Pain after Arteriovenous Access Creation.

OBJECTIVES: Dialysis access creation is a common outpatient procedure that can be completed using general, regional, or local anesthetic techniques. There are few endorsed guidelines regarding opioid-based pain control following fistula creation. The purpose of this study was to determine whether utilization of regional anesthesia (RA) is associated with the decreased use of narcotics postoperatively. METHODS: We performed a prospective cohort study including all patients undergoing arteriovenous fistula creation with one vascular surgeon from August 2019 to February 2020. Patients were selected for regional versus general anesthesia. Selection for anesthesia type was determined by the primary anesthesiologist. Patients selected for RA underwent supraclavicular brachial plexus block with 30 cm3 of 0.5% ropivacaine. Patients were seen in clinic follow-up and completed a questionnaire regarding their postoperative opiate use and pain control. RESULTS: In the study period, 52 patients underwent arteriovenous fistula creation and completed the follow-up questionnaire. Forty patients received RA. Seventy-five percent of patients sent home with a narcotic prescription filled the prescription. There was a significant difference in postoperative opioid use between the two study groups. Patients who received regional block took on average 3.3 pills totaling 16.5 morphine milligram equivalents, whereas patients who received general anesthesia took on average 6.64 pills totaling 33.2 morphine milligram equivalents (P = 0.04). CONCLUSIONS: Morbidity and mortality related to opiate use continues to be a public health issue in the United States. This study demonstrates that regional anesthetic techniques in comparison to general anesthesia can result in a significant decrease in postoperative opiate consumption.

Music Therapy in Dialysis Access Procedures With Moderate Sedation.

BACKGROUND: The aim was to evaluate the effects of music on patients' anxiety and satisfaction after undergoing dialysis access procedures under moderate sedation. METHODS: Patients (n = 30) undergoing moderate sedation for dialysis access procedures were evaluated at a single institution. Each patient filled out a survey preoperatively and postoperatively using the short form State-Trait Anxiety Inventory (STAI-6). Patient-selected music was provided by using a MP3 player with noise canceling headphones. RESULTS: Postoperatively, 77% of patients perceived music intervention as very or extremely helpful in decreasing anxiety during the procedure. Further, 93% of patients were somewhat or very satisfied with their procedure. The average pain rating was 3.1 on a scale of 0-10, in which 70% of patients had no to mild pain and 30% of patients rated moderate to severe pain. In comparison to prior procedures without music, 63% of patients rated better experience with the music intervention, 37% rated a similar experience, and 3.7% rated having a worse experience. Approximately, 93% of patients were willing to repeat procedure with music and would recommend it to other patients. Preoperative anxiety average score was 35.6 ± 13 and was reduced postoperatively to 28.9 ± 12.9 (P = .006). Preoperatively, 23% of patients rated high anxiety and postoperatively only 6.7% of patients rated high anxiety (P = .016). CONCLUSION: Music is an easy, feasible, inexpensive intervention that may reduce patients' anxiety and improve satisfaction during moderate sedation procedures and in the postoperative period.

Medical adjuvant treatment to increase patency of arteriovenous fistulae and grafts.

