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Nephrology, Dialysis, Transplantation :... Sep 2023There is great potential to improve outcomes of arteriovenous fistulas (AVFs) by focusing more on the preoperative period of AVF creation. We aim to systematically... (Meta-Analysis)
Meta-Analysis
BACKGROUND
There is great potential to improve outcomes of arteriovenous fistulas (AVFs) by focusing more on the preoperative period of AVF creation. We aim to systematically review the evidence on safety and efficacy of various preoperative interventions that have been tried to improve AVF maturation and success rate.
METHODS
We searched five databases: PubMed, Embase, CINAHL, Cochrane Library and King's Fund Library. Experimental studies that investigated the effect of various preoperative interventions to improve AVF outcomes among advanced chronic kidney disease (CKD) patients were searched. The effect size for primary outcome was calculated as the weighted mean difference in the final vessel calibre, rate of AVF maturation or primary failure between the intervention and control arm. We also assessed adverse effects and dropout rates. This review was preregistered in the International Prospective Register of Systematic Reviews (CRD42020193257).
RESULTS
Eight eligible studies were identified involving three types of intervention: hand exercise (n = 6), cholecalciferol supplementation (n = 1) and pneumatic compression of the arm using a Fist Assist device (n = 1). The overall effect size of hand exercise on distal cephalic vein calibre was 0.24 mm [95% confidence interval (CI) 0.03-0.45] on meta-analysis of hand exercise studies. On restricting analysis to two randomized controlled trials (RCTs) that had independent control groups, the effect size was higher, at 0.29 mm (95% CI 0.11-0.47). Hand exercise was a well-tolerated intervention, especially when confined to the first 4 weeks.
DISCUSSION
Hand exercise is the predominant intervention tried in the preoperative period of AVF creation, although there is methodological heterogeneity. Intermittent pneumatic compression using a Fist Assist device is a novel intervention that has shown some promise. Well-designed prospective RCTs are needed on preoperative interventions among advanced CKD patients, aimed at improving AVF outcomes.
Topics: Humans; Arteriovenous Shunt, Surgical; Renal Dialysis; Renal Insufficiency, Chronic; Exercise Therapy; Arteriovenous Fistula
PubMed: 36805738
DOI: 10.1093/ndt/gfad040 -
The Journal of Vascular Access Mar 2024Introducing new procedures and challenging established paradigms requires well-designed randomised controlled trials (RCT). However, RCT in surgery present unique... (Review)
Review
BACKGROUND
Introducing new procedures and challenging established paradigms requires well-designed randomised controlled trials (RCT). However, RCT in surgery present unique challenges with much of treatment tailored to the individual patient circumstances, refined by experience and limited by organisational factors. There has been considerable debate over the outcomes of arteriovenous grafts (AVG) compared to AVF, but any differences may reflect differing practice and potential variability. It is essential, therefore, when considering an RCT of a novel surgical procedure or device that (QA) is defined for both the new approach and the comparator. The aim of this systematic review was to evaluate the QA standards performed in RCT of AVG using a multi-national, multi-disciplinary approach and propose an approach for future RCT.
METHOD
The methods of this have been previously registered (PROSPERO: CRD420234284280) and published. In summary, a four-stage review was performed: identification of RCT of AVG, initial review, multidisciplinary appraisal of QA methods and reconciliation. QA measures were sought in four areas - generic, credentialing, standardisation and monitoring, with data abstracted by a multi-national, multi-speciality review body.
RESULTS
QA in RCT involving AVG in all four domains is highly variable, often sub-optimally described and has not improved over the past three decades. Few RCT established or defined a pre-RCT level of experience, none documented a pre-trial education programme, or had minimal standards of peri-operative management, no study had a defined pre-trial monitoring programme, and none assessed technical performance.
CONCLUSION
QA in RCT is a relatively new area that is expanding to ensure evidence is reliable and reproducible. This review demonstrates that QA has not previously been detailed, but can be measured in surgical RCT of vascular access, and that a four-domain approach can easily be implemented into future RCT.
