Hemodialysis Vascular Access: A Historical Perspective on Access Promotion, Barriers, and Lessons for the Future.

This review describes the history of vascular access for hemodialysis (HD) over the past 8 decades. Reliable, repeatable vascular access for outpatient HD began in the 1960s with the Quinton-Scribner shunt. This was followed by the autologous Brecia-Cimino radial-cephalic arteriovenous fistula (AVF), which dominated HD vascular access for the next 20 years. Delayed referral and the requirement of 1.5-3 months for AVF maturation led to the development of and increasing dependence on synthetic arteriovenous grafts (AVGs) and tunneled central venous catheters, both of which have higher thrombosis and infection risks than AVFs. The use of AVGs and tunneled central venous catheters increased progressively to the point that, in 1997, the first evidence-based clinical practice guidelines for HD vascular access recommended that they only be used if a functioning AVF could not be established. Efforts to promote AVF use in the United States during the past 2 decades doubled their prevalence; however, recent practice guidelines acknowledge that not all patients receiving HD are ideally suited for an AVF. Nonetheless, improved referral for AVF placement before dialysis initiation and improved conversion of failing AVGs to AVFs may increase AVF use among patients in whom they are appropriate.

Low Serum Albumin Levels are Associated with Short-Term Recurrence of Arteriovenous Fistula Failure.

BACKGROUND: Vascular access intervention therapy (VAIVT) is widely used as a treatment for arteriovenous fistula (AVF) failure. However, recurrent AVF failure is a major concern for dialysis patients. By prospectively observing patients after an initial VAIVT, we attempted to identify risk factors for developing restenosis of AVF. METHODS: This single-center prospective study evaluated 57 patients who underwent their first VAIVT procedure at our hospital from April 2022 through March 2023. We performed blood and biochemical tests during the first VAIVT to collect data on clinical variables. Ultrasonography was used to measure vessel diameter reduction rate, flow volume (FV) reduction rate, and increase in resistance index (RI) rate over a 3-month period. RESULTS: Within 3 months, 24 patients developed short-term shunt stenosis and 30 did not. Three were not traceable. In a comparison of the two groups, significant differences were observed in albumin (ALB), FV, RI, and elbow shunt. Analysis of change rates in the three ultrasound findings identified five factors (hematocrit, platelet count, activated partial thromboplastin time, ALB, and FV). The results of logistic regression models revealed that ALB was the most significant predictive factor for short-term shunt stenosis (p = 0.031). CONCLUSION: In conclusion, our findings suggest that low serum ALB at the time of initial VAIVT is a significant risk factor for short-term recurrence of AVF failure in hemodialysis patients. These findings emphasize the importance of careful routine monitoring to reduce the risk of AVF failure and associated complications.

Frequent use of percutaneous transluminal angioplasty is not associated with reduced vascular access recreation in a longitudinal ecology study.

The frequency of percutaneous transluminal angioplasty (PTA) procedures has substantially increased, but its effect on vascular access recreation (VAR) remains inconclusive. We conducted a population-based retrospective analysis of Taiwan hemodialysis (HD) centers from 2004 to 2012. Data was accumulated into center-level characteristics, including patients' demographics, baseline characteristics, PTA procedures, and VAR. Center-level characteristics were summarized annually using appropriate measures. A mixed model assessed the association between PTA frequency and VAR rates, considering within-center correlation and adjusting for potential confounders. A total of 82,005 patients (mean age 62.7 ± 13.9 years, 50.5% male, 48.5% with diabetes mellitus) from 820 HD centers were analyzed. From 2004 to 2012, PTA frequency significantly increased from 1.24 to 3.23 per 1000 HD sessions, while VAR rates did not decline as expected (0.5-0.8 per 1000 HD sessions). Compared with the HD centers of infrequent use of PTA (annual lowest quartile, range 0.39-1.20 per 1000 HD sessions), the ones of frequent use (annual highest quartile, range 2.52-5.10 per 1000 HD sessions) didn't have lower VAR (range 0.54-0.99 vs. 0.50-0.91 per 1000 HD sessions, respectively). After controlling the potential confounders, the HD centers' PTA rates were not significantly associated with lower VAR rates (- 2.6, 95% confidence interval: - 30.3; 25.0, p = 0.85). Frequent use of PTA does not seem to improve VA patency at the center level, with no significant association identified with lower VAR. The indication of PTA in daily practice should be re-evaluated in terms of its efficiency in lowering VAR.