BACKGROUND: People with end-stage renal disease (ESRD) often require either the formation of an arteriovenous fistula (AVF) or an interposition prosthetic arteriovenous graft (AVG) for haemodialysis. These access sites should ideally have a long life and a low rate of complications (e.g. thrombosis, infection, stenosis, aneurysm formation and distal limb ischaemia). Although some of the complications may be unavoidable, any adjuvant technique or medical treatment aimed at decreasing complications would be welcome. This is the fourth update of the review first published in 2003. OBJECTIVES: To assess the effects of adjuvant drug treatment in people with ESRD on haemodialysis via autologous AVFs or prosthetic interposition AVGs. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and ClinicalTrials.gov trials register to 6 August 2020. SELECTION CRITERIA: Randomised controlled trials of active drug versus placebo in people with ESRD undergoing haemodialysis via an AVF or prosthetic interposition AVG. DATA COLLECTION AND ANALYSIS: For this update, two review authors (IM, MFAK) independently selected trials for inclusion, extracted data, assessed risk of bias and assessed the certainty of the evidence according to GRADE. We resolved disagreements by discussion or consultation with another review author (ADS). The primary outcome was the long-term fistula or graft patency rate. Secondary outcomes included duration of hospital stay; complications such as infection, aneurysm formation, stenosis and distal limb ischaemia; and number of related surgical or radiological interventions. MAIN RESULTS: For this update, one additional study was suitable for inclusion, making a total of 13 trials with 2080 participants. Overall the certainty of the evidence was low or moderate due to short follow-up periods, heterogeneity between trials, small sample sizes, and risk of bias due to incomplete reporting. Medical adjuvant treatments used in the included trials were aspirin, ticlopidine, dipyridamole, dipyridamole plus aspirin, warfarin, fish oil, clopidogrel, sulphinpyrazone and glyceryl trinitrate (GTN) patch.  All included studies reported on graft patency by measuring graft thrombosis. There was insufficient evidence to determine if there was a difference in graft patency in studies comparing aspirin versus placebo (odds ratio (OR) 0.40, 95% confidence interval (CI) 0.07 to 2.25; 3 studies, 175 participants; low-certainty evidence). The meta-analysis for graft patency comparing ticlopidine versus placebo favoured ticlopidine (OR 0.45, 95% CI 0.25 to 0.82; 3 studies, 339 participants; moderate-certainty evidence). There was insufficient evidence to determine if there was a difference in graft patency in studies comparing fish oil versus placebo (OR 0.24, 95% CI 0.03 to 1.95; 2 studies, 220 participants; low-certainty evidence); and studies comparing clopidogrel and placebo (OR 0.40, 95% CI 0.13 to 1.19; 2 studies, 959 participants; moderate-certainty evidence). Similarly, there was insufficient evidence to determine if there was a difference in graft patency comparing the effect of dipyridamole versus placebo (OR 0.46, 95% CI 0.11 to 1.94; 1 study, 42 participants, moderate-certainty evidence) and dipyridamole plus aspirin versus placebo (OR 0.64, CI 0.16 to 2.56; 1 study, 41 participants; moderate-certainty evidence); comparing low-intensity warfarin with placebo (OR 1.76, 95% CI 0.78 to 3.99; 1 study, 107 participants; low-certainty evidence); comparing sulphinpyrazone versus placebo (OR 0.43, 95% CI 0.03 to 5.98; 1 study, 16 participants; low-certainty evidence) and comparing GTN patch and placebo (OR 1.26, 95% CI 0.63 to 2.54; 1 study, 167 participants; moderate-certainty evidence). The single trial evaluating warfarin was terminated early because of major bleeding events in the warfarin group. Only two studies published data on the secondary outcome of related interventions (surgical or radiological); there was insufficient evidence to determine if there was a difference in related interventions between placebo and treatment groups. None of the included studies reported on the duration of hospital stay.  Most studies reported complications ranging from mortality to nausea. However, data on complications were limited and reporting varied between studies. AUTHORS' CONCLUSIONS: The meta-analyses of three studies for ticlopidine (an antiplatelet treatment), which all used the same dose of treatment but with a short follow-up of only one month, suggest ticlopidine may have a beneficial effect as an adjuvant treatment to increase the patency of AVFs and AVGs in the short term. There was insufficient evidence to determine if there was a difference in graft patency between placebo and other treatments such as aspirin, fish oil, clopidogrel, dipyridamole, dipyridamole plus aspirin, warfarin, sulphinpyrazone and GTN patch. The certainty of the evidence was low to moderate due to short follow-up periods, the small number of studies for each comparison, small sample sizes, heterogeneity between trials and risk of bias due to incomplete reporting. Therefore, it appears reasonable to suggest further prospective studies be undertaken to assess the use of these antiplatelet drugs in renal patients with an AVF or AVG.

Device Therapy of Hypertension.

In the past decade, efforts to improve blood pressure control have looked beyond conventional approaches of lifestyle modification and drug therapy to embrace interventional therapies. Based upon animal and human studies clearly demonstrating a key role for the sympathetic nervous system in the etiology of hypertension, the newer technologies that have emerged are predominantly aimed at neuromodulation of peripheral nervous system targets. These include renal denervation, baroreflex activation therapy, endovascular baroreflex amplification therapy, carotid body ablation, and pacemaker-mediated programmable hypertension control. Of these, renal denervation is the most mature, and with a recent series of proof-of-concept trials demonstrating the safety and efficacy of radiofrequency and more recently ultrasound-based renal denervation, this technology is poised to become available as a viable treatment option for hypertension in the foreseeable future. With regard to baroreflex activation therapy, endovascular baroreflex amplification, carotid body ablation, and programmable hypertension control, these are developing technologies for which more human data are required. Importantly, central nervous system control of the circulation remains a poorly understood yet vital component of the hypertension pathway and mandates further investigation. Technology to improve blood pressure control through deep brain stimulation of key cardiovascular control territories is, therefore, of interest. Furthermore, alternative nonsympathomodulatory intervention targeting the hemodynamics of the circulation may also be worth exploring for patients in whom sympathetic drive is less relevant to hypertension perpetuation. Herein, we review the aforementioned technologies with an emphasis on the preclinical data that underpin their rationale and the human evidence that supports their use.

Comparison of regional and local anesthesia for arteriovenous fistula creation in end-stage renal disease: a systematic review and meta-analysis.

