVF as initial hemodialysis vascular access. We suggest that additional attention should be paid to these patient groups to improve disparities by patient education, earlier referral, and close follow‐up.     

Safety of arteriovenous fistulae and grafts for continuous renal replacement therapy: The Michigan experience

Introduction: Arteriovenous fistula or graft (AVF/AVG) use is widely considered contraindicated for continuous renal replacement therapy (CRRT), yet insertion of hemodialysis (HD) catheters can carry high complication risk in critically ill end‐stage renal disease (ESRD) patients. Methods: Single‐center analysis of 48 consecutive hospitalized ESRD patients on maintenance HD who underwent CRRT using AVF/AVG from 2012 to 2013. Primary outcome was access‐related complications. Findings: Mean age was 60 years, 48% were male, and 88% required vasopressor support. Median duration of AVF/AVG use for CRRT was 4 days (range 1–34). Ten (21%) patients had access complications (5 bleeding, 5 infiltration, 1 thrombosis); 5 (10.4%) required catheter placement. Overall 31 (65%) patients survived to hospital discharge and AVF/AVG access was functional at the time of discharge in 29 (94%) patients. Discussion: In our experience, use of AVF/AVG for CRRT can be performed with a low serious complication rate and low risk of access loss, potentially avoiding catheter‐related complications.     

Barriers,biases, and beliefs about arteriovenous fistula placement in children: A survey of the International Pediatric Fistula First Initiative (IPFFI) within the Midwest Pediatric Nephrology Consortium (MWPNC)

There has been recent emphasis on increased arteriovenous fistula (AVF) use and decreased central venous catheter use in hemodialysis (HD) patients. The International Pediatric Fistula First Initiative was founded via collaborative effort with the Midwest Pediatric Nephrology Consortium to alert nephrologists, surgeons, and dialysis staff to consider fistulae as the best access in pediatric HD patients. A multidisciplinary educational DVD outlining expectations and strategies to increase AVF placement and usage in children was created. Participants were administered a survey previewing and postviewing to identify barriers to placement and usage of AVF in children. A total of 52 surveys were subdivided as either “dialysis staff” or “proceduralist” at five centers. Thirty‐three percent of respondents were unaware if their practice was following published guidelines. Sixty‐five percent of respondents stated they referred to a dedicated vascular access surgeon at their respective institutions. Methods used to monitor AVF function included physical exam, venous pressure monitoring, and ultrasound dilution. Vascular access was placed within 3 months in only 35% of patients. Interdisciplinary communication problems between surgeons, interventional radiologists, and nephrologists were identified as a major barrier. Lack of AVF usage was often due to maturation failure. Routine access rounds did not occur in any centers. Regarding monitoring, 74% of the respondents use physical exam, 26% use venous pressure monitoring, and 9% use ultrasound dilution. Ninety‐three percent of dialysis staff stated they would change practice patterns following the intervention; however, 12% of surgeons stated they would alter practice patterns. To our knowledge, this is the first report to identify barriers to placement of AVF in children from the perspectives of multidisciplinary team members including pediatric nephrologists, surgeons, interventional radiologists, and multidisciplinary dialysis staff.     

Hemodialysis access-related survival and morbidity in an elderly population in South West Thames, UK

Elderly patients form the most rapidly expanding group of hemodialysis (HD) patients in Europe and the United States. There are initiatives to promote an increase in arteriovenous fistula (AVF) formation. There are concerns that elderly patients may have lower rates of surgical vascular access compared with younger patients due to risks of higher co-morbidities, surgical complications, and higher AVF nonuse rates. The aim of this study was to compare access-related survival and morbidity for dialysis catheters and AVFs and to evaluate the AVF nonuse rate in an elderly population. We have performed a retrospective analysis of access survival and morbidity in patients > or = 70 years of age, either on maintenance HD or predialysis with preemptive formation of surgical access. One hundred and forty-six patients had permanent HD access created during the 18-month study period, from 1 January 2006 to June 2007. There were 89 male and 57 female patients in whom 78 AVFs and 137 tunneled venous catheters were inserted. There was a significantly greater loss of vascular access due to infection in the catheter group compared with the AVF group (P<0.016). Access survival was also significantly prolonged in the AVF group (446 days, 95% confidence interval 405-487) compared with the catheter group (276 days, 95% confidence interval 240-313), P=0.001. The rate of nonuse of AVFs was low (16%). We conclude that an AVF is the preferred form of vascular access in elderly HD patients.     

