New Innovations and Devices in the Management of Chronic Limb-Threatening Ischemia.

As the number of patients afflicted by chronic limb-threatening ischemia (CLTI) continues to grow, new solutions are necessary to provide effective, durable treatment options that will lead to improved outcomes. The diagnosis of CLTI remains mostly clinical, and endovascular revascularization remains mostly balloon-based. Multiple innovative techniques and technologies are in development or in early usage that may provide new solutions. This review categorizes areas of advancement, highlights recent developments in the management of CLTI and looks forward to novel devices that are currently under investigation.

Dialysis access as a source of infective endocarditis in dialysis patients.

The incidence of Infective Endocarditis (IE) is higher in dialysis patients compared to the general population. A major risk factor for IE in this group stems from bacterial invasion during repeated vascular access. Previous studies have shown increased risk of bacteremia in patients with indwelling dialysis catheters compared to permanent vascular access. However, association between the development of IE and the type of dialysis access is unclear. We aimed to examine the associated types of intravascular access and route of infection in dialysis patients who were admitted with infective endocarditis at our center. All patients admitted to Albert Einstein Medical Center in Philadelphia with a diagnosis of infective endocarditis who were on chronic hemodialysis were identified from the hospital database for the period of 1/1/07 to 12/31/18. Modified Duke criteria was used to confirm the diagnosis of infective endocarditis. A total of 96 cases were identified. Of those, 57 patients had an indwelling dialysis catheter while the other 39 had permanent dialysis access. In 82% of patients with dialysis catheters, their dialysis access site was identified as the primary source of infection compared to 30% in those with permanent dialysis access (p<0.001). The number of dialysis catheters placed in the preceding 6 months was strongly associated with endocarditis resulting from the dialysis access site (OR = 3.202, p=0.025). Dialysis catheters are more likely to serve as the source of infection in dialysis patients developing IE compared to permanent dialysis access. Increased awareness of risk of IE associated with dialysis catheters is warranted.

Vascular access for hemodialysis: A perpetual challenge.

Vascular access for hemodialysis has a long and rich history. This article highlights major innovations and milestones in the history of angioaccess for hemodialysis. Advances in achievement of lasting hemodialysis access, swift access transition, immediate and sustaining access to vascular space built the momentum at different turning points of access history and shaped the current practice of vascular access strategy. In the present era, absent of large-scale clinical trials to validate practice, the ever-changing demographic and comorbidity makeup of the dialysis population pushes against stereotypical angioaccess goals. The future of hemodialysis vascular access would benefit from proper randomized clinical trials and acclimatization to clinical contexts.

Variables associated with successful vascular access cannulation in hemodialysis patients: a prospective cohort study.

BACKGROUND: Successful vascular access (VA) cannulation is integral to the delivery of adequate dialysis, highlighting the importance of ensuring the viability of arteriovenous access in hemodialysis (HD) patients. Missed VA cannulation can lead to infection, infiltration, hematoma or aneurysm formation resulting in the need for access revision, central venous catheter (CVC) placement, or permanent loss of VA. Cannulation-related complications can also negatively impact on a patient's dialysis experience and quality of life. This study aimed to identify patient, VA and nurse factors associated with unsuccessful VA cannulations. METHODS: A prospective cohort study was conducted in HD patients with a permanent VA from three HD units. Data on patient, VA and nurse characteristics, plus, cannulation technique were collected for each episode of cannulation. General Estimating Equation was used to fit a repeated measures logistic regression to determine the odds of cannulation success. RESULTS: We collected data on 1946 episodes of cannulation (83.9% fistula) in 149 patients by 63 nurses. Cannulation included use of tourniquet (62.9%), ultrasound (4.1%) and was by rope ladder (73.8%) or area (24.7%) technique. The miscannulation rate was 4.4% (n = 85) with a third of patients (n = 47) having at least one episode of miscannulation. Extravasation (n = 17, 0.9%) and use of an existing CVC (n = 6, 0.6%) were rare. Multivariable characteristics of successful cannulation included fistula compared with graft [OR 4.38; 95%CI, 1.89-10.1]; older access [OR 1.68; 95%CI, 1.32-2.14]; absence of stent [OR 3.37; 95%CI, 1.39-8.19]; no ultrasound [OR 13.7; 95%CI, 6.52-28.6]; no tourniquet [OR 2.32; 95%CI, 1.15-4.66]; and lack of post graduate certificate in renal nursing [OR 2.27; 95%CI, 1.31-3.93]. CONCLUSION: This study demonstrated a low rate of miscannulation. Further research is required on ultrasound-guided cannulation. Identifying variables associated with successful cannulation may be used to develop a VA cannulation complexity instrument that could be utilised to match to the cannulation skill of a competency-assessed nurse, thereby minimising the risk of missed cannulation and trauma.