BACKGROUND: Arteriovenous fistulae (AVF) are the hemodialysis access modality of choice for patients with end-stage renal disease. However, they have a high early failure rate. Good vascular access is essential to manage long-term hemodialytic treatment, but some anesthesia techniques directly affect venous diameter as well as intra- and post-operative blood flow. The main purpose of this meta-analysis was to compare the results of regional and local anesthesia (RA and LA) for arteriovenous fistula creation in end-stage renal disease. METHODS: We conducted a systematic review and meta-analysis to synthesize evidence from 7 randomized controlled trials (565 patients) and 1 observational study (408 patients) with the aim of evaluating the safety and efficacy of RA versus LA in surgical construction of AVF. RESULTS: Pooled data showed that RA was associated with higher primary patency rates than LA (odds ratio [OR], 1.88; 95% confidence interval [CI]: 1.24-2.84; P = 0.003; I2 = 31%). Additionally, brachial artery diameter was significantly increased in the RA versus LA group (mean difference [MD], 0.83; 95% CI: 0.75-0.92; P < 0.001; I2 = 97%) and the need for intra- as well as post-operative pain killers was significantly less (RA, P = 0.0363; LA, P = 0.0318). Moreover, operation duration was significantly reduced using RA versus LA (MD, - 29.63; 95% CI: - 32.78 - -26.48; P < 0.001; I2 = 100%). CONCLUSIONS: This meta-analysis suggests that RA is preferable to LA in patients with end-stage renal disease in guaranteeing AVF patency and increasing brachial artery diameter.

Management Strategies for Pain Associated with Arteriovenous Fistula Cannulation: An Integrative Literature Review.

Patients on maintenance hemodialysis are subjected to mild-to-moderate pain associated with arteriovenous fistula needle insertion. This pain might adversely affect patient compliance with dialysis and quality of life. The aim of this study was to evaluate published research studies on management strategies for pain associated with fistula needle insertion. A review of 35 studies from well-known databases such as CINAHL, ProQuest, and PubMed was conducted. Three strategies of cannulation pain management were found to have been tried: specific cannulation techniques; use of alternative complementary therapies; and use of local anesthetic agents.

Should a fistula first policy be revisited in elderly haemodialysis patients?

Life-sustaining haemodialysis requires a durable vascular access (VA) to the circulatory system. The ideal permanent VA must provide longevity for use with minimal complication rate and supply sufficient blood flow to deliver the prescribed dialysis dosage. Arteriovenous fistulas (AVFs) have been endorsed by many professional societies as the VA of choice. However, the high prevalence of comorbidities, particularly diabetes mellitus, peripheral vascular disease and arterial hypertension in elderly people, usually make VA creation more difficult in the elderly. Many of these patients may have an insufficient vasculature for AVF maturation. Furthermore, many AVFs created prior to the initiation of haemodialysis may never be used due to the competing risk of death before dialysis is required. As such, an arteriovenous graft and, in some cases, a central venous catheter, become a valid alternative form of VA. Consequently, there are multiple decision points that require careful reflection before an AVF is placed in the elderly. The traditional metrics of access patency, failure and infection are now being seen in a broader context that includes procedure burden, quality of life, patient preferences, morbidity, mortality and cost. This article of the European Dialysis (EUDIAL) Working Group of ERA-EDTA critically reviews the current evidence on VA in elderly haemodialysis patients and concludes that a pragmatic patient-centred approach is mandatory, thus considering the possibility that the AVF first approach should not be an absolute.

Vascular access surgery can be safely performed in an ambulatory setting.

INTRODUCTION:: Ambulatory surgery is associated with lower costs, but there is lack of evidence of the safety for ambulatory vascular access surgery. The objective of this study is to substantiate the safety and effectiveness of performing vascular access surgery in an ambulatory setting. METHODS:: A review of our prospectively maintained database including all vascular access open surgeries (creations and repairs) performed by our Vascular Access Unit between 2013 and 2017 was compiled. Patient comorbidities, surgery details, hospital admission conditions, and 1-week and 1-month follow-up patency and complications (death, infection, bleeding, and readmission/reintervention) were scrutinized. RESULTS:: In the last 5 years, 1414 vascular access procedures were performed (67.8% access creations, 32.2% previous access repairs) in 1012 patients. Most surgeries were performed under local anesthesia (59.2%) or axillary plexus block (38.4%) and mainly in an ambulatory setting, without overnight hospital stays (90.9%). During the first postoperative week follow-up, 9 cases (0.6%) needed readmission or reintervention; significant infection materialized in 11 (0.8%) and 10 cases (0.7%) showed noteworthy hematoma or bleeding, only three (0.2%) requiring reintervention. The primary composite endpoint of 24-h death and 1 week readmission, reintervention, infection, or bleeding was 1.9% (27 cases); 1-month access failure was 6.2%. After univariate analysis, ambulatory settings were not related to higher rates of complications or readmissions. CONCLUSION:: Arteriovenous access surgery can be safely performed in an ambulatory setting, in spite of complex cases, comorbidities, or the increasing implementation of axillary plexus blocks. Surgical results and patency are good, and complications necessitating readmission remain very low.