Usefulness of assisted procedures for arteriovenous fistula maturation without compromising access patency

Introduction: To increase the rate of arteriovenous fistula (AVF) use, assisted procedures for immature AVF have been strenuously performed. However, this is controversial in that an AVF matured by these assisted procedures may require more frequent intervention to maintain its patency, and have decreased long‐term patency. Methods: Eighty four AVFs that were matured with assisted maturation procedures and 266 AVFs that matured spontaneously without intervention, created between November 2009 and March 2013 from the hemodialysis (HD) vascular access (VA) cohort, were compared retrospectively and we also investigated the factors that may influence AVF long‐term patency. Median follow‐up was 26.8 months (interquartile range, 6.6–45.0 months). Findings: Access survival did not differ between AVFs matured by assisted procedures and spontaneously mature AVFs (P = 0.29). In multivariate Cox regression analysis of AVF survival, age (HR, 1.029; 95% CI, 1.004–1.056; P = 0.024), maturation without assisted procedures 4–6 weeks after AVF creation (HR, 0.233; 95% CI, 0.107–0.506; P < 0.001), and AVF thrombosis (HR, 26.511; 95% CI, 10.986–63.978; P < 0.001) were significantly associated with AVF survival. Performance of assisted procedures to induce AVF maturation did not influence AVF survival (HR, 0.437; 95% CI, 0.191–1.002; P = 0.05). Discussion: Our results support that idea that assisted maturation procedures can ensure the success of immature AVF without compromising long‐term patency. These procedures can be considered more positively for increasing AVF use for VA placement in HD patients.     

Urgent hemodialysis with the use of peripheral veins to avoid catheter insertion

Urgent hemodialysis (HD) in patients with uremia is usually performed using a central vein catheter unless an arteriovenous fistula (AVF) was created in the predialysis period. We present a unique approach, in a patient in whom the first two HD sessions were conducted without implantation of a catheter or AVF. The perfectly developed peripheral veins of a professional bodybuilder served as vascular access allowing catheter insertion to be avoided. The aim of this short case report is to recall a forgotten method for performing urgent HD in patients without a fistula, but with suitably enlarged superficial veins.     

The impact of arteriovenous fistula creation in pulmonary hypertension: Measurement of pulmonary pressures by right heart catheterization in a patient with respiratory failure following arteriovenous fistula creation

Pulmonary hypertension (PHT) is frequent in patients receiving hemodialysis (HD) and carries a high mortality. While it has been suggested that arteriovenous fistulae (AVF) may exacerbate PHT in HD patients, it has also been observed that creating AVF in patients with chronic lung disease and normal renal function may lead to improved exercise tolerance. Most of the observations regarding HD patients using echocardiography demonstrated that temporary closure of AVF improved pulmonary pressures. We present the case of a 45‐year‐old patient with chronic obstructive pulmonary disease on HD who experienced respiratory failure following AVF formation and underwent right heart catheterization. Severe PHT was diagnosed but transient occlusion of the fistula failed to improve the PHT. This case supports the theory that fistula creation does not exacerbate pre‐existing PHT and that AVF can be the access of choice in patients with known chronic lung disease and pulmonary hypertension.     

Why Do So Many Patients Have a Dialysis Catheter and Not Arteriovenous Fistulae or Grafts?

The Dialysis Outcome and Quality Initiative has guidelines for vascular access and states that the dialysis catheter (DC) should be limited to less than 20% of the end-stage renal disease (ESRD) patients. Our center has found this target difficult to achieve.
Objective:  We wondered what the reasons for use of a DC might be.
Methods:  We noted the number of patients with a DC in place and assessed the reasons why the DC was being used on 8/1/03.
Results:  73 of the 170 (42.9%) patients had a DC on 8/1/03. 24 (32.9%) of the patients refused to have initial arteriovenous fistulae or grafts (AVF/G) or a secondary AVF/G revision or replacement procedure performed after initial AVF/G failure. 15 (20.5%) patients had a maturing AVF/G, 12 (16.4%) had significant medical and/or surgical contraindications for AVF/G placement, 9 (12.3%) patients were awaiting surgical thrombectomy, revision or placement of AVF/G, 6 patients (8.2%) were awaiting transfer to CPD therapy, 4 (5.5%) patients were undecided about having an AVF/G placed, and 1 (1.4%) had acute renal failure and early ESRD recovery was expected. Only 2 (2.7%) patients had no access plan by the nephrology team.
Conclusions:  Patients' refusal for an AVF/G placement and patients with a maturing AVF/G or awaiting surgical revision or placement were the most common reasons for the use of a DC in our center. To significantly impact on the high use of the DC, it would be crucial to better understand the reasons for patients' refusals.     