PubMed: 38501338
DOI: 10.1177/11297298241236521 -
Journal of Vascular Surgery Feb 2024In the United States, an estimated $2.8 billion annually is spent on vascular access and its complications. Endovascular arteriovenous fistula (endoAVF) creation is a...
OBJECTIVE
In the United States, an estimated $2.8 billion annually is spent on vascular access and its complications. Endovascular arteriovenous fistula (endoAVF) creation is a novel, minimally invasive alternative to traditional surgical AV fistula (sAVF) creation in ≤60% of patients. Although cost effective in single-payer systems, the clinical and financial impact of endoAVF in the United States remains uncertain.
METHODS
We constructed a decision tree followed by a probabilistic cohort state-transition model to study the cost effectiveness of endoAVF vs sAVF creation. We conducted a systematic review to obtain input parameters including technical success, maturation, patency, and utility values. We derived costs from the Medicare 2022 fee schedule and from the literature. We used a 5-year time horizon, an annual discount rate of 3% for costs and utilities (measured in quality-adjusted life-years [QALYs]), and the common willingness-to-pay threshold of $50,000. One-way and Monte Carlo probabilistic sensitivity analyses were performed varying technical success, patency, reintervention, cost, and utility parameters.
RESULTS
In the base-case scenario, endoAVF ($30,129 average per-person costs, 2.19 QALYs gained, 65% patent at 5 years) was not cost effective compared with sAVF ($12.987 average per-person costs, 2.11 QALYs gained, 66% patent at 5 years), generating an incremental cost-effectiveness ratio of $227,504 per QALY gained. In one-way sensitivity analyses, endoAVF becomes cost effective when the initial cost of sAVF creation exceeds endoAVF by ≥$600 (eg, if endoAVF creation costs ≤$3000 relative to the base-case sAVF cost of $3600), the additional QALYs gained from endoAVF exceeds 0.12 QALYs/year (eg, 0.81 QALYs gained/year from endoAVF compared with base-case sAVF 0.69 QALYs/year), the endoAVF maturation rate is >90% (base case 78%), or the sAVF maturation rate is <65% (base case 78%). Probabilistic sensitivity analysis demonstrated that sAVF remained the optimal strategy in 71% of iterations.
CONCLUSIONS
EndoAVF is not cost effective compared with sAVF when modeling 5-year outcomes. The main driver of sAVF remaining cost effective is the four times higher up-front cost for endoAVF creation, as well as a relatively low additional increase in quality of life for endoAVF. It will be important to establish how the endoAVF learning curve contributes to upfront costs and, given the annual cost attributed to vascular access nationally, a randomized controlled trial is warranted.
Topics: Humans; Arteriovenous Fistula; Cost-Effectiveness Analysis; Medicare; Quality of Life; Quality-Adjusted Life Years; United States
PubMed: 37952783
DOI: 10.1016/j.jvs.2023.11.009 -
Neurosurgical Focus Mar 2024With recent advancements in minimally invasive techniques, endovascular embolization has gained popularity as a first-line treatment option for spinal dural...
OBJECTIVE
With recent advancements in minimally invasive techniques, endovascular embolization has gained popularity as a first-line treatment option for spinal dural arteriovenous fistulas (sDAVFs). The authors present their institution's case series of sDAVFs treated endovascularly and surgically, and they performed a systemic review to assess the outcomes of both modalities of treatment.
METHODS
The authors conducted a retrospective observational study of 24 consecutive patients with sDAVFs treated between 2013 and 2023. The primary outcome was the rate of occlusion, which was compared between the surgically and endovascularly treated sDAVFs. They also conducted a systemic review of all the literature comparing outcomes of endovascular and surgical treatment of sDAVFs.
RESULTS
A total of 24 patients with 24 sDAVFs were studied. The mean patient age was 63.8 ± 15.5 years, and the majority of patients were male (n = 19, 79.2%). Of the 24 patients, 8 (33.3%) received endovascular treatment, 15 (62.5%) received surgical treatment, and 1 (4.2%) patient received both. Complete occlusion at first follow-up was higher in the surgical cohort but did not achieve statistical significance (66.7% vs 25%, p = 0.52). Recurrence was higher in the endovascular cohort (37.5% vs 13.3%, p = 0.3), while the rate of postprocedural complications was higher in the surgical cohort (13.3% vs 0%, p = 0.52); however, neither of these differences was statistically significant.