Building a Global, Pediatric Vascular Access Registry: A Scoping Review of Trial Outcomes and Quality Indicators to Inform Evidence-Based Practice.

BACKGROUND: Internationally, there is a lack of comparative vascular access (VA) data for pediatric clinicians and organizations to benchmark outcomes, evaluate quality initiatives, and improve practice. A VA registry is needed to address these knowledge and data capture gaps. OBJECTIVES: To determine the range and heterogeneity of VA outcome measures or quality indicators reported in randomized controlled trials (RCTs) and clinical registries, to inform development of a homogeneous, reliable, minimum dataset for a pediatric VA registry. METHODS: Scoping review framework. A systematic search for RCTs reporting VA outcomes in pediatrics and neonates was undertaken in the Cochrane library, EMBASE, CINAHL, PubMed, MEDLINE, and EBSCO using a medical subject headings and key words related to VA and pediatrics. We included RCTs of children (0-18 years) reporting any VA outcome. We identified clinical registries reporting VA data in children (0-18) through web-based searches using key words related to VA and clinical or quality registries. Additional registries were identified through peer consultation. The frequency and scope of outcome measures and quality indicators were extracted from trials and registries and evaluated. RESULTS: From 93 RCTs included, 214 different VA measures were reported, reflecting 14 outcome domains. The most commonly reported outcome domains were insertion (44 RCTs; 47%), noninfectious complications (33 RCTs; 35%), and infectious complications (30 RCTs; 32%). Of the 22 registries identified, VA-associated infection was the main quality indicator routinely collected (12 registries; 55%). Outcomes such as mechanical complications and patient-reported outcomes were infrequently collected. LINKING EVIDENCE TO ACTION: Vascular access outcomes reported in pediatric and neonatal RCTs are highly heterogeneous. Internationally, clinical registries currently collect minimal VA data with the exception of infection outcomes. A core dataset of reliable, relevant measures to children and clinicians for VA device quality is needed. This will enable a VA registry that facilitates inter-institutional and international benchmarking.

Drug-coated balloon versus standard percutaneous transluminal angioplasty for the treatment of superficial femoral and popliteal peripheral artery disease: 12-month results from the IN.PACT SFA randomized trial.

BACKGROUND: Drug-coated balloons (DCBs) have shown promise in improving the outcomes for patients with peripheral artery disease. We compared a paclitaxel-coated balloon with percutaneous transluminal angioplasty (PTA) for the treatment of symptomatic superficial femoral and popliteal artery disease. METHODS AND RESULTS: The IN.PACT SFA Trial is a prospective, multicenter, single-blinded, randomized trial in which 331 patients with intermittent claudication or ischemic rest pain attributable to superficial femoral and popliteal peripheral artery disease were randomly assigned in a 2:1 ratio to treatment with DCB or PTA. The primary efficacy end point was primary patency, defined as freedom from restenosis or clinically driven target lesion revascularization at 12 months. Baseline characteristics were similar between the 2 groups. Mean lesion length and the percentage of total occlusions for the DCB and PTA arms were 8.94 ± 4.89 and 8.81 ± 5.12 cm (P=0.82) and 25.8% and 19.5% (P=0.22), respectively. DCB resulted in higher primary patency versus PTA (82.2% versus 52.4%; P<0.001). The rate of clinically driven target lesion revascularization was 2.4% in the DCB arm in comparison with 20.6% in the PTA arm (P<0.001). There was a low rate of vessel thrombosis in both arms (1.4% after DCB and 3.7% after PTA [P=0.10]). There were no device- or procedure-related deaths and no major amputations. CONCLUSIONS: In this prospective, multicenter, randomized trial, DCB was superior to PTA and had a favorable safety profile for the treatment of patients with symptomatic femoropopliteal peripheral artery disease. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique Identifiers: NCT01175850 and NCT01566461.

Trends in US Vascular Access Use, Patient Preferences, and Related Practices: An Update From the US DOPPS Practice Monitor With International Comparisons.