Coronal mode ultrasound guided hemodialysis cannulation: A pilot randomized comparison with standard cannulation technique

Background: Infiltrations from cannulation result in significant morbidity including loss of hemodialysis (HD) vascular access (VA). Cannulation is dependent on personnel skill and VA characteristics. Surface marking of VA lacks real‐time information and traditional ultrasound (US) devices are large, expensive, requiring skilled operators. Sonic Window© (Analogic Ultrasound, Peabody, MA, USA) is a coronal mode ultrasound device (CMUD) approved for VA cannulation. Methods: Single center randomized, prospective pilot study comparing handheld US‐guided cannulation of new arteriovenous fistula (AVF) to standard cannulation practices. Patients with end stage renal disease (ESRD) on in‐center HD who had a new AVF cleared for cannulation and dialysis were enrolled. Patients with new AVF received either standard cannulation (control group) or image guidance using CMUD (study group) for 3 weeks. Ultrasound characteristics of VA, cannulation practices and complications end points were obtained. Results: An infiltration rate of 9.7% was noted during the study. Slightly lower odds ratio (OR) of infiltration was observed in the study group (OR 0.94, 95% CI: 0.26–3.41, P value = 0.93). Study group yielded longer time for assessment (101.8 ± 80.2 vs. 22.3 ± 22.5 seconds, P = < 0.001), increased cannulation time (41.1 ± 70.6 vs. 25.0 ± 27.9 seconds, P = 0.04), and increased patient satisfaction (94.6% vs. 82%, P = 0.04) compared to control group. Number of cannulation attempts, needle size, arterial or venous needle insertion, and tourniquet usage between groups were not statistically different. Conclusion: Handheld ultrasound is a safe and useful aid in cannulation of dialysis access.     

Creation of arteriovenous fistulae for hemodialysis in octogenarians

Elderly patients, defined as octogenarians and nonagenarians, are an increasing population entering renal replacement therapy. Advanced age appears as an exclusive factor negatively influencing dialysis practice. Elderly patients are referred late for the initiation of hemodialysis and more likely are offered catheters rather than arteriovenous fistulae (AVF), which increase mortality and negatively affect quality of life. We present our approach to the creation of vascular access for hemodialysis in this demanding population. In 2006–2012, 39 patients aged 85.9 ± 2.05 with end‐stage renal disease, mainly resulting from ischemic nephropathy, were admitted to the Department of Nephrology to establish permanent vascular access for hemodialysis: preferably AVF. Temporary dialysis catheters were implanted in uremic emergency to bridge the time to fistula creation/maturation. AVF was attempted in 87.2% of the patients. Primary AVF function was achieved in 54% of the patients. Cumulative proportional survival of AVF at months 12 and 24 was 81.5%. Ninety‐four percent of AVF were localized on the forearm: 74% in the distal and 20% in the proximal part. Mean duration of hemodialysis therapy was 20.80 ± 19.45 months. The mean time of AVF use was 15.9 ± 20.2 months. Until present, 38% have been dialyzed using AVF for 31.0 ± 18.8 months. Five patients died with functioning fistula. Eight patients initiated hemodialysis therapy with fistula. During further observation, the use of AVF increased to 62%. Elderly patients should not be denied creation of AVF as a rule. The outcome of AVF benefits more from acknowledging individual vascular conditions rather than age of the patient.     

Relationship of Hypoalbuminemia to Multiple Clinical Factors in Hemodialysis Patients