Omega-3 fatty acids for dialysis vascular access outcomes in patients with chronic kidney disease.

BACKGROUND: Maintaining long-term vascular access patency is necessary for high quality haemodialysis (HD) treatment of patients with the terminal and most serious stage of chronic kidney disease (CKD) - end-stage kidney disease (ESKD). Oral supplementation with omega-3 fatty acids (ω-3FA) may help to prevent blockage of the vascular access by reducing the risk of thrombosis and stenosis. OBJECTIVES: To evaluate the efficacy and safety of ω-3FA supplementation versus placebo or no treatment for maintaining vascular access patency in ESKD patients undergoing HD. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 23 July 2018 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal, and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials (RCTs) of omega-3 fatty acids versus placebo that assessed the patency of arteriovenous fistula (AVF) or arteriovenous graft (AVG) types of vascular access in ESKD patients. DATA COLLECTION AND ANALYSIS: We assessed the risk of bias of each eligible study using the Cochrane Risk of Bias tool and made separate overall risk of bias judgments for the efficacy and safety outcomes. The certainty of evidence was assessed using the GRADE approach. The primary efficacy outcome was loss of vascular patency and the primary safety outcomes were occurrences of serious adverse events (e.g. death, hospitalisation, cardiovascular events, major bleeding). Secondary outcomes were the occurrence of non-serious adverse events (e.g. minor bleeding, gastrointestinal events and other adverse events). Efficacy effects were reported as risk ratios (RR) and safety effects as risk differences (RD) with 95% confidence intervals (CI). Studies were pooled separately by type of vascular access using a random-effects model. MAIN RESULTS: Five studies (833 participants) were included; one was a very small pilot study of 7 participants. All studies compared oral ω-3FA supplements against placebo. Four studies enrolled participants with arteriovenous grafts (AVGs), and the other had participants with arteriovenous fistulas (AVFs). The risk of bias for both efficacy and safety outcomes was unclear for all studies, due mainly to incomplete reporting for allocation concealment and incompleteness of study follow-up.In AVF patients, ω-3FA supplementation probably makes little or no difference to the 12-month risk of patency loss (1 study, 536 participants: RR 1.01, 95% CI 0.84 to 1.21; moderate certainty evidence), risk of death (1 study, 567 participants: RD 0.00, 95% CI -0.03 to 0.02; moderate certainty evidence) and risk of hospitalisation (1 study, 567 participants: RD 0.00, 95% CI -0.08 to 0.08; low certainty evidence). There was no information on cardiovascular events and major bleeding.In AVG patients, it is very uncertain whether ω-3FA supplementation reduces the risk of patency loss within 6 months (2 studies, 41 participants: RR 0.91, 95% CI 0.36 to 2.28; very low certainty evidence) or 12 months (2 studies, 220 participants: RR 0.59, 95% CI 0.27 to 1.31; very low certainty evidence). ω-3FA supplementation may make little or no difference to the risk of death within 6 to 12 months in AVG patients (4 studies, 261 participants: RD 0.01, 95% CI -0.05 to 0.07; low certainty evidence). It is very uncertain if ω-3FA supplementation increases the risk of hospitalisation (3 studies, 65 participants: RD 0.08, 95% CI -0.11 to 0.28; very low certainty evidence), changes the risk of cardiovascular events (4 studies, 261 participants: RD -0.02, 95% CI -0.11 to 0.07; very low certainty evidence), or increases the risk of major bleeding (3 studies, 65 participants: RD 0.08, 95% CI -0.11 to 0.28; very low certainty evidence) within 6 to 12 months in AVG patients. There may be an increase in the risk of mild gastrointestinal adverse reactions (3 studies, 65 participants: RD 0.25, 95% CI 0.07 to 0.43; low certainty evidence) such as a sensation of bloatedness, gas or a fishy aftertaste. AUTHORS' CONCLUSIONS: In CKD patients with an AVF, there is moderate certainty that ω-3FA supplementation makes little or no difference to preventing patency loss; and in patients with an AVG, it is very uncertain that ω-3FA supplementation prevents patency loss within 12 months.

Regional versus local anesthesia for arteriovenous fistula creation in end-stage renal disease: a systematic review and meta-analysis.