Association of neutrophil-to-lymphocyte ratio and hemodialysis access failure in patients with end stage renal disease: A systematic review and meta-analysis.

This systematic review and meta-analysis aimed to assess the association of neutrophil-to-lymphocyte ratio (NLR) with an elevated risk of vascular access failure in end-stage renal disease (ESRD) patients undergoing hemodialysis. A comprehensive database search of MEDLINE (via PubMed), Scopus, and Cochrane Central was performed. Studies reporting the values of NLR in both functional and non-functional AVF groups in ESRD patients were selected. Quality assessment was performed using the Modified Newcastle-Ottawa scale for observational studies. Meta-analysis was performed using an inverse variance random effects model. Seven observational studies met the inclusion criteria, including 1313 participants with 554 cases and 759 controls. Pooled results showed significantly high NLR levels in patients with non-functional arteriovenous fistula (AVF) compared to functional AVF (SMD = 1.19, 95% CI = 0.74-1.65, p < 0.001). Subgroup analysis confirmed the consistency of the association between NLR and AVF failure across study design (SMD = 1.76, 95% CI = 0.78-2.73, p = 0.0004 in prospective vs SMD = 0.87, 95% CI = 0.42-1.32, p = 0.0001 in retrospective studies), etiology (SMD = 1.63, 95% CI = 0.75-2.52, p = 0.0003 in stenosis or thrombosis; and SMD = 0.80, 95% CI = 0.27-1.34, p = 0.003 in failure to mature of AVF), and NLR measurement timing (SMD = 0.98, 95% CI = 0.42-1.54, p = 0.0006 in preoperative vs SMD = 1.58, 95% CI = 0.47-2.69, p = 0.005 in postoperative NLR). The pooled odds ratio revealed high NLR values as a significant predictor of AVF failure in ESRD patients (OR = 3.91, 95% CI = 1.91-7.98, p = 0.0002). The pooled sensitivity and specificity were 89.72% (95% CI = 77.51%-95.67%) and 72.95% (95% CI = 63.82%-80.47%), respectively. The high NLR is a useful and predictive marker for AVF failure in hemodialysis patients. Future studies should prioritize larger cohort studies to validate and reinforce these observations.

Peripheral intravenous catheter clinical care standard adherence in emergency departments: A qualitative study underpinned by the behaviour change wheel.

AIM: To explore the barriers and facilitators influencing emergency department clinicians' adherence to the Australian Peripheral Intravenous Catheter (PIVC) Clinical Care Standard, using the Behaviour Change Wheel (BCW). BACKGROUND: Suboptimal PIVC practices are frequently linked to a range of patient-important adverse outcomes. The first Australian Peripheral Intravenous Catheter Clinical Care Standard was introduced in 2021, aiming to standardize practice. However, a recent national survey revealed a lack of adherence to the Standard among emergency department clinicians. DESIGN: A qualitative descriptive study. METHOD: The study was conducted across two Australian emergency departments in 2023. Utilizing purposive sampling, semi-structured interviews were conducted. The analysis incorporated both deductive and inductive approaches, mapping the findings to the BCW. FINDINGS: Interviews with 25 nurses and doctors revealed nine key subthemes. The main barriers were the stressful environment, insufficient education and training, and the absence of a feedback mechanism. The main facilitators were recognition of suboptimal practice, belief in the importance of patient engagement, and the desire to improve practice. CONCLUSION: Multiple complex factors have an impact on clinicians' adherence to the Standard. The identified interventions will serve as a guide for future implementation of the Standard. IMPLICATIONS FOR THE PROFESSION AND PATIENT CARE: The findings inform healthcare organizations of the significance of implementing strategies to enhance clinicians' acceptance of the Standard. Clinicians should consider incorporating the multifaceted interventions developed in accordance with the BCW for future implementation projects. IMPACT: Promoting adherence to standards opens avenues to challenge suboptimal practice and has the potential to instigate a culture shift in the fundamental skills of frontline clinicians. REPORTING METHOD: The study is designed and reported according to the Consolidated Criteria for Reporting Qualitative Research checklist. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Impact of arteriovenous fistula aneurysms on a UK dialysis populations' perception of vascular access.