BACKGROUND: Since the bundled end-stage renal disease prospective payment system began in 2011 in the United States, some hemodialysis practices have changed substantially, raising the question of whether vascular access practice also has changed. We describe monthly US vascular access use from August 2010 to August 2013 with international comparisons, and other aspects of US vascular access practice. STUDY DESIGN: Prospective observational cohort study of vascular access. SETTING & PARTICIPANTS: Maintenance hemodialysis patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS) Practice Monitor (DPM) in the United States (N=3,442; US patients) and 19 other nations (N=8,478). PREDICTORS: Country, patient demographics, time period. OUTCOMES: Vascular access use, pre-end-stage renal disease access timing of first nephrologist care and arteriovenous access placement, patient self-reported vascular access preferences (United States only), treatment practices as stated by medical directors. RESULTS: In the United States from August 2010 to August 2013, arteriovenous fistula (AVF) use increased from 63% to 68%, while catheter use declined from 19% to 15%. Although AVF use did not differ greatly across age groups, arteriovenous graft use was 2-fold higher among black (26%) versus nonblack US patients (13%) in 2013. Across 20 countries in 2013, AVF use ranged from 49% to 92%, whereas catheter use ranged from 1% to 45%. Patient-reported vascular access preferences differed by sex and race, with 16% to 20% of patients feeling uninformed regarding benefits/risks of different vascular access types. Among new (incident) US hemodialysis patients, AVF use remains low, with ∼70% initiating hemodialysis therapy with a catheter (60% starting with catheter when having ≥4 months of predialysis nephrology care). In the United States, longer typical times to first AVF cannulation were reported. LIMITATIONS: Noncompletion of surveys may affect the generalizability of findings to the wider hemodialysis population. CONCLUSIONS: AVF use has increased, with catheter use decreasing among prevalent US hemodialysis patients since the introduction of the prospective payment system. However, AVF use at dialysis therapy initiation remains low, suggesting that reforms affecting predialysis care may be necessary to incentivize improvements in fistula rates at dialysis therapy initiation as achieved for prevalent hemodialysis patients.

Venous access in children: state of the art.

PURPOSE OF REVIEW: The aim of this review is to discuss recent developments in vascular access technology and to highlight those that are particularly relevant to the practitioner. RECENT FINDINGS: The need for venous access should always be critically assessed in every child, and it is important to use the limited number of suitable veins wisely and to avoid unnecessary attempts. Near-infrared devices make veins visible, but they do not necessarily increase the success rate of peripheral venous puncture. In contrast, ultrasound is now almost universally used for central venous puncture, and it helped to popularize the supraclavicular puncture of the left anonymous vein. The focus has shifted more toward infectious and especially thrombotic complications. SUMMARY: Despite the development of new technical devices, successful venous puncture remains heavily dependent on the skills of the operator.

The evolution of pediatric continuous renal replacement therapy.

The provision of continuous renal replacement therapies (CRRT) to small children has generally required the adaptation of adult machines and modified operational characteristics. CRRT prescription for younger and smaller children versus adults differs significantly due to problems concerning the extracorporeal blood volume, the need for circuit blood priming, and the adaptation of machines designed for adult-sized patients. Moreover, the provision of renal replacement therapy to infants and neonates presents a unique problem: no more than 10-15% of their blood volume should be removed by the extracorporeal circuit to prevent hypotension and anemia. In 2012, a dedicated machine, i.e. the Cardio-Renal, Pediatric Dialysis Emergency Machine (CARPEDIEM), was developed and launched the 'fitted era' for pediatric CRRT. In this review, we analyze how CRRT techniques have evolved for pediatric application and describe the first in vivo application of the CARPEDIEM for the safe and efficacious provision of CRRT to infants.

Totally implantable vascular access devices 30 years after the first procedure. What has changed and what is still unsolved?

The first placement of a totally implantable central venous access device (TIVAD) was performed in 1982 at the MD Anderson Cancer Center in Houston by John Niederhuber, using the cephalic vein­exposed by surgical cut-down­as route of access to central veins. After that, TIVADs proved to be safe and effective for repeated administration of drugs, blood, nutrients,and blood drawing for testing in many clinical settings, especially in the oncologic applications. They allow for administration of hyperosmolar solutions, extreme pH drugs, and vescicant chemotherapeutic agents,thus improving venous access reliability and overall patients' quality of life. Despite the availability of a variety of devices, each showing different features and performances, many issues are still unsolved. The aim of this review article is to point out what has changed since the first implant of a TIVAD, and what it is still matter of debate, thus needing more investigation. Topics analyzed here include materials, choice of the veins and techniques of implantation, role of ultrasound (US) guidance in central venous access, position of catheter tip assessment, TIVAD-related infection and thrombosis, and quality of life issues.

An innovative approach to near-infrared spectroscopy using a standard mobile device and its clinical application in the real-time visualization of peripheral veins.