There is a consensus in the literature that regional anesthesia (RA) improves local hemodynamic parameters in comparison to local anesthesia (LA) during arteriovenous fistula (AVF) surgical construction. However, the effects of both techniques on fistula patency and failure rates are still controversial. The aim of this meta-analysis is to synthesize evidence from published randomized trials and observational studies regarding the safety and efficacy of RA versus LA in AVF surgical construction. A computer literature search of PubMed, Scopus, Web of Science, and Cochrane Central retrieved six randomized trials (462 patients) and one retrospective study (408 patients). Pooling data using RevMan software (version 5.3) showed that RA was superior to LA in terms of primary fistula patency rate (RR = 1.22, 95% CI [1.08, 1.37], p = 0.0010); however, both types were comparable in terms of primary fistula failure rate (RR = 0.81, 95% CI [0.47, 1.40], p = 0.46). In comparison to LA, RA was associated with improved hemodynamic parameters including fistula blood flow (MD = 25.08, 95% CI [19.40, 30.76], p<0.00001), brachial artery diameter (SMD = 2.63, 95% CI [2.17, 3.08], p<0.00001), and outflow venous diameter (SMD = 0.93, 95% CI [0.30, 1.75], p = 0.004). Postoperative complications were comparable between both groups (OR = 0.23, 95% CI [0.05, 0.97], p = 0.05). In conclusion, RA was associated with higher primary patency rates of AVF and improved local blood flow in comparison to LA; however, both procedures were comparable in terms of primary failure rates and postoperative complications. Larger well-designed trials with longer follow-up periods should compare both techniques in terms of long-term patency rates and safety outcomes.

Regional Versus Local Anaesthesia for Haemodialysis Arteriovenous Fistula Formation: A Systematic Review and Meta-Analysis.

BACKGROUND: Arteriovenous fistula (AVF) formation is the most common vascular access procedure for patients requiring haemodialysis. However, it is associated with high failure rates, influenced by vessel diameter and arterial inflow. Mode of anaesthesia may affect these factors, and subsequently AVF maturation rates. OBJECTIVE: To perform a systematic review and meta-analysis to assess the effect of anaesthesia type for autologous primary radiocephalic or brachiocephalic AVF creation on subsequent fistula failure rates. METHODS: The online databases of Medline, EMBASE, CINAHL, The Cochrane Database of Systematic Reviews, ClinicalTrials.gov, and Google Scholar as well as vascular and anaesthesiology conference abstracts were searched on August 1, 2016. Randomised control trials (RCTs) that reported the effect of anaesthesia type on subsequent failure rates during autologous AVF creation were included. Two independent reviewers performed methodological assessment and data extraction. Random effects models were used to calculate pooled effect size estimates. A sensitivity analysis was also carried out. RESULTS: Four RCTs (286 patients) were identified with 286 autologous AVFs. There were 48 fistula failures. Most of the studies suffered from significant methodological flaws. There was a significantly lower failure rate among patients undergoing regional (12/143) compared with local (36/143) anaesthesia (OR 0.28, 95% CI 0.14-0.57). On sensitivity analysis, having excluded the most heavily weighted study, the results remained significant (OR 0.20, 95% CI 0.05-0.75). CONCLUSIONS: The use of regional anaesthesia is associated with lower AVF failure rates when compared with local anaesthesia in patients undergoing primary forearm AVF formation for haemodialysis.

General, regional or local anesthesia for successful radial cephalic arteriovenous fistula.

Autogenous fistulas and in particular radiocephalic fistulas are recommended as the first vascular access for hemodialysis. Unfortunately, the rates of early failure and non-maturation are very high. For more than a decade, brachial plexus block has been proposed as the anesthesia of choice for fistula creation due to its beneficial sympathectomy-like effect, causing vasodilation and attenuation of spasm. Until recently, there was not a single randomized clinical study supporting this proposition. Because performing regional anesthesia is time-consuming and requires expertise, many surgeons prefer local or general anesthesia for vascular access surgery. However, in August 2016 a randomized clinical trial was published showing that regional anesthesia significantly reduces early failure and improves primary and functional patency at 3 months compared to local anesthesia. The aging of the dialysis population, with their attendant morbidity and increased risk for general anesthesia, makes it clear that regional anesthesia is the recommended approach for fistula creation. The excess time required for this approach will decrease with increasing expertise along the learning curve, and will be compensated by a reduction in time that would otherwise be needed for new access construction due to failure of fistulas constructed under local anesthesia.

Interventional procedures and future drug therapy for hypertension.

