Vascular Access Problems Research Articles

Endovascular treatment of dysfunctional arteriovenous fistula in hemodialyzed patients — the results of one year follow-up

Introduction. The arteriovenous fistula (AVF) dysfunction is a common reason for vascular access problem in chronically hemodialyzed patients. It is caused by stenosis or occlusion located either in inflow artery, anastomosis or outflow vein. Revascularization of these pathologies can be achieved in surgical or endovascular (PTA) manner. The aim of this study was to evaluate both immediate and late endovascular treatment results of dysfunctional fistulas in chronically hemodialyzed patients. Material and methods. We included in our observation 106 patients with end stage renal disease, who un-derwent PTA within arteriovenous fistulas. We used conventional and unified techniques of endovascular therapy. Procedural results were evaluated after 1, 3, 6 and 12 months based on fistula sufficiency during hemodialysis. Results. In 96 (90.6%) cases the initial result of PTA was good. We achieved improvement in blood flow through AVF and successful hemodialysis. In 10 cases (9.4%) results were not satisfactory. None of our patients developed neither worsening in the blood flow through AVF nor compromised blood circulation distally to AVF. No serious complications (MI, stroke, death) occurred during procedure or hospital stay. After 12 months, in 52 patients AVF were functioning properly. In 20 cases, because of fistula dysfunction, reintervention was necessary (primary patency 66%). Considering all patients, also these with successful reintervention, 69 AVF were functioning properly after 12 months (secondary patency 86%). Conclusions. To conclude, the immediate and long-term PTA outcomes of arteriovenous fistulas with currently available techniques and equipment are satisfying. PTA is a safe manner of prolonging patency rate of AVF in patients requiring permanent hemodialysis.

Developing a Set of Core Outcomes for Trials in Hemodialysis: An International Delphi Survey

Survival and quality of life for patients on hemodialysis therapy remain poor despite substantial research efforts. Existing trials often report surrogate outcomes that may not be relevant to patients and clinicians. The aim of this project was to generate a consensus-based prioritized list of core outcomes for trials in hemodialysis. In a Delphi survey, participants rated the importance of outcomes using a 9-point Likert scale in round 1 and then re-rated outcomes in rounds 2 and 3 after reviewing other respondents' scores. For each outcome, the median, mean, and proportion rating as 7 to 9 (critically important) were calculated. 1,181 participants (202 [17%] patients/caregivers, 979 health professionals) from 73 countries completed round 1, with 838 (71%) completing round3. Outcomes included in the potential core outcome set met the following criteria for both patients/caregivers and health professionals: median score≥ 8, mean score≥ 7.5, proportion rating the outcome as critically important≥ 75%, and median score in the forced ranking question<10. Patients/caregivers rated 4 outcomes higher than health professionals: ability to travel, dialysis-free time, dialysis adequacy, and washed out after dialysis (mean differences of 0.9, 0.5, 0.3, and 0.2, respectively). Health professionals gave a higher rating for mortality, hospitalization, decrease in blood pressure, vascular access complications, depression, cardiovascular disease, target weight, infection, and potassium (mean differences of 1.0, 1.0, 1.0, 0.9, 0.9, 0.8, 0.7, 0.4, and 0.4, respectively). The Delphi survey was conducted online in English and excludes participants without access to a computer and internet connection. Patients/caregivers gave higher priority to lifestyle-related outcomes than health professionals. The prioritized outcomes for both groups were vascular access problems, dialysis adequacy, fatigue, cardiovascular disease, and mortality. This process will inform a core outcome set that in turn will improve the relevance, efficiency, and comparability of trial evidence to facilitate treatment decisions.

Randomized phase II trial of sipuleucel-T immunotherapy preceded by sensitizing radiation therapy and sipuleucel-t alone in patients with metastatic castrate resistant prostate cancer.