BACKGROUND: Clinically-oriented outcome measures are increasingly being recognized as lacking in consideration of factors important to patients. There is an emerging move of guideline bodies advocating a more patient-centred approach. Aneurysms in autogenous arteriovenous fistula (AVF) can be considered unsightly and a constant reminder for patients of their dependence on dialysis. However, their impact on patient's perception has not previously been reported. METHODS: Between April 2017-18, the Vascular Access Questionnaire (VAQ) was administered to prevalent haemodialysis patients across ten dialysis units via structured interviews, as part of a quality improvement project. Data for the subgroup of patients with aneurysmal AVF (categorised as per classification by Valenti et al.), were retrospectively evaluated and compared to the wider cohort. RESULTS: Data were collected for 539 patients (median age: 66 years; 59% male), of whom 195 (36%) had aneurysmal AVF, with Type 2 morphology (cannulation site) being the most common (75%). Duration of AVF was found to be significantly associated with aneurysmal development, with estimated likelihoods of 11%, 43% and 61% after one, five and ten years, respectively. Interestingly, patients with diabetes had a significantly lower prevalence of aneurysmal development than those that were non-diabetic (25% vs. 43%, p < 0.001). Overall VAQ scores were not found to differ significantly by aneurysm status (p = 0.816) or across morphology types (p = 0.277). However, patients with aneurysmal AVF were significantly more concerned with the appearance of their AVF (p < 0.001) than the wider cohort. Despite this, patients with aneurysmal AVF gave significantly higher scores for satisfaction and ease of use and lower scores for bruising and clotting (p < 0.05). CONCLUSIONS: Aneurysmal AVF are often cited as an important factor by patients for not proceeding with fistula formation. In this evaluation of patient reported experiences, those with aneurysmal AVF reported high satisfaction levels. This may help clinicians highlight positive patient reported outcomes of aneurysmal AVF during preprocedural consent processes.

ESR Essentials: arterial vascular access and closure devices-practice recommendations by the Cardiovascular and Interventional Radiological Society of Europe.

Vascular access is the initial, very important, step of endovascular procedures. Various access sites include the common femoral artery, brachial artery, radial artery, popliteal artery, and distal tibial vessels (pedal arteries). Successful arterial access requires advanced knowledge of anatomy, as well as proper training and experience. Today, vascular access should be obtained using real-time, ultrasound guidance to reduce access time, patient discomfort, and puncture-related complications including dissection, arteriovenous communication, and bleeding. Nevertheless, high-level evidence to support this recommendation in peripheral procedures is limited and level A data are mainly derived from randomized cardiac trials investigating only radial and femoral access. Vascular closure devices (VCDs) for femoral access can be broadly categorized as active closure devices, compression assist devices, and external/topical hemostasis devices. There is high-level evidence demonstrating that their use is related to less time for ambulation and increased patient satisfaction. However, available data failed to clearly demonstrate a benefit in complications compared to standard manual compression in peripheral endovascular arterial procedures, and thrombotic and infectious complications reported following VCD use remain an issue. Heterogeneity noted in the literature, caused by the vast variety of devices, access sites, sheath sizes, clinical scenarios, and procedures, poses difficulties in data analysis and future study design. As a result, an individualized VCD use is currently suggested for ≥ 5 Fr femoral artery access not only to reduce time to hemostasis and ambulation and to improve patient comfort, but also to reduce bleeding complications in cases of femoral access with increased bleeding risk, deranged coagulation, and large-bore access, though a high level of evidence to support this later recommendation is limited. KEY POINTS: US guidance is strongly recommended for femoral access and is mandatory to obtain more challenging access. The use of VCDs for femoral hemostasis is generally safe, effective, and currently supported by level I evidence. Proper training and correct VCD choice, based on the patient's individual characteristics, are imperative to optimize outcomes.