Research shows that low albumin is correlated with higher morbidity and mortality in the dialysis population. The reasons for this are multi‐factorial and may be related to inadequate protein intake, infection and sepsis, inadequate dialysis, or catabolism of uremia. USRDS data show that ESRD Network 16 tends to have lower albumins compared to other ESRD Networks. Objective: To evaluate albumin status of HD patients at Puget Sound Kidney Centers, Everett, WA (ESRD Network 16) and identify potential factors that may put patients at risk of hypoalbuminemia. Methods: Clinical and biochemical data were collected for 3 months on 221 HD patients. Data included serum albumin (bromcresol purple), calcium, phosphorus, CO₂, Hct, % saturation, ferritin, PTH, BUN, Kt/V, URR, nPCR, hours of HD treatment, interdialytic fluid weight gains, DW changes, incidence of infection and hospitalization, catheter use for dialysis access, presence of diabetes and other co‐morbidities, dialyzer reuse, social/psychological status, and use of nutrition supplements. All biochemical data were collected after the longest interdialytic period and analyzed at the same reference laboratory. Data were averaged for each patient for the 3 months and correlations between parameters were determined using Chi‐square analysis. Results: 25% of all patients had albumins <3.2 g/dL (reference range for normal population 3.5–5.0 g/dL). Patients with lower albumins were significantly more likely to have DM (p < 0.02), use catheters for HD access (p < 0.001), had infections during the previous month (p < 0.001), been hospitalized during the previous month (p < 0.002), have co‐morbid issues (p < 0.001), and use nutrition supplements (p < 0.002). No other factors were significantly correlated with lower albumin. Conclusion: Factors other than nutrition seem to be related to hypoalbuminemia. This study has prompted improved protocols for catheter care and use, infection control, and early intervention for nutrition supplement use. Increased screening and monitoring at‐risk patients (those with diabetes and other co‐morbid conditions) has resulted in improved patient care.     

Brachial‐cephalic fistula recovered with drainage for the basilic vein: Case report

Vascular access is essential for the implementation of hemodialysis (HD). The arteriovenous fistula (AVF) can be constructed in various locations using various veins. However, the quality of the veins will influence the construction site, as well as the functioning of the AVF. Careful analysis of the vascular network allows options for the development of new fistulas presentations. We present and discuss the case of a woman aged 69 years in HD in which a brachial‐cephalic fistula with drainage to basilic vein was created, through rotation of the cephalic vein on the forearm level. This kind of access serves to prolong the time spent dialyzing through native fistulae, with their reduced complications and greater cost‐effectiveness.     

Epidemiology and Blood Flow Surveillance of the Native Arteriovenous Fistula: A Review of the Recent Literature

Vascular access placement is a key management issue for hemodialysis patients. Despite being well regarded as the access of first choice, the native arteriovenous fistula (AVF) remains underutilized in the United States. The first part of this review examines recent epidemiology studies addressing patient factors associated with the use of the synthetic arteriovenous graft as opposed to the native fistula. Female gender and older age are consistently associated with a higher frequency of graft use. Diabetes, peripheral vascular disease, and body mass index were associated with graft use in some but not all of the studies. Recent evidence also suggests an independent survival advantage for patients dialyzing via native fistulae especially for infection-related mortality. The second part reviews evidence surrounding the recommendations for blood flow surveillance of the native fistula. The hemodynamic features of the native fistula are examined and differences from synthetic grafts are highlighted. Clinical studies assessing the use of blood flow surveillance to prevent the sudden thrombosis of native fistulae are reviewed. Blood flow thresholds for further investigation are yet to be determined definitely for AVF and randomized studies should be performed to assesses the impact on AVF thrombosis rates.     

High rate of fistula placement in a cohort of dialysis patients in a single payer system

Arteriovenous fistulas (AVFs) are considered superior to arteriovenous grafts and catheters. Nevertheless, AVF prevalence in the United States remains under the established target. The complication rates and financial cost of vascular access continue to rise and disproportionately contribute to the burgeoning health care costs. The relationship between financial incentives for a type of vascular access and rate of access placement is unclear. All chronic hemodialysis patients (n=99) receiving care at Philadelphia Veterans Affairs Medical Center as of August 1, 2008 were participants. Demographic characteristics, vascular access type, and nonrelative value unit compensation were assessed as predictors, and the vascular access prevalence rate, operative times, and frequency of access interventions were analyzed. A 73.7% AVF rate was achieved in this cohort of patients with 51.5% diabetes mellitus. The number of access procedures per patient per year remained constant over time. The Philadelphia Veterans Affairs Medical Center, a single payer system, achieved superior AVF prevalence and exceeded the national AVF target. Financial incentives for arteriovenous graft placement currently exist in the United States, as there is similar Medicare reimbursement for arteriovenous graft and basilic vein transposition, despite longer operative times for basilic vein transpositions. The high AVF prevalence at the Philadelphia Veterans Affairs Medical Center may be due to the VA nonrelative value unit‐driven system that allows for interdisciplinary care, priority of AVFs, and frequent use of basilic vein transposition surgery, when appropriate. We have identified an important, hypothesis‐generating example of a nonrelative value unit‐based approach to vascular access yielding superior results with respect to patient care and cost.     