222 Background: Sipuleucel-T (sip-T) is an autologous cellular vaccine indicated for patients (pts) with asymptomatic or minimally symptomatic metastatic castration resistant prostate cancer (mCRPC). Since radiation therapy (RT) can suppress the bone marrow function and immune response, previous studies evaluating sip-T excluded pts who received RT less than or equal to 28 days prior to sip-T therapy. Recent evidence suggests that RT may act synergistically with immunotherapy to enhance and broaden antitumor immune response. Methods: Pts who met standard criteria for sip-T were randomized to receive sip-T alone (Arm A) or sip-T initiated 1 week after completing sensitizing RT to single metastatic site (Arm B). RT was delivered at 300cGy/day to 3000 cGy total. The primary endpoint was the ability to safely combine sip-T preceded by RT and generate sip-T product with adequate immune activation parameters. Secondary endpoints included the measurement of immune responses to prostatic acid phosphatase (PAP) and PA20204 (recombinant fusion protein utilized in the generation of sip-T). Results: 51 pts were enrolled, 2 did not receive any sip-T because of vascular access problems and were excluded. 24 were treated on Arm A, 25 on Arm B. 47/49 pts received all 3 sip-T infusions. Median age was 66 yrs (range 45-90). Sip-T product parameters including: total nucleated cell (TNC) count, antigen presenting cell (APC) count and APC activation were similar in both groups. 2 pts on Arm A demonstrated PSA response. Median progression free survival (PFS) was 3.0 months on Arm A and 4.6 months on Arm B (p = 0.19). Both arms showed similar increases in humoral responses to PA2024 and PAP. IFN-ƴ ELISPOT T-cell activation responses to PA20204 were observed in both arms, but were more robust in the Arm A (p = 0.04). Both arms were well-tolerated, with fatigue as the most common grade 2 adverse event (1 pt in Arm A and 3 pts in Arm B). Conclusions: Sensitizing RT completed 1 week before generation of sip-T did not affect product parameters and the ability to deliver sip-T therapy. RT did not enhance the humoral and cellular responses associated with sip-T therapy. Clinical trial information: NCT01807065.

Current state of continuous ambulatory peritoneal dialysis in Egypt.

Patients with end-stage renal disease (ESRD) continue to increase in number worldwide, especially in developing countries. Although continuous ambulatory peritoneal dialysis (CAPD) has comparable survival advantages as hemodialysis (HD), it is greatly underutilized in many regions worldwide. The prevalence of use of CAPD in Egypt is 0.29/million population in 2017. The aim of this study is to describe the current state and practice of CAPD in Egypt and included 22 adult patients who were treated by CAPD. All the study patients were switched to CAPD after treatment with HD failed due to vascular access problems. Patients were mainly female (68.2 %) with the mean age of 49.77 ± 11.41 years. The average duration on CAPD was 1.76 ± 1.30 years. Hypertension was the main cause of end-stage renal disease (ESRD) constituting 36.4%, followed by diabetes (27.3 %), and toxic nephropathy (4.5%). Of importance is that about 31.8% of patients had ESRD of unknown etiology. The mean weekly Kt/V urea of patients on PD was 1.92 ± 0.18. The mean hemoglobin, serum calcium, phosphorus, parathormone, and albumin levels were 10.27 ± 1.98 g/dL, 8.36 ± 1.19 mg/dL, 5.70 ± 1.35 mg/dL, 541.18 ± 230.12 pg/mL, and 2.98 ± 0.73 g/dL, respectively. There was no significant difference between diabetic and nondiabetic CAPD patients regarding demographic and laboratory data. Our data indicate that there is continuing underutilization of CAPD in Egypt which may be related to nonavailability of CAPD fluid, patient factors (education and motivation), gradual decline of the efficiency of health-care professionals, and lack of a national program to start PD as the first modality for renal replacement therapy. It is advised to start an organized program to make CAPD widespread and encourage local production of PD fluids to reduce the cost of CAPD.

Problem of Vascular Access in Hemodialysis as First Choice Treatment in Senegal

Problem of Vascular Access in Hemodialysis as First Choice Treatment in Senegal

The possibility of renal function recovery in chronic hemodialysis patients should not be overlooked: Single center experience.

Chronic hemodialysis is implemented when irreversible loss of kidney function occurs. Sometimes renal recovery is overlooked. From January 2005 to December 2014, we identified 28 patients hemodialyzed for more than 3 months who had renal replacement therapy discontinued. The group consisted of 17 (57.7%) males and 11 (42.3%) females. Patients were 18-87 years old. Time of hemodialysis ranged from 3 to 97 months. Of note, 14 (50%) patients were referred from local dialysis units for solution of vascular access problems. In 13 (46.2%) patients dialysis was abandoned within the first 6 months, in 5 (17.8%) patients between 6 and 12 months, and in 10 (35.7%) patients beyond 12 months. Estimated dialysis-free survival was 94.4% (SE 0.054) and 82% (SE 0.095) at 12 and 24 months, respectively. All physicians must be aware of possible kidney function improvement. In patients with preserved diuresis fall in periodical urea or creatinine measurements might be a sign of renal recovery.