CONCLUSIONS
Endovascular embolization in the management of sDAVFs is an alternative treatment to surgery, whose long-term efficacy is still under investigation. These findings suggest overall comparable outcomes between endovascular and open surgical treatment of sDAVFs. Future studies are needed to determine the role of endovascular embolization in the overall management of sDAVFs.
Topics: Humans; Male; Female; Middle Aged; Aged; Treatment Outcome; Neurosurgical Procedures; Endovascular Procedures; Spine; Central Nervous System Vascular Malformations; Observational Studies as Topic
PubMed: 38427989
DOI: 10.3171/2023.12.FOCUS23747 -
The Cochrane Database of Systematic... Jun 2024Peritoneal dialysis (PD) and haemodialysis (HD) are two possible modalities for people with kidney failure commencing dialysis. Only a few randomised controlled trials... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Peritoneal dialysis (PD) and haemodialysis (HD) are two possible modalities for people with kidney failure commencing dialysis. Only a few randomised controlled trials (RCTs) have evaluated PD versus HD. The benefits and harms of the two modalities remain uncertain. This review includes both RCTs and non-randomised studies of interventions (NRSIs).
OBJECTIVES
To evaluate the benefits and harms of PD, compared to HD, in people with kidney failure initiating dialysis.
SEARCH METHODS
We searched the Cochrane Kidney and Transplant Register of Studies from 2000 to June 2024 using search terms relevant to this review. Studies in the Register were identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov. MEDLINE and EMBASE were searched for NRSIs from 2000 until 28 March 2023.
SELECTION CRITERIA
RCTs and NRSIs evaluating PD compared to HD in people initiating dialysis were eligible.
DATA COLLECTION AND ANALYSIS
Two investigators independently assessed if the studies were eligible and then extracted data. Risk of bias was assessed using standard Cochrane methods, and relevant outcomes were extracted for each report. The primary outcome was residual kidney function (RKF). Secondary outcomes included all-cause, cardiovascular and infection-related death, infection, cardiovascular disease, hospitalisation, technique survival, life participation and fatigue.
MAIN RESULTS
A total of 153 reports of 84 studies (2 RCTs, 82 NRSIs) were included. Studies varied widely in design (small single-centre studies to international registry analyses) and in the included populations (broad inclusion criteria versus restricted to more specific participants). Additionally, treatment delivery (e.g. automated versus continuous ambulatory PD, HD with catheter versus arteriovenous fistula or graft, in-centre versus home HD) and duration of follow-up varied widely. The two included RCTs were deemed to be at high risk of bias in terms of blinding participants and personnel and blinding outcome assessment for outcomes pertaining to quality of life. However, most other criteria were assessed as low risk of bias for both studies. Although the risk of bias (Newcastle-Ottawa Scale) was generally low for most NRSIs, studies were at risk of selection bias and residual confounding due to the constraints of the observational study design. In children, there may be little or no difference between HD and PD on all-cause death (6 studies, 5752 participants: RR 0.81, 95% CI 0.62 to 1.07; I = 28%; low certainty) and cardiovascular death (3 studies, 7073 participants: RR 1.23, 