BACKGROUND: Excessive venipunctures are a significant problem both in emergency rooms and during hospital stays. Near-infrared (NIR) illumination devices improve venipuncture success rate but their usage is limited by their availability and economic cost. The objectives of this study were to develop a low-cost NIR spectroscopy prototype from a standard mobile device, to evaluate its efficacy and acceptance as an educational tool, and in a clinical setting. METHODS: Through a user-centric design process a prototype device was developed. Its educational efficacy was evaluated through a non-invasive, observational study (20 student clinicians, 25 subjects) and its acceptance was assessed using quantitative and qualitative analysis. A smaller clinical trial was performed by a group of 4 medical professionals over a period of 6 weeks that involved 64 patients. RESULTS: The prototype enables real-time visualization of peripheral veins on a variety of Android-based devices. The prototype was 35.2% more successful in visualizing and locating veins (n = 500 attempts) than the nursing students. The acceptance assessment revealed high perception of usefulness, satisfaction, and ease of use. In the clinical trial, 1.6 (SD 1.3) additional veins per patient were identified compared with the traditional visualization methods. CONCLUSIONS: To the best of our knowledge this is the first study that describes the design, feasibility and application of an NIR spectroscopy prototype developed on a standard mobile device.

Advances and directions in chemotherapy using implantable port systems for colorectal cancer: a historical review.

With the recent advances in chemotherapy for colorectal cancer, the prognosis for patients with metastatic colorectal cancer has been significantly improved. The development of the implantable port system has also enabled patients to receive multiagent chemotherapy with a more satisfactory quality of life. Historically, chemotherapy using implantable port systems was begun to obtain an oncological benefit in the treatment of locoregional cancer. In the 1950s, there was an increasing interest in perfusion techniques for the application of chemotherapeutic agents, such as nitrogen mustard, in the locoregional treatment of metastatic cancer. Among them, the treatment of liver metastasis has interested oncologists for many years. On the other hand, implantable devices were developed during the intervening decades that have enabled patients with colorectal cancer with liver metastases to be treated effectively using hepatic arterial infusion; which became more common in the 1980s. The treatment of metastatic colorectal cancer increasingly requires a multimodal approach and multiple treatment options based not on convenience, but in terms of personalization and efficacy. Therefore, it is important to optimize the pharmacokinetics of chemotherapeutic agents. Implantable port systems for colorectal cancer patients have been essential for oncological practice, and the importance of these systems will remain unchanged in the near future.

Free p-cresol sulfate is associated with survival and function of vascular access in chronic hemodialysis patients.

BACKGROUND: Protein-bound uremic toxins indoxyl sulfate (IS) and p-cresol sulfate (p-CS) have been implicated as an important factor in uremic syndrome. Recent evidence indicates that both IS and p-CS are predictors of cardiovascular as well as all-cause mortality among chronic dialysis patients. We conducted a study to analyze the relationship between IS and p-CS and vascular access (VA) outcome in chronic hemodialysis (HD) patients. METHODS: A total of 91 chronic stable HD patients were divided into groups according to survival of VA and frequency of VA dysfunction. Demographic and biochemical data were reviewed and recorded. Serum levels of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1, and the total and free forms of IS and p-CS were determined. RESULTS: Patients with a history of frequent VA failure and dysfunction had lower albumin and higher levels of ICAM-1, free IS, free and total p-CS. Diabetes was associated with higher IS and p-CS. Logistic regression revealed that diabetes and free p-CS were independent factors associated with poor outcome of VA. CONCLUSION: Endothelial dysfunction and uremic toxins were associated with survival and function of VA. Diabetes and free p-CS were significantly related to the outcome of VA among chronic HD patients.

Implementation of an Evidence-Based Practice Change Removing Heparin From Implanted Vascular Access Devices.

The objective of this article was to describe the implementation and outcomes of an evidence-based practice change to remove heparin from implanted vascular access device (IVAD) management. An extensive search of the literature was performed, and articles were appraised and synthesized to determine the best practice. A common theme emerged from the literature, showing that 0.9% sodium chloride alone can be as effective as heparin in preventing occlusion in IVADs. In this nurse-led initiative, heparin was successfully removed from the IVAD deaccess process and replaced with a 0.9% sodium chloride flush using a pulsatile flushing technique. Alteplase administration rates were used to measure success of the project, with no statistically significant change observed in alteplase rates 6 mo postimplementation. Successful implementation of this practice change demonstrates that 0.9% sodium chloride may be used for IVAD lock when deaccessing.

Trends in interventional stroke device utilization during the COVID-19 pandemic.