Novel Bone-Anchored Vascular Access on the Mastoid for Hemodialysis: Concept and Preclinical Trials.

We present the development of a bone-anchored port for the painless long-term hemodialytic treatment of patients with renal failure. This port is implanted behind the ear. The port was developed based on knowledge obtained from long-term experience with implantable hearing devices, which are firmly anchored to the bone behind the ear. This concept of bone anchoring was adapted to the requirements for a vascular access during hemodialysis. The investigational device is comprised of a base plate that is firmly fixed with bone screws to the bone behind the ear (temporal bone). A catheter leads from the base plate valve block through the internal jugular vein and into the right atrium. The valves are opened using a special disposable adapter, without any need to puncture the blood vessels. Between hemodialysis sessions, the port is protected with a disposable cover. Flow rate, leak tightness, and purification were tested on mockups. Preoperative planning and the surgical procedure were verified in 15 anatomical human whole head specimens. Preclinical evaluations demonstrated the technical feasibility and safety of the investigational device. Approximately 1.5 million people are treated with hemodialysis worldwide, and 25% of the overall cost of dialysis therapy results from vascular access problems. New approaches toward enhancing vascular access could potentially reduce the costs and complications of hemodialytic therapy.

Preferred haemodialysis vascular access for diabetic chronic kidney disease patients: a systematic literature review.

Vascular access problems are one of the main concerns in the diabetic end-stage kidney disease (ESKD) population. However, the optimal strategy for the establishment of vascular access in this population remains to be solved. We performed a systematic review in order to clarify the most advisable approach of vascular access planning in diabetic patients with ESKD. MEDLINE, EMBASE and CENTRAL databases were searched for English-language articles without time restriction through focused, high-sensitive search strategies. We included all studies providing outcome data on diabetics starting chronic haemodialysis treatment on the basis of the type of primary placed vascular access. A total of 13 studies comprising over 2,800 participants with diabetes were reviewed in detail and included in the review. We found that diabetic patients using a dialysis catheter apparently experience a higher risk of death and infection compared with patients who successfully achieved and maintained an arteriovenous fistula as dialysis access. The comparison between the use of a graft or an autogenous fistula as dialysis access generated conflicting results. Primary patency rates appeared to be lower in diabetics versus non-diabetics. Our study suggests that diabetic ESKD patients with dialysis catheters incur a higher risk of death in comparison to those who achieve an arteriovenous access. It is however unclear whether this is caused by residual selection bias or by a true advantage of native vascular access.

P2-7-6 - Administration of Chemotherapy Via Median Cubital Vein Without Central Venous Access Port for Colorectal Cancer

Background: Repeated venous punctures are usually required in cancer patients for application of chemotherapy. Central venous catheters and implantable port systems have substantially facilitated the problem of vascular access. Safe and easy-to-handle port systems have become an integral part of daily clinical routine in oncology. However, there are several serious complications associated with central venous ports (CV-ports). With the recent development of capecitabine plus oxaliplatin (XELOX) therapy involving oral administration of drug preparations, etc., implantation of a CV-port can be avoided. The present study was undertaken to evaluate the safety of administration of chemotherapy via median cubital vein without CV port for metastatic colorectal cancer.Methods: The study included 144 patients who received XELOX + bevacizumab (BV) therapy and XELOX therapy for metastatic colorectal cancer without implantation of a CV-port.Results: Eighty-five patients experienced vascular pain, but it was transient. The drip infusion route had to be switched to the opposite side because of vascular pain in only 1 of the 144 patients. No patients required CV-port implantation or postponement of treatment due to adverse events caused by administration of the drug via the peripheral vein. Grade 3 or higher hemotoxicity was noted in 12.5%, and grade 3 or higher nonhematological toxicity was noted in 17.4%.Conclusions: We may be able to perform port-free-chemotherapy via median cubital vein for patients with colorectal cancer. We can avoid the serious complications associated with CV-port.