Establishing an autogenous vascular access program in a Guatemalan comprehensive pediatric nephrology center.

BACKGROUND: The Guatemalan Foundation for Children with Kidney Diseases collaborated with Bridge of Life, a not-for-profit charitable organization, to establish a vascular access program. We reviewed our experience with graded surgical responsibility and structured didactic training, creating arteriovenous fistulas (AVF) for Guatemalan children. METHODS: Pediatric vascular access missions were completed from 2015 to 2023 and analyzed retrospectively. Follow-up was completed by the Guatemalan pediatric surgeons, nephrologists, and nursing staff. AVF patency and patient survival were evaluated by Kaplan-Meier life-table analysis with univariate and multivariable association between patient demographic variables by Cox proportional hazards models. RESULTS: Among a total of 153 vascular access operations, there were 139 new patient procedures, forming the study group for this review. The mean age was 13.6 years, 42.6% were female, and the mean BMI was 17.3. Radial or ulnar artery-based direct AVFs were established in 100 patients (71.9%) and ten of the 25 transposition procedures. Brachial artery inflow was required in 29 direct AVFs (20.9%). Two patients underwent femoral vein transpositions. Access-related distal ischemia was not encountered. Seven of the AVF patients later required access banding for arm edema; all had previous dialysis catheters (mean = 9, range 4-12). Primary and cumulative patency rates were 84% and 86% at 12 months and 64% and 81% at 24 months, respectively. The median follow-up was 12 months. Overall patient survival was 84% and 67% at 12 and 24 months, respectively. There were no deaths related to AVF access. CONCLUSIONS: Safe and functional AVFs were established in a teaching environment within a Guatemalan comprehensive pediatric nephrology center.

Vascular Access Complications Following Catheter Ablation of Ventricular Arrhythmias: Impact of Vascular Closure Devices.

BACKGROUND: Vascular access-site complications are the most frequent complications of percutaneous catheter ablation (CA) of ventricular arrhythmias (VAs). Whether arterial/venous vascular closure devices (VCDs) prevent vascular complications is unknown. OBJECTIVE: We investigated the benefit of VCDs in patients undergoing CA of VAs. METHODS: Consecutive CA of VAs were included (2018-2022). Vascular accesses were obtained with ultrasound guidance. At the discretion of the operator, arterial and/or venous VCDs were used. Cases were divided into 3 groups: no use of VCDs for any of the arterial/venous accesses (manual compression - MC), use of VCDs for some but not the all of the accesses (Partial-VCDs), use of VCDs for all of the accesses (Complete-VCDs). Vascular complications were defined minor if they didn't require intervention or major if they required intervention. RESULTS: A total of 1,016 procedures were performed in 872 patients (62±13 years, BMI 30±6 kg/m2, 27% female) during the study period. Femoral arterial access was obtained in 887 procedures (875 single access - 7.4±1.5 Fr size, 12 two accesses - 7.3±3 Fr and 6.9±1.8 Fr). Femoral venous access was obtained in 1,014 procedures (unilateral in 17%, bilateral in 83%, mean N. 2.6±0.7, 8.4±1.3 Fr). Hemostasis was achieved with MC in 192 (19%) procedures, Partial-VCD in 275 (27%), and Complete-VCD in 549 (54%). A vascular complication occurred in 52 (5.1%) procedures, including a minor hematoma in 3.9% and/or a major complication in 1.7%. The rate of vascular complications was 6.8% (5.2% minor and 1.6% major) in the MC group, 7.6% (5.1% minor and 3.3% major) in the Partial-VCD group, and 3.3% (2.9% minor and 0.9% major, P=0.014 for comparison) in the Complete-VCD group. At multivariable analysis, Complete-VCD remained independently associated with lower risk of vascular complications (odds ratio 0.69, 95% confidence interval 0.48 to 0.96, P=0.036). CONCLUSIONS: In patients undergoing CA of VAs, Complete-VCD is associated with lower rates of vascular-related complications compared to MC or Partial-VCD.