Hypertension management poses a major challenge to clinicians globally once non-drug (lifestyle) measures have failed to control blood pressure (BP). Although drug treatment strategies to lower BP are well described, poor control rates of hypertension, even in the first world, suggest that more needs to be done to surmount the problem. A major issue is non-adherence to antihypertensive drugs, which is caused in part by drug intolerance due to side effects. More effective antihypertensive drugs are therefore required which have excellent tolerability and safety profiles in addition to being efficacious. For those patients who either do not tolerate or wish to take medication for hypertension or in whom BP control is not attained despite multiple antihypertensives, a novel class of interventional procedures to manage hypertension has emerged. While most of these target various aspects of the sympathetic nervous system regulation of BP, an additional procedure is now available, which addresses mechanical aspects of the circulation. Most of these new devices are supported by early and encouraging evidence for both safety and efficacy, although it is clear that more rigorous randomized controlled trial data will be essential before any of the technologies can be adopted as a standard of care.

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

BACKGROUND: Native 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. METHODS: In 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. RESULTS: In 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). CONCLUSIONS: VLPD 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.

Medical Adjuvant Treatment to Improve the Patency of Arteriovenous Fistulae and Grafts: A Systematic Review and Meta-analysis.

BACKGROUND: Many patients using haemodialysis for end-stage renal disease (ESRD) require arteriovenous fistulae (AVF) or grafts. Patency can be variable, and this systematic review aimed to determine the effects of adjuvant drug treatment on the patency of AVFs and grafts. METHODS: The Cochrane Peripheral Vascular Diseases Group searched the Specialised Register and CENTRAL for all randomised controlled trials (RCTs) investigating the effect of active drug versus placebo on patency. The primary outcome was fistula or graft patency rate. The odds ratio (OR) was used as the measure of effect for each outcome. If several trials assessed the same adjuvant therapy then a meta-analysis was conducted using a Mantel-Haenszel model. RESULTS: Fifteen trials were deemed suitable for inclusion, investigating nine drug treatments in 2,230 participants. Overall, the quality of evidence was low. Three trials compared ticlopidine (a platelet aggregation inhibitor) versus placebo and favoured active treatment (OR 0.45, 95% CI 0.25 to 0.82; p = .009). Three RCTs assessed aspirin versus placebo and did not show a statistical benefit (OR 0.40, 95% CI 0.07-2.25; p = .30). Two trials compared clopidogrel with placebo. The overall result did not favour treatment (OR 0.40, 95% CI 0.13 to 1.19; p = .10). Three trials evaluated human type-I pancreatic elastase but did not provide evidence of improved patency (OR 0.75, 95% CI 0.42-1.32; p = .31). Finally, two RCTs assessed fish oil and did not favour treatment (OR 0.24, 95% CI 0.03-1.95; p = .18). Single trials comparing dipyridamole alone, dipyridamole plus aspirin, and sulfinpyrazone against placebo favoured active treatment but a meta-analysis could not be undertaken. Finally, a single trial of warfarin versus placebo found warfarin resulted in increased complications and worse patency rates. CONCLUSION: This systematic review has not demonstrated a beneficial effect for any adjuvant treatment to increase the patency of AVF or grafts in the short term, except ticlopidine which has been taken off the market.

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

BACKGROUND: 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, laryngeal mask airway, regional anesthesia with nerve blocks, and monitored anesthesia care with local infiltration. It is unclear what effect the method of anesthesia has on AVF creation success rate. It is our objective to determine if anesthesia type affects success of these surgeries defined by complication and maturation rates. METHODS: 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 3 anesthesia types (General Endotracheal Intubation, Laryngeal Mask Airway and Local Infiltration with Monitored Anesthesia Care) and AVF creation surgeries (radiocephalic, brachiocephalic, and basilic vein transposition). No patients had regional anesthesia performed. Demographic data including comorbidities and risk factors were stratified among all categories. Analysis of variance, chi-squared testing, and Fisher's exact P testing was performed across all anesthesia types and specific operations and measured according to success of fistula 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). RESULTS: There were no significant differences in maturation rate in terms of all 3 anesthesia types for radiocephalic (P = 0.191), brachiocephalic (P = 0.191), and basilic vein transposition surgeries (P = 0.305). In addition, there were no differences in complication rates between the surgeries and the 3 types of anesthesia (P = 0.557). CONCLUSIONS: 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 in terms of time in the operating room and in the recovery unit and therefore may be the preferred method of anesthesia. This recommendation may also parallel the preference to avoid general anesthesia in a patient population with more medical comorbidities. It is our conclusion that dialysis access surgery should therefore be performed under local anesthesia with monitored anesthesia care.

Medical adjuvant treatment to increase patency of arteriovenous fistulae and grafts.