Subcutaneous implantable cardioverter-defibrillator: Initial experience

BackgroundImplantable cardioverter-defibrillators (ICDs) are important tools in the prevention of sudden death, but implantation requires transvenous access, which is associated with complications. Subcutaneous implantable cardioverter-defibrillators (S-ICDs) may prevent some of these complications. AimTo evaluate the therapeutics and complications associated with S-ICD systems. MethodsS-ICD implantation was planned in 23 patients, for whom the indications were vascular access problems, increased risk of infection or young patients with long predicted follow-up. The population consisted of four patients with ischemic heart disease, three of them on hemodialysis (two with subclavian vein thrombosis), five with left ventricular noncompaction, four with Brugada syndrome, three with arrhythmogenic right ventricular cardiomyopathy, one with transposition of the great vessels, two with dilated cardiomyopathy and four with hypertrophic cardiomyopathy. ResultsS-ICDs were implanted in 21 patients, two having failed to fulfill the initial screening criteria. Mean implantation time was 77 minutes, with no complications. Defibrillation tests were performed, and in one patient the generator had to be repositioned to obtain an acceptable threshold.In a mean follow-up of 14 months, 10 patients had S-ICD shocks, which were appropriate in half of them; one developed infection, one needed early replacement due to loss of telemetry and one patient died of noncardiac cause. ConclusionsS-ICD implantation can be performed by cardiologists with a high success rate. Initial experience appears favorable, but further studies are needed with longer follow-up times to assess the safety and efficacy of this strategy compared to conventional devices.

Cardioversor desfibrilhador implantável subcutâneo – experiência de um centro

BackgroundImplantable cardioverter‐defibrillators (ICDs) are important tools in the prevention of sudden death, but implantation requires transvenous access, which is associated with complications. Subcutaneous implantable cardioverter‐defibrillators (S‐ICDs) may prevent some of these complications. AimTo evaluate the therapeutics and complications associated with S‐ICD systems. MethodsS‐ICD implantation was planned in 23 patients, for whom the indications were vascular access problems, increased risk of infection or young patients with long predicted follow‐up. The population consisted of four patients with ischemic heart disease, three of them on hemodialysis (two with subclavian vein thrombosis), five with left ventricular noncompaction, four with Brugada syndrome, three with arrhythmogenic right ventricular cardiomyopathy, one with transposition of the great vessels, two with dilated cardiomyopathy and four with hypertrophic cardiomyopathy. ResultsS‐ICDs were implanted in 21 patients, two having failed to fulfil the initial screening criteria. Mean implantation time was 77 minutes, with no complications. Defibrillation tests were performed, and in one patient the generator had to be repositioned to obtain an acceptable threshold.In a mean follow‐up of 14 months, 10 patients had S‐ICD shocks, which were appropriate in half of them; one developed infection, one needed early replacement due to loss of telemetry and one patient died of noncardiac cause. ConclusionsS‐ICD implantation can be performed by cardiologists with a high success rate. Initial experience appears favorable, but further studies are needed with longer follow‐up times to assess the safety and efficacy of this strategy compared to conventional devices.

Can femoral dialysis catheter insertion cause a life threatening complication?

Venous catheter (VC) insertion may be necessary for the patients with renal failure facing vascular access problem. Femoral VCs are commonly used for their lower complication rates especially in emergency clinics. The incidence of bleeding associated with VC is reported 0.5-1.6%, however, life threatening hemorrhage and complications requiring surgical intervention are very rare. In this manuscript, we aimed to present a case with hemolytic uremic syndrome complicated with retroperitoneal hematoma after femoral VC insertion. J Clin Exp Invest 2014; 5 (3): 472-474

Postoperative assessment of vascular access.

Vascular access problems lead to increased patient morbidity and mortality. Autologous arteriovenous fistulas (AVFs) are preferred over grafts. An increase in utilization of AVFs results in an increased incidence of early AVF failure and nonmaturation. A thorough evaluation of a new AVF after 4-6 weeks after creation should be considered mandatory. Experienced persons can examine AVF and predict its utility as a dialysis access. Detailed physical examination of the access performed by educated and trained staff can provide, in most cases, adequate information about the main causes for AVF dysfunction in case of nonmaturation or in case of late access complications. Physical examination has been shown to be very accurate in assessing fistula and is not difficult to learn. Doppler ultrasound (DU) is an additional diagnostic method to predict the ultimate maturation of newly created AVFs and is also very useful in further defining problems that have been detected by physical examination. DU also provides additional information that is of the utmost importance for the surgical or interventional treatment.In this review, basic principles of physical examination and of DU examination of early and late AVF/graft complications are shown.

Clinical evaluation of an expert system for arteriovenous fistula assessment.