"Wire kissing technique" and "externalization and pull-through technique" for treating chronic total occlusion in hemodialysis vascular access: A case report.

The construction and utilization of dependable vascular access are essential for hemodialysis. Despite its importance, complications with vascular access are common, significantly impacting patient morbidity and mortality. This report presents a novel approach to treating chronic total occlusion (CTO) in hemodialysis vascular access using the "wire kissing technique" an "externalization and pull-through technique." An 82-year-old woman on hemodialysis had a thrombotic obstruction in her cephalic vein, which conventional methods failed to address. The wire kissing technique allowed the meeting of antegrade and retrograde wires within the CTO lesion, stabilizing the wire and facilitating balloon passage. The externalization and pull-through technique further enabled the balloon to cross the rigid CTO lesion, successfully completing percutaneous transluminal angioplasty (PTA). Post-procedure ultrasonography showed significant improvements in flow volume and resistance index. These techniques, commonly used in coronary and femoral arteries, have not been previously reported for dialysis vascular access. This case highlights a novel and effective solution for overcoming technical difficulties in crossing CTO lesions, potentially improving outcomes in vascular access for hemodialysis patients.

Placement of tunneled hemodialysis catheters - interventional standard.

While the native arterio-venous fistula (AVF) remains the first choice in vascular access for most hemodialysis patients, tunneled hemodialysis catheters (tHDC) continue to be an option in selected patients. Since timely access to vascular surgery-due to delayed referral or resource limitations-is not always possible, nephrologists have to become more actively involved in planning, creation and monitoring of vascular access. Moreover, this approach could also strengthen patient-centered care in nephrology. This manuscript reviews the current standard in tHDC creation, patient selection and strategies to mitigate the risk of infectious complications and catheter thrombosis. Presentation of novel developments in catheter placement with ultrasound-guided or ECG-guided positioning, their benefits and possible disadvantages emphasizes the complexity of vascular access planning. We offer an approach for choice of insertion method, depending on selected side and existing resources and set focus on the necessity and required resources of 'interventional nephrology' training programs.

Femoral Large Bore Sheath Management: How to Prevent Vascular Complications From Vessel Puncture to Sheath Removal.

Transfemoral access is nowadays required for an increasing number of percutaneous procedures, such as structural heart interventions, mechanical circulatory support, and interventional electrophysiology/pacing. Despite technological advancements and improved techniques, these devices necessitate large-bore (≥12 French) arterial/venous sheaths, posing a significant risk of bleeding and vascular complications, whose occurrence has been related to an increase in morbidity and mortality. Therefore, optimizing large-bore vascular access management is crucial in endovascular interventions. Technical options, including optimized preprocedural planning and proper selection and utilization of vascular closure devices, have been developed to increase safety. This review explores the comprehensive management of large-bore accesses, from optimal vascular puncture to sheath removal. It also discusses strategies for managing closure device failure, with the goal of minimizing vascular complications.

Mind the GAHP: A novel protocol for improved vascular access in the hypotensive patient.