Refractory orthostatic hypotension after creation of a brachio‐basilic arteriovenous fistula

Arteriovenous fistulas (AVFs) are preferred vascular access in patients with end‐stage renal disease (ESRD) undergoing hemodialysis (HD). However, AVFs, can occasionally lead to clinically significant complications. Of these, cardiovascular complications have been well described in the literature. In this report, we describe a case of a 78‐year‐old Caucasian male with ESRD who presented with severe debilitating dizziness and orthostatic hypotension that started soon after the creation of left brachiobasilic AVF. The patient had no significant cardiovascular history apart from essential hypertension. His symptoms persisted despite extensive evaluation and interventions, and abated only after banding of the AVF. This report describes the timeline of the patient's clinical course beginning from the day of creation of his AVF, through the course of his hospitalization leading to AVF banding and ending with postoperative recovery phase with resolution of symptoms. We will also review the pathophysiologic effects of AVF on cardiovascular system, as well as the potential causes of our patient's clinical presentation.     

Relation between Access-Related Infection and Preinfection Serum Albumin Concentration in Patients on Chronic Hemodialysis

Background: Hemodialysis (HD) access‐related infection is a major cause of morbidity and mortality in HD patients. We tested whether hypoalbuminemia is a risk factor for HD access infection and whether mortality of HD catheter infection is affected by removal of the infected catheter. Methods: We analyzed the records of 87 patients on chronic HD who were hospitalized for HD access‐related infection. We obtained data on age, sex, preinfection serum albumin level, comorbidities, complications, infecting organism, type of infection, mode of management, and mortality. We compared preinfection serum albumin levels in 79 patients with HD access infection with the serum albumin levels of 198 control patients on chronic HD without HD access infection admitted to the hospital during the same time for other reasons. In the HD catheter infection subgroup, we compared mortalities between patients treated with catheter removal plus antibiotics as the primary mode of management and those treated initially with antibiotics alone. Results: Preadmission serum albumin level was lower in the HD access infection group (2.4 ± 0.6 g/dL) than in the control group (3.2 ± 0.6 g/dL, P < 0.0001). Logistic regression identified preadmission serum albumin level as a strong independent predictor of HD access infection. In a logistic regression model, with age, sex, HIV status, diabetes, and type of HD vascular access (excluding arterovenous fistula) as the covariates, the odds ratio of HD access infection was 9.8 (95% confidence interval [CI] 4.9–19.7) for a serum albumin level ≤ 3.0 g/dL (P < 0.0001), 10.4 (95% CI 4.97–21.6) for a serum albumin level ≤ 2.5 g/dL (P < 0.0001), and 28.0 (95% CI 5.8–135.9) for a serum albumin level ≤ 2.0 g/dL (P < 0.0001). Case mortality was 25.0% (4/16) in patients with tunneled HD catheter infection initially treated with antibiotics alone and 2.8% (2/71) in those treated with catheter removal plus antibiotics at the time of presentation (P = 0.0096). Conclusion: Hypoalbuminemia is associated with increased risk of HD access infection. Treatment of HD access infection with antibiotics alone is associated with increased risk of death.     

Obesity promotes forearm primary arteriovenous fistula creation in chronic haemodialyzed patients