OBJECTIVES: The collateral effect of the COVID-19 pandemic on interventional stroke care is not well described. We studied this effect by utilizing stroke device sales data as markers of interventional stroke case volume in the United States. METHODS: Using a real-time healthcare device sales registry, this observational study examined trends in the sales of thrombectomy devices and cerebral aneurysm coiling from the same 945 reporting hospitals in the U.S. between January 22 and June 31, 2020, and for the same months in 2018 and 2019 to allow for comparison. We simultaneously reviewed daily reports of new COVID-19 cases. The strength of association between the cumulative incidence of COVID-19 and procedural device sales was measured using Spearman rank correlation coefficient (CC). RESULTS: Device sales decreased for thrombectomy (- 3.7%) and cerebral aneurysm coiling (- 8.5%) when comparing 2019-2020. In 2020, thrombectomy device sales were negatively associated with the cumulative incidence of COVID-19 (CC - 0.56, p < 0.0001), with stronger negative correlation during April (CC - 0.97, p < 0.0001). The same negative correlation was observed with aneurysm treatment devices (CC - 0.60, p < 0.001), with stronger correlation in April (CC - 0.97, p < 0.0001). CONCLUSIONS: The decline in sales of stroke interventional equipment underscores a decline in associated case volumes. Future pandemic responses should consider strategies to mitigate such negative collateral effects.

Dialysis Access: At the Intersection of Policy, Innovation, and Clinical Care.

The Advancing American Kidney Health executive order aims to reduce the incidence of end-stage kidney disease, promote home dialysis therapies, increase the number of kidney transplants, and encourage innovation in new technologies, evidence-based practice, and early detection of kidney disease. Improvements in dialysis access care are essential to the success and expansion of this program, and to being able to provide high-quality, cost-efficient care to this patient population. Specifically, the need for expanded access to home dialysis will require surgeons and interventionalists to become proficient and trained in peritoneal dialysis catheter placement and for the referral process to be streamlined to accommodate the increased interest in this modality. In addition, new technologies, namely percutaneous fistula creation, bioengineered vessels, and a variety of interventions to reduce arteriovenous stenosis, will hopefully allow for timely and durable vascular access options that will support implementation of the executive order.

Recent Advances in Arteriovenous Access Creation for Hemodialysis: New Horizons in Dialysis Vascular Access.

Recent advances in technology show promise in providing greater vascular access options for hemodialysis patients. This review discusses novel methods for creating an anastomosis for arteriovenous (AV) fistulas and new materials for prosthetic AV grafts. Two technologies for endovascular arteriovenous fistula creation, the Ellipsys and WavelinQ endovascular systems, are discussed. When an AV fistula is not possible, an AV graft or devices to augment the AV fistula may be appropriate. New materials that have been developed that show promise as an alternative to the expanded polytetrafluoroethylene graft are discussed. Such potential conduits include bioengineered vessels and both allogenic or xenogenic biologic grafts. Devices designed to optimize blood flow to reduce maturation failure and improve AV fistula outcomes are explored.

Challenges of Vascular Access in the Pediatric Population.

The incidence and prevalence of renal replacement therapy has continued to increase in the pediatric population. Recent data have shown that hemodialysis was the most frequently used dialysis modality, especially in pediatric ESRD patients (age 0-21 years). A well-functioning vascular access is required for effective hemodialysis and choosing the best vascular access option for pediatric patients can be difficult. Pediatric vascular options include arteriovenous fistula, arteriovenous graft, and central venous catheters (CVCs). There is a national initiative for fistula first-catheter last approach; however, CVCs have been reported as the most conventionally utilized vascular access option in pediatric patients. The use of CVCs should be minimized or avoided as they are associated with high risk of infections, thrombosis, and other complications. Thus, it is important for practitioners to plan appropriately in advance, practice good clinical judgment, and assure that the best vascular access is placed according to the patient's needs. Therefore, this article reviews the different types of pediatric vascular access and the associated benefits and potential complications of each.

Peripherally inserted central catheter ports: A vascular access specialist's systematic approach.

Implanted ports are an important vascular access device for patients with malignancies requiring long-term chemotherapy. Peripherally placed ports are increasing in use as they are a safe, cost-effective alternative to chest-placed ports. Most peripheral ports can be placed bedside by specialist nurses in designated clinical areas rather than costly operating rooms or interventional radiology suites. Peripheral ports are considered less invasive compared with chest port placement because of reduced procedural risk. To enhance the success rate of peripheral port placement and minimize risks, we provide vascular access specialists with a systematic approach along with some technical advice tips and tricks to help avoid mechanical complications such as repeated puncture of the vein, excessive bleeding, thrombosis or skin dehiscence, as well as latent complications such as catheter migration and catheter-related blood stream infection.