Background: Obtaining intravenous access in hypotensive patients is challenging and may critically delay resuscitation. The Graduated Vascular Access for Hypotensive Patient (GAHP) protocol leverages intraosseous fluid boluses to specifically dilate proximal veins. This study aims to evaluate the efficacy of GAHP in maximizing venous targets through early distal intraosseous access and a small fluid bolus. Methods: This was a prospective randomized cadaveric pilot study to evaluate extremity venous engorgement during intraosseous infusion. Cadavers (n = 23) had an intraosseous needle inserted into four sites: distal radius, proximal humerus, distal femur, and distal tibia. Intraosseous saline was rapidly infused, venous optimization was measured using real-time ultrasound. Primary outcome was maximum vessel circumference increase with intraosseous infusion. Secondary outcomes were: time to maximum circumference, and infusion volume required. Statistical analyses included Levene's test for equality of variances, Wilcoxon signed-rank test, and generalized estimating equation. Results: There was a significant mean increase of 1.03 cm (95% CI 0.86, 1.20), representing a difference of 102%. We found no significant difference in time to optimize vessel circumference across sites, but volume required significantly differed. Conclusion: GAHP quickly and effectively increased the circumference of anatomically adjacent veins. Anatomical sites did not differ on time to reach maximum enlargement of vessels following intraosseous infusion but did differ in terms of volume required to maximize vessel circumference. Further research is needed using live, hypotensive patients.

Assessment of peripheral venous catheters microbiota and its association with phlebitis.

BACKGROUND: Peripheral venous catheters (PVCs) remain the primary mode of short-term venous access for managing intravenous fluid, obtaining blood samples, and peripheral parenteral nutrition. They may get contaminated and require regular monitoring to prevent complications. This study evaluated the occurrence of phlebitis and its associated-clinical and microbiological indicators. METHODS: The frequency of phlebitis was evaluated in hospitalized patients of both medical and surgical fields. Subsequently, the dichotomous association between the presence of phlebitis and the clinical aspects was investigated. In parallel, the bacterial contamination of PVCs was assessed through culture-based methods, microscopy observation, and 16S rRNA gene sequencing. RESULTS: Approximately one in four patients presented phlebitis (28.4%). The most frequent symptom was erythema at access site, with or without pain, corresponding to Score 1 on the phlebitis scale (17.9%). Colonization of both lumen and external surface of PVC was observed in 31.3% of the samples. Staphylococcus and Pseudomonas were the most isolated bacterial genera on the PVC surface. No significant association was observed between the presence of phlebitis and the clinical aspects, as well as the presence of microorganisms. CONCLUSION: Microorganism were present on both internal and external PVC surface, without being associated to phlebitis.

Anatomical Feasibility of Percutaneous Arteriovenous Fistula Formation in Korea.

INTRODUCTION: Currently, there are two types of percutaneous arteriovenous fistula (pAVF) formation systems approved by the FDA: Ellipsys and WavelinQ. Although these systems are already in use in Europe or the United States, they have not been approved for use in Korea yet. For this reason, this study aimed to check anatomical feasibility of these systems for Korean population prior to their actual use. METHODS: Consecutive patients who received ultrasound vein mapping for arteriovenous fistula formation from June 2021 to June 2022 were included. The anatomical feasibility of each system was confirmed according to the manufacturer's instructions for use (IFU). RESULTS: Upper extremity ultrasonography was performed for a total of 83 patients to determine their feasibility for pAVF formation. Of these patients, 65.1% were feasible for pAVF formation with appropriate deep communicating vein (DCV) and outflow. Among them, 57.8% were feasible for the Ellipsys system and 54.2% were feasible for the WavelinQ system. Most patients who were infeasible for pAVF formation had a DCV of small size. Ulnar vessels were more suitable than radial vessel for WavelinQ (54.2% vs 33.7%, P-value = .012). The most common reason for not meeting the criteria was a small vein size at the access site. CONCLUSIONS: More than half of all patients were feasible for pAVF formation in this study. Ellipsys had a higher feasibility than WavelinQ, although they showed no significant difference in the feasibility. If these devices are imported into Korea, it will be a good opportunity for many patients to reduce the surgical burden and create AVFs more easily through these procedures.