BACKGROUND: End-stage renal disease (ESRD) patients often require either the formation of an arteriovenous (AV) fistula or an AV interposition prosthetic shunt for haemodialysis. These access sites should ideally have a long life and a low rate of complications (for example thrombosis, infection, stenosis, aneurysm formation and distal limb ischaemia). Although some of the complications may be unavoidable, any adjuvant technique or medical treatment aimed at decreasing complications would be welcome. This is the second update of the review first published in 2004. OBJECTIVES: To assess the effects of adjuvant drug treatment in ESRD patients on haemodialysis via autologous AV fistulae or prosthetic interposition AV shunts. SEARCH METHODS: For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2015) and CENTRAL (2015, Issue 2). SELECTION CRITERIA: Randomised controlled trials (RCTs) of active drug versus placebo in people with ESRD undergoing haemodialysis via an AV fistula or prosthetic interposition AV graft. DATA COLLECTION AND ANALYSIS: For this update, the two review authors (NCT, ADS) independently assessed trial quality and one review author (NCT) extracted data. Information on adverse events was collected from the trials. The primary outcome was the long-term fistula or graft patency rate. Secondary outcomes included duration of hospital stay, complications and number of related surgical interventions. MAIN RESULTS: For this update, an additional six studies were deemed suitable for inclusion, making a total of 15 trials with 2230 participants. Overall the quality of the evidence was low due to short follow-up periods, heterogeneity between trials and moderate methodological quality of the studies due to incomplete reporting. Medical adjuvant treatments used in the trials were aspirin, ticlopidine, dipyridamole, dipyridamole plus aspirin, warfarin, fish oil, clopidogrel, sulphinpyrazone, and human type I pancreatic elastase (PRT-201). Where possible, the included studies were pooled into similar medical adjuvant groups for meta-analyses.All included studies reported on graft patency by measuring graft thrombosis. There was insufficient evidence to determine if there was a difference in graft patency in studies comparing aspirin versus placebo (three RCTs, 175 participants) (odds ratio (OR) 0.40, 95% confidence interval (CI) 0.07 to 2.25; P = 0.30). The meta-analysis for graft patency comparing ticlopidine versus placebo (three RCTs, 339 participants) favoured ticlopidine (OR 0.45, 95% CI 0.25 to 0.82; P = 0.009). There was insufficient evidence to determine if there was a difference in graft patency in studies comparing fish oil versus placebo (two RCTs, 220 participants; OR 0.24, 95% CI 0.03 to 1.95; P = 0.18); and studies comparing clopidogrel and placebo (two RCTs, 959 participants; OR 0.40, 95% CI 0.13 to 1.19; P = 0.10). Similarly, there was insufficient evidence to determine if there was a difference in graft patency in three studies (306 participants) comparing PRT-201 versus placebo (OR 0.75, 95% CI 0.42 to 1.32; P = 0.31); in one trial comparing the effect of dipyridamole versus placebo (42 participants; OR 0.46, 95% CI 0.11 to 1.94, P = 0.29) and dipyridamole plus aspirin versus placebo (41 participants; OR 0.64, CI 0.16 to 2.56, P = 0.52); in one trial comparing low-dose warfarin with placebo (107 participants; OR 1.76, 95% CI 0.78 to 3.99, P = 0.17); and one trial (16 participants) comparing sulphinpyrazone versus placebo (OR 0.43, 95% CI 0.03 to 5.98, P = 0.53). The single trial evaluating warfarin was terminated early because of major bleeding events in the warfarin group. Only two studies published data on the secondary outcome of related interventions (surgical or radiological); there was insufficient evidence to determine if there was a difference in related interventions between placebo and treatment groups. No studies reported on the length of hospital stay and data reporting on complications was limited and varied between studies. AUTHORS' CONCLUSIONS: The meta-analyses of three studies for ticlopidine (an anti-platelet treatment), which all used the same dose of treatment but with a short follow-up of only one month, suggest ticlopidine may have a beneficial effect as an adjuvant treatment to increase the patency of AV fistulae and grafts in the short term. There was insufficient evidence to determine if there was a difference in graft patency between placebo and other treatments such as aspirin, fish oil, clopidogrel, PRT-201, dipyridamole, dipyridamole plus aspirin, warfarin, and sulphinpyrazone. However, the quality of the evidence was low due to short follow-up periods, the small number of studies for each comparison, heterogeneity between trials and moderate methodological quality of the studies due to incomplete reporting. It, therefore, appears reasonable to suggest further prospective studies be undertaken to assess the use of these anti-platelet drugs in renal patients with an arteriovenous fistula or graft.

The Omega-3 fatty acids (Fish Oils) and Aspirin in Vascular access OUtcomes in REnal Disease (FAVOURED) study: the updated final trial protocol and rationale of post-initiation trial modifications.