The increase in number of obese people seen in the general population, is also what is seen in the hemodialyzed population. It is generally believed that the location of deep forearm vessels in the subcutaneous fat tissue makes primary arteriovenous fistula (AVF) a disadvantage because of difficulties in vessel puncturing. For obese patients, it is suggested that a fistula with PTFE is created or a central catheter inserted, but these solutions increase already high morbidity rate and significantly increase mortality rate. Methods: The deep location of veins situated on the anterior part of the forearm involved 57 patients (45 female and 12 male) aged 13–87 years (mean 67 ± 15.2 years). Patients’ body mass index (BMI) ranged from 29.1 to 53.73 (mean 34.6 ± 7.8). The causes of the renal failure were diabetic nephropathy in 30 patients, chronic glomerulonephritis in 4, hypertensive nephrosclerosis in 5, lupus nephritis in 2, interstitial nephritis in 4, primary amyloidosis in 1, polycystic kidney disease in 3, and unknown in 3 patients.Two‐step surgical procedure was performed in all patients. In the first stage, the standard distal radiocephalic AVF in the wrist region was created. In case of its failure, the next attempt was performed above the point of the first intervention. In the second stage, superficialization of the venous part of AVF was performed in the mode described by us (Kidney 2002;.1:1170). Results: The first stage of the procedure was successful in 46 patients. In 6 cases it was necessary to perform a second attempt, and 2 cases required three operations. The second stage was undertaken in all of these patients (n = 54), and complete success was achieved in 51. In 3 cases, in spite of superficialization, AVF was not suitable for puncturing because of poor blood flow. The causes of failure of the first stage procedure in 2 patients were severe arteriosclerosis and venous anomaly. All patients had non‐altered cephalic veins in the wrist region, as opposed to patients with cannulated veins. In 51 pts (90%) an efficient flow of the blood through AVF was successfully obtained and allowed satisfactory dialyses. Conclusions: The primary AVF creation on the forearm is feasible in 90% of obese patients. This result is similar to the general population of chronic renal disease patients of our center (95%)(NDT 1998;13:527) and is possible thanks to the location of the veins deep in the subcutaneous fat tissue, which protects against repeated cannulation and hence mechanical destruction in the pre‐dialysis period.     

Vascular imaging for hemodialysis vascular access planning

Introduction: Central venous catheters (CVC) increase risks associated with hemodialysis (HD), but may be necessary until an arteriovenous fistula (AVF) or graft (AVG) is achieved. The impact of vascular imaging on achievement of working AVF and AVG has not been firmly established. Methods: Retrospective cohort of patients initiating HD with CVC in 2010–2011, classified by exposure to venography or Doppler vein mapping, and followed through December 31, 2012. Standard and time‐dependent Cox models were used to determine hazard ratios (HRs) of death, working AVF, and any AVF or AVG. Logistic regression was used to assess the association of preoperative imaging with successful AVF or AVG among 18,883 individuals who had surgery. Models were adjusted for clinical and demographic factors. Findings: Among 33,918 patients followed for a median of 404 days, 39.1% had imaging and 55.7% had surgery. Working AVF or AVG were achieved in 40.6%; 46.2% died. Compared to nonimaged patients, imaged patients were more likely to achieve working AVF (HR = 1.45 [95% confidence interval [CI] 1.36, 1.55], P < 0.001]), any AVF or AVG (HR = 1.63 [1.58, 1.69], P > 0.001), and less likely to die (HR = 0.88 [0.83‐0.94], P < 0.001). Among patients who had surgery, the odds ratio for any successful AVF or AVG was 1.09 (1.02–1.16, P = 0.008). Discussion: Fewer than half of patients who initiated HD with a CVC had vascular imaging. Imaged patients were more likely to have vascular surgery and had increased achievement of working AV fistulas and grafts. Outcomes of surgery were similar in patients who did and did not have imaging.     

Clinical effects of buttonhole cannulation method on hemodialysis patients

Although the buttonhole cannulation method is now widely used as an alternative to the rope‐ladder method in most countries, only the latter method is used in Korea. This study was performed to investigate clinical benefit of the buttonhole technique for arteriovenous fistula (AVF) cannulation in maintenance hemodialysis (HD) patients. Thirty‐two patients receiving HD via mature AVF were included and AVF cannulation was performed by 20 experienced nurses. During the 8 weeks, AVFs were cannulated by the rope‐ladder method with 15‐gauge sharp needles. After creating of 2 pairs of tunnel tracks by sharp needles for 7 weeks, AVFs were cannulated by the buttonhole method using 15‐gauge blunt needles during the 16 weeks. Vascular access blood flow rate (BFR), dialysis venous pressure (DVP), and dialysis adequacy (Kt/V) were measured within the first week of the two cannulation methods. Cannulation pain, hemostasis time, and nurse's stress were evaluated at the end of the two methods. There were no statistical differences in vascular access BFR (P = 0.139), DVP (P = 0.152), and dialysis adequacy (P = 0.343) between the two methods. However, the buttonhole method shortened hemostasis time (P = 0.001) and decreased cannulation pain (P = 0.001) as well as nurse's stress (P = 0.001) compared with the rope‐ladder method. In conclusion, the buttonhole cannulation method improves hemostasis time, cannulation pain, and nurse's stress without a change in vascular access BFR and dialysis adequacy in HD patients.