Factors affecting suboptimal maturation of autogenous arteriovenous fistula in elderly patients with diabetes:A narrative review.

Autogenous arteriovenous fistula (AVF) is considered the preferred vascular access choice for individuals undergoing maintenance hemodialysis (MHD) and is widely utilized in China, as reported by the Dialysis Outcomes and Practice Patterns Study. Despite its popularity, the significant incidence of poor AVF maturation often leads to the need for central venous catheter insertion, increasing the risk of complications like superior vena cava stenosis and catheter-related infections, which in turn raises the overall mortality risk. With the prevalence of diabetes rising globally among the elderly and diabetic kidney disease being a leading cause of end-stage renal disease necessitating renal replacement therapy, our retrospective review aims to explore the various factors affecting AVF maturation in this specific patient population. While there have been numerous studies examining AVF complications in MHD patients, including issues like failure, patency loss, stenosis, thrombosis, poor maturation, and other influencing factors, there remains a gap in large-scale clinical studies focusing on the incidence and risk factors for immature AVF specifically in elderly diabetic patients. This paper delves into the pathophysiological mechanisms, diagnostic criteria, and unique considerations surrounding AVF maturation in elderly diabetic patients, distinguishing them from the general population. Our literature review reveals that elderly diabetic patients exhibit a higher risk of AVF immaturity compared to the general population. Additionally, there exists a continuing discourse regarding several aspects related to this group, including the choice of dialysis access, timing of AVF surgery, and surgical site selection. Furthermore, we delve into the management strategies for vascular access within this specific group with the goal of providing evidence-based guidance for the establishment and maintenance of functional vascular access in elderly diabetic patients.

Peripheral venous dilation using flow-mediated dilation response: A randomized crossover study.

BACKGROUND: Venodilation is crucial in enhancing the success rate of peripheral intravenous cannulation. Flow-mediated dilation (FMD) is a vasodilatory response initiated by temporary ischemia followed by reperfusion. This crossover study aimed to test the hypothesis that FMD induces dilation of the peripheral veins of the forearm. METHODS: Fifteen healthy volunteers underwent the FMD and control conditions in a randomized order. FMD involved a 5-min occlusion of blood flow in the brachial artery, followed by reperfusion, achieved by inflating and deflating a cuff placed on the upper arm. The control condition involved participants remaining at rest. The primary outcome measure was a change in the cross-sectional area of the cephalic vein post-intervention. The secondary outcomes included changes in venous diameter and perfusion index (PI). RESULTS: FMD significantly increased the cross-sectional area of the cephalic vein compared with the control condition (relative change to baseline: 37.7% (31.4) vs 2.2% (11.7)), with a mean difference of 35.4% (95% confidence interval (CI): 16.4-54.5, p = 0.001). Both longitudinal and transverse diameters were significantly expanded with FMD compared to the control (relative change to baseline: 15.7% (15.4) vs 2.6% (3.6), p = 0.004; 18.9% (15.6) vs -0.0 (10.2), p = 0.003, respectively). Additionally, PI significantly increased with FMD compared with the control (relative change to baseline: 77.8% (56.9) vs 14.6% (36.0)), with a mean difference of 63.2% (95% CI: 31.2-95.2, p = 0.001). CONCLUSION: FMD application induced dilation of the cephalic vein of the forearm. The findings suggest that FMD is an effective technique for dilating the venous area and potentially improving the success rate of peripheral intravenous cannulation.

SURgical vs. PERcutaneous ACCESS in Transfemoral Transcatheter Aortic Valve Implantation (SU-PER-ACCESS Study).