95% CI 0.58 to 2.59; I = 29%; low certainty), and was unclear for infection-related death (4 studies, 7451 participants: RR 0.98, 95% CI 0.39 to 2.46; I = 56%; very low certainty). In adults, compared with HD, PD had an uncertain effect on RKF (mL/min/1.73 m) at six months (2 studies, 146 participants: MD 0.90, 95% CI 0.23 to 3.60; I = 82%; very low certainty), 12 months (3 studies, 606 participants: MD 1.21, 95% CI -0.01 to 2.43; I = 81%; very low certainty) and 24 months (3 studies, 334 participants: MD 0.71, 95% CI -0.02 to 1.48; I = 72%; very low certainty). PD had uncertain effects on residual urine volume at 12 months (3 studies, 253 participants: MD 344.10 mL/day, 95% CI 168.70 to 519.49; I = 69%; very low certainty). PD may reduce the risk of RKF loss (3 studies, 2834 participants: RR 0.55, 95% CI 0.44 to 0.68; I = 17%; low certainty). Compared with HD, PD had uncertain effects on all-cause death (42 studies, 700,093 participants: RR 0.87, 95% CI 0.77 to 0.98; I = 99%; very low certainty). In an analysis restricted to RCTs, PD may reduce the risk of all-cause death (2 studies, 1120 participants: RR 0.53, 95% CI 0.32 to 0.86; I = 0%; moderate certainty). PD had uncertain effects on both cardiovascular (21 studies, 68,492 participants: RR 0.96, 95% CI 0.78 to 1.19; I = 92%) and infection-related death (17 studies, 116,333 participants: RR 0.90, 95% CI 0.57 to 1.42; I = 98%) (both very low certainty). Compared with HD, PD had uncertain effects on the number of patients experiencing bacteraemia/bloodstream infection (2 studies, 2582 participants: RR 0.34, 95% CI 0.10 to 1.18; I = 68%) and the number of patients experiencing infection episodes (3 studies, 277 participants: RR 1.23, 95% CI 0.93 to 1.62; I = 20%) (both very low certainty). PD may reduce the number of bacteraemia/bloodstream infection episodes (2 studies, 2637 participants: RR 0.44, 95% CI 0.27 to 0.71; I = 24%; low certainty). Compared with HD; It is uncertain whether PD reduces the risk of acute myocardial infarction (4 studies, 110,850 participants: RR 0.90, 95% CI 0.74 to 1.10; I = 55%), coronary artery disease (3 studies, 5826 participants: RR 0.95, 95% CI 0.46 to 1.97; I = 62%); ischaemic heart disease (2 studies, 58,374 participants: RR 0.86, 95% CI 0.57 to 1.28; I = 95%), congestive heart failure (3 studies, 49,511 participants: RR 1.10, 95% CI 0.54 to 2.21; I = 89%) and stroke (4 studies, 102,542 participants: RR 0.94, 95% CI 0.90 to 0.99; I = 0%) because of low to very low certainty evidence. Compared with HD, PD had uncertain effects on the number of patients experiencing hospitalisation (4 studies, 3282 participants: RR 0.90, 95% CI 0.62 to 1.30; I = 97%) and all-cause hospitalisation events (4 studies, 42,582 participants: RR 1.02, 95% CI 0.81 to 1.29; I = 91%) (very low certainty). None of the included studies reported specifically on life participation or fatigue. However, two studies evaluated employment. Compared with HD, PD had uncertain effects on employment at one year (2 studies, 593 participants: RR 0.83, 95% CI 0.20 to 3.43; I = 97%; very low certainty).
AUTHORS' CONCLUSIONS
The comparative effectiveness of PD and HD on the preservation of RKF, all-cause and cause-specific death risk, the incidence of bacteraemia, other vascular complications (e.g. stroke, cardiovascular events) and patient-reported outcomes (e.g. life participation and fatigue) are uncertain, based on data obtained mostly from NRSIs, as only two RCTs were included.