BACKGROUND: The FAVOURED study is an international multicentre, double-blind, placebo-controlled trial which commenced recruitment in 2008 and examines whether omega-3 polyunsaturated fatty acids (omega-3 PUFAs) either alone or in combination with aspirin will effectively reduce primary access failure of de novo arteriovenous fistulae (AVF) in patients with stage 4 and 5 chronic kidney disease. Publication of new evidence derived from additional studies of clopidogrel and a high screen failure rate due to prevalent aspirin usage prompted an updated trial design. METHODS/DESIGN: The original trial protocol published in 2009 has undergone two major amendments, which were implemented in 2011. Firstly, the primary outcome 'early thrombosis' at 3 months following AVF creation was broadened to a more clinically relevant outcome of 'AVF access failure'; a composite of thrombosis, AVF abandonment and cannulation failure at 12 months. Secondly, participants unable to cease using aspirin were allowed to be enrolled and randomised to omega-3 PUFAs or placebo. The revised primary aim of the FAVOURED study is to test the hypothesis that omega-3 PUFAs will reduce rates of AVF access failure within 12 months following AVF surgery. The secondary aims are to examine the effect of omega-3 PUFAs and aspirin on the individual components of the primary end-point, to examine the safety of study interventions and assess central venous catheter requirement as a result of access failure. DISCUSSION: This multicentre international clinical trial was amended to address the clinically relevant question of whether the usability of de novo AVF at 12 months can be improved by the early use of omega-3 PUFAs and to a lesser extent aspirin. This study protocol amendment was made in response to a large trial demonstrating that clopidogrel is effective in safely preventing primary AVF thrombosis, but ineffective at increasing functional patency. Secondly, including patients taking aspirin will enroll a more representative cohort of haemodialysis patients, who are significantly older with a higher prevalence of cardiovascular disease and diabetes which may increase event rates and the power of the study. TRIAL REGISTRATION: Australia & New Zealand Clinical Trial Register (ACTRN12607000569404).

How to perform safe anesthesia in patients with end-stage renal disease.

Vascular surgical patients and especially those with end-stage renal disease are exposed to a high risk of preventable adverse events. Typically, a combination of organizational and technical deficiencies, human error or ineptitude and patient comorbidity leads to inadvertently poor outcome. Patient safety in perioperative environments requires permanent effort in organizational improvement, staff training, and maintenance of high standards in patient care and technical equipment. Even in multimorbid patients, anesthesia for vascular access surgery can be performed at low to moderate risk if safety problems are minimized.

Staple aneurysmorrhaphy to salvage autogenous arteriovenous fistulas with aneurysm-related complications.

OBJECTIVE: Aneurysm-related complications could lead to loss of a functioning arteriovenous fistula (AVF). We report our midterm and long-term results with the staple aneurysmorrhaphy technique to repair and preserve aneurysmal AVFs. METHODS: We retrospectively reviewed our surgical treatment of patients with aneurysmal autogenous AVF complicated by skin erosion, bleeding, infection, pain, and difficulty with needle access from 2007 through 2014. We identified 52 patients, 40 (77%) of whom underwent repair with the staple aneurysmorrhaphy technique. The operation involved mobilizing the entire aneurysmal segments. A TA (Covidien, Norwalk, Conn) or Endo GIA (Covidien, Mansfield, Mass) stapler was used to resect the redundant aneurysm wall to create a 6- to 8-mm-diameter conduit. A subcutaneous skin flap was created after excising compromised skin. The remodeled vein was repositioned underneath the subcutaneous flap, with the staple line rotated laterally to avoid needle puncture. RESULTS: We attempted staple aneurysmorrhaphy in 40 patients with complicated AVF aneurysms, of which 38 repairs (95%) were successful. Median patient age was 66 years (range, 29-88 years). Median AVF age was 63 months (range, 12-136 months). Median follow-up was 20 months (range, 5-81 months). At 1 year, primary patency was 67%, assisted primary patency was 88%, and secondary patency was 91%. At 2 years, primary patency was 59%, assisted primary patency was 84%, and secondary patency was 91%. At 3 years, primary patency was 46%, assisted primary patency was 69%, and secondary patency was 85%. Surgery was performed under local-regional anesthesia in 28 patients (70%) and under general anesthesia in the remaining 12 (30%). Proximal venous outflow stenoses were detected in 19 of 40 AVFs (48%) preoperatively and in 11 of 38 AVFs (29%) postoperatively. Aneurysm recurrence occurred in two repaired AVFs. CONCLUSIONS: Our experience with staple aneurysmorrhaphy shows that it is an effective, safe, and durable procedure to preserve a functioning autogenous AVF with complicated aneurysmal degeneration. Key principles are to reduce the vein to normal adjacent diameter and to provide healthy skin coverage. The remodeled AVF has a low aneurysm recurrence rate and maintains the beneficial properties of superior patency and low infection. It is important to aggressively monitor for and treat proximal outflow venous stenoses to prevent aneurysm recurrence. The surgery can be done safely under local anesthesia in selected patients.