Background: The transfemoral (TF) approach is the most common route in TAVI, but it is still associated with a risk of bleeding and vascular complications. The aim of this study was to compare the clinical outcomes between surgical cut-down (SC) and percutaneous (PC) approach. (2) Methods: Between January 2018 and June 2022, 774 patients underwent a transfemoral TAVI procedure. After propensity matching, 323 patients underwent TAVI in each group. (3) Results: In the matched population, 15 patients (4.6%) in the SC group vs. 34 patients in the PC group (11%) experienced minor vascular complications (p = 0.02), while no difference for major vascular complication (1.5% vs. 1.9%) were reported. The rate of minor bleeding events was higher in the percutaneous group (11% vs. 3.1%, p <.001). The SC group experienced a higher rate of non-vascular-related access complications (minor 8% vs. 1.2%; major 2.2% vs. 1.2%; p < 0.001). (4) Conclusions: SC for TF-TAVI did not alter the mortality rate at 30 days and was associated with reduced minor vascular complication and bleeding. PC showed a lower rate of non-vascular-related access complications and a lower length of stay. The specific approach should be tailored to the patient's clinical characteristics.

Patency rates following treatment with the WRAPSODY™ Cell-Impermeable Endoprosthesis for recalcitrant renal access circuit dysfunction: Results from a tertiary Australian centre.

OBJECTIVE: To describe clinical outcomes associated with the use of the WRAPSODY Cell-Impermeable Endoprosthesis at a tertiary center in Western Australia. METHODS: Patients with recalcitrant occlusive disease in the venous outflow of their arteriovenous access circuits were treated with WRAPSODY. Patients were prospectively followed up to 12-month post-procedure. Study measures included 30-day adverse events, technical success, target lesion primary patency, access circuit primary patency, and assisted access circuit primary patency. RESULTS: Twenty-seven WRAPSODY devices were used to treat 15 consecutive patients. The technical success rate was 100%. No device-related adverse events were observed during the follow-up period. Two patients did not complete the full follow up. Patency rates at 3-, 6-, and 12 months for target lesion primary patency were 100% (15/15), 100% (15/15), and 100% (13/13), respectively. Rates for access circuit primary patency at 3-, 6-, and 12 months were 73.3% (11/15), 46.7 % (7/15), and 46.2% (6/13), respectively. Edge stenosis was observed in 33.3% (5/15) of cases and accounted for 5 of the 8 patients who experienced failed access circuit primary patency on angiogram. Primary assisted functional patency was 100% at 12 months. CONCLUSION: WRAPSODY can be utilized safely and has durable patency in real-world patients with complex anatomical renal access stenotic lesions. The therapeutic benefits associated with the device may encourage broader use in clinical practice.

Optimising central venous catheter placement by comparing cavoatrial junction position to chest X-ray landmarks: A cross-sectional study using CT chest reconstruction.

INTRODUCTION: Central venous catheter (CVC) tip placement guided by chest X-ray (CXR) landmarks is currently prone to inconsistency and malpositioning. This study aims to better define the relationship between the cavoatrial junction (CAJ) and selected X-ray landmarks. METHODS: Chest CTs of 100 patients were retrospectively assessed. CT images were converted to a 'virtual CXR' using a digital workstation, enabling simultaneous localisation of the CAJ and evaluation of CXR landmarks. Vertical distances between the CAJ and selected landmarks were measured for each patient. Measurements were assessed for correlation with age and compared between age groups and sexes. RESULTS: The mean vertical distance of the following landmarks above the CAJ was found: the carina (46.2 mm), the intersection of the bronchus intermedius and the right heart border (7.6 mm) and the superior inflection of the right heart border (Sup-RHB) (13.0 mm). The maximum lateral bulge of the right heart border (Lat-RHB) was 18.4 mm below the CAJ. A new landmark: the mid-superior right heart border, defined as the mid-point between the Sup-RHB and Lat-RHB, was the closest to the CAJ, lying 2.6 mm below the CAJ. CONCLUSION: We propose that the CVC tip can be placed at the mid-superior right heart border landmark.