Topics: Humans; Peritoneal Dialysis; Renal Dialysis; Randomized Controlled Trials as Topic; Bias; Kidney Failure, Chronic; Quality of Life; Adult; Cause of Death; Middle Aged; Observational Studies as Topic
PubMed: 38899545
DOI: 10.1002/14651858.CD013800.pub2 -
The Journal of Vascular Access May 2024Volume flow (Qa) > 1.5-2 l /minQa in arteriovenous accesses may be associated with high flow related systemic or locoregional complications. A variety of surgical... (Review)
Review
Volume flow (Qa) > 1.5-2 l /minQa in arteriovenous accesses may be associated with high flow related systemic or locoregional complications. A variety of surgical techniques are advocated for Qa reduction. Aim of this scoping review is to provide an overview of available evidence regarding the efficacy of this broad spectrum of interventions for Qa reduction in patients with a high flow haemodialysis access. PubMed and Embase were searched according to PRISMA-guidelines. Studies on invasive management of HFA were selected. Inclusion required an English description of surgical techniques in human HFAs including pre- and postoperative access flow-values. Sixty-six studies on 940 patients (mean age 56 years (3-90 years), male 62%, diabetes mellitus 26%, brachial artery-based arteriovenous access 65%) fulfilled inclusion criteria. Performed techniques were banding (58%), revision using distal inflow (12%), plication/anastomoplasty (10%), graft interposition (5%), proximal radial artery ligation (3%), aneurysm repair (4%), or miscellaneous other techniques (8%). Definition of HFA, work-up, indication for surgery and intraoperative monitoring were diverse. All techniques reduced Qa on the short term (mean drop 0.9-1.7 l/min). Secondary access patency rates varied between 70% and 93% (mean follow-up 15 (0-189) months). Definitions of success and recurrence varied widely precluding a comparison of efficacy of techniques. Patient specific factors legitimizing invasive treatment for HFA are discussed. Recommendations on reporting standards when dealing with HFA surgery are provided. In conclusion, the present report on the current management of high flow access does not allow for drawing any definite conclusions due to a lack of standardization in definition, indications for surgical intervention and techniques. Randomized trials comparing different Qa reducing techniques in symptomatic patients are warranted, as are trials comparing a wait-and-see approach versus Qa reduction in asymptomatic patients. As an overview of the variety of techniques was lacking, this scoping review might serve as a map for future researchers.
Topics: Humans; Arteriovenous Shunt, Surgical; Renal Dialysis; Vascular Patency; Treatment Outcome; Middle Aged; Adolescent; Aged; Adult; Male; Young Adult; Risk Factors; Regional Blood Flow; Female; Aged, 80 and over; Child; Child, Preschool; Blood Flow Velocity; Graft Occlusion, Vascular; Time Factors; Blood Vessel Prosthesis Implantation
PubMed: 36428291
DOI: 10.1177/11297298221138361 -
British Journal of Neurosurgery Oct 2023Spinal dural arteriovenous fistulas (SDAVF) are rare with an incidence of 5-10/million annually. They can be difficult to diagnose causing a delay in treatment with... (Review)
Review
BACKGROUND
Spinal dural arteriovenous fistulas (SDAVF) are rare with an incidence of 5-10/million annually. They can be difficult to diagnose causing a delay in treatment with significant morbidity. We describe the first case in the literature of a symptomatic mirror lumbar SDAVF which may go unnoticed due to its unique vascular anatomy.
CASE DESCRIPTION
A 78-year-old gentleman presented with a progressive deterioration in his walking distance and urinary retention. An initial MRI scan of the whole spine did not show features suggestive of an underlying vascular malformation. During further investigations of neurological causes, the patient continued to have progressive symptoms over a 10-month period resulting in a repeat MRI scan. This showed a new finding of cord oedema without abnormal flow voids. He went on to have vascular imaging which demonstrated a mirror L3 SDAVF and underwent subsequent surgical management. At follow up there was a significant improvement in symptoms.
CONCLUSIONS
Completing a systematic review of the literature we find that the mirror lumbar SDAVF in our patient presented in a more aggressive manner with symptoms progressing faster than in single or multi-level SDAVF. Our case demonstrates how this unique vascular anatomy may result in a diagnostic challenge, behaving in an occult way where typical findings are not seen on initial MRI scanning. We provide an argument for early vascular imaging which can result in the treatment of these lesions in a timely manner.
Topics: Male; Humans; Aged; Spine; Magnetic Resonance Imaging; Veins; Arteries; Fistula; Central Nervous System Vascular Malformations; Spinal Cord
PubMed: 33904360
DOI: 10.1080/02688697.2021.1914822 -
The Journal of Vascular Access May 2024Several existing guidelines advocate the access creation without any specific recommendations for those patients over 75 years of age. The aim of this meta-analysis is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Several existing guidelines advocate the access creation without any specific recommendations for those patients over 75 years of age. The aim of this meta-analysis is to compare the outcomes of different vascular access procedures in the sub-group of elderly ESRD patients ⩾75 years of age.
METHODS
A literature search was performed using the MEDLINE and SCOPUS electronic databases. The analysis focused on studies with subgroups of elderly patients ⩾75 years of age with different vascular access procedures, and compared the failure rates of autologous versus prosthetic vascular access. Articles comparing patency rates of distal (forearm) versus proximal upper arm AVFs were also investigated.
RESULTS
Twelve relevant studies were identified and included in the meta-analysis. The pooled results revealed a statistically significant unassisted (primary) failure rate at 24 months in favor of autologous AVFs [odds ratio (OR): 0.56, 95% CI: 0.38-0.83, = 0.003]. A secondary analysis revealed significantly higher 12 months unassisted (primary) and secondary failure rates of forearm AVFs compared with proximal upper arm AVFs (OR: 2.14, 95% CI: 1.53-2.97, < 0.00001 and OR: 1.76, 95% CI: 1.12-2.78, < 0.01 respectively).
CONCLUSION
An increased risk of failure of prosthetic vascular access procedures was found compared with autologous AVFs in patients ⩾75 years of age. Elderly patients ⩾75 years should not be excluded from creation of an autologous access, with proximal upper arm AVFs having better patency rates.
Topics: Aged; Aged, 80 and over; Female; Humans; Male; Age Factors; Arteriovenous Shunt, Surgical; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Chi-Square Distribution; Graft Occlusion, Vascular; Kidney Failure, Chronic; Odds Ratio; Renal Dialysis; Risk Factors; Time Factors; Treatment Outcome; Upper Extremity; Vascular Patency
PubMed: 36447351
DOI: 10.1177/11297298221139059 -
Acta Neurochirurgica Jan 2024Eagle jugular syndrome (EJS), recently identified as a cause of cerebrovascular disease (CVD) due to venous obstruction by an elongated styloid process (SP), is reported...
BACKGROUND
Eagle jugular syndrome (EJS), recently identified as a cause of cerebrovascular disease (CVD) due to venous obstruction by an elongated styloid process (SP), is reported here alongside a case of concurrent de novo cerebral cavernous malformation (CCM). This study aims to explore the potential causal relationship between EJS and de novo CCM through a comprehensive literature review.
METHOD
Systematic literature reviews, spanning from 1995 to 2023, focused on EJS cases with definitive signs and symptoms and de novo CCM cases with detailed clinical characteristics. Data on the pathophysiology and clinical manifestations of EJS, as well as potential risk factors preceding de novo CCM, were collected to assess the relationship between the two conditions.
RESULT
Among 14 patients from 11 articles on EJS, the most common presentation was increased intracranial hypertension (IIH), observed in 10 patients (71.4%), followed by dural sinus thrombosis in four patients (28.6%). In contrast, 30 patients from 28 articles were identified with de novo CCM, involving 37 lesions. In these cases, 13 patients developed CCM subsequent to developmental venous anomalies (43%), seven following dural arteriovenous fistula (dAVF) (23%), and two after sinus thrombosis (6%). In a specific case of de novo brainstem CCM, the development of an enlarged condylar emissary vein, indicative of venous congestion due to IJV compression by the elongated SP, was noted before the emergence of CCM.
CONCLUSION
This study underscores that venous congestion, a primary result of symptomatic EJS, might lead to the development of de novo CCM. Thus, EJS could potentially be an indicator of CCM development. Further epidemiological and pathophysiological investigations focusing on venous circulation are necessary to clarify the causal relationship between EJS and CCM.
Topics: Humans; Brain Stem; Hyperemia; Ossification, Heterotopic; Sinus Thrombosis, Intracranial; Temporal Bone
PubMed: 38231302
DOI: 10.1007/s00701-024-05900-x