The monitoring of ionic dialysance in hemodialysis allows early detection of arterio-venous fistula stenosis. One limitation to the practical use of ionic dialysance is that the analysis is very time consuming on a majority of normal cases.The purpose of the study is to evaluate the utility of an expert system reproducing a human analysis and allowing continuous monitoring of the ionic dialysance by helping the physician to focus his or her expertise on the abnormal cases.The method is based on a Bayesian model that analyzes the blood flow rate, the ionic dialysance, and the venous and arterial pressures measured on the extra corporeal circuit.The clinical evaluation was performed on 90 dialysis patients at the hospital dialysis center of Saint Brieux in France with a history of at least four consecutive months of validated recording. The retrospective automated analysis was evaluated in comparison to vascular access problems identified from invasive investigation or treatment. The sensitivity of the automated analysis is 92% with a specificity of 75%.As a conclusion we suggest that this expert system could be used in a continuous vascular access monitoring procedure consisting in a weekly review of the patient population at the dialysis center. The patients with the highest risk score need a further investigation of their historical data and their medical history in order to decide whether or not to perform an invasive intervention.

Administration of chemotherapy via median cubital vein without implantable central venous access port for metastatic colorectal cancer: Port-free chemotherapy.

651 Background: Repeated venous punctures are usually required in cancer patients for application of chemotherapy. Central venous catheters and implantable port systems have substantially facilitated the problem of vascular access. Safe and easy-to-handle port systems have become an integral part of daily clinical routine in oncology. However, there are several serious complications associated with central venous ports (CV-ports). With the recent development of capecitabine plus oxaliplatin (XELOX) therapy involving oral administration of drug preparations, etc., implantation of a CV-port can be avoided. The present study was undertaken to evaluate the safety of administration of chemotherapy via median cubital vein without CV port for metastatic colorectal cancer. Methods: The study included 144 patients who received XELOX + bevacizumab (BV) therapy and XELOX therapy for metastatic colorectal cancer without implantation of a CV-port. Results: Eighty-five patients experienced vascular pain, but it was transient. The drip infusion route had to be switched to the opposite side because of vascular pain in only 1 of the 144 patients. No patients required CV-port implantation or postponement of treatment due to adverse events caused by administration of the drug via the peripheral vein. Grade 3 or higher hemotoxicity was noted in 12.5%, and grade 3 or higher nonhematological toxicity was noted in 17.4%. Conclusions: We may be able to perform port-free-chemotherapy via median cubital vein for patients with colorectal cancer. We can avoid the serious complications associated with CV-port.

Interventional Nephrology

There is increasing awareness of vascular access dysfunction as a significant contributor to the morbidity associated with chronic hemodialysis. Over the last several years, interventional nephrologists, in conjunction with our colleagues in vascular surgery, have led the way in the creation of novel devices that are designed to help solve the vascular access problem. The purpose of this review is to describe novel devices in the precommercial stage of development that have the potential to revolutionize the field of dialysis vascular access. These devices include bioengineered blood vessels, access monitoring technology, and advanced anastomotic connectors.

Monitoring Dialysis Arteriovenous Fistulae: It's in our Hands

Vascular access problems are a daily occurrence in hemodialysis units. Loss of patency of the vascular access limits hemodialysis delivery and may result in underdialysis that leads to increased morbidity and mortality. Despite the known superiority of autogenous fistulae over grafts, autogenous fistulae also suffer from frequent development of stenosis and subsequent thrombosis. International guidelines recommend programmes for detection of stenosis and consequent correction in an attempt to reduce the rate of thrombosis. Physical examination of autogenous fistulae has recently been revisited as an important element in the assessment of stenotic lesions. Prospective observational studies have consistently demonstrated that physical examination performed by trained physicians is an accurate method for the diagnosis of fistula stenosis and, therefore, should be part of all surveillance protocols of the vascular access. However, to optimize hemodialysis access surveillance, hemodialysis practitioners may need to improve their skills in performing physical examination. The purpose of this article is to review the basics and drawbacks of physical examination for dialysis arteriovenous fistulae and to provide the reader with its diagnostic accuracy in the detection of arteriovenous fistula dysfunction, based on current published literature.

Short-term central venous catheter complications in patients with sickle cell disease who undergo apheresis

Patients with sickle cell disease (SCD) are prone to develop thrombosis and infection due to their inflammatory and immune deficiency state. These patients require red cell exchange therapy for treatment or prevention of hemoglobin S associated complications. Owing to vascular access problems, adult patients need central venous catheterization (CVC) for exchange procedures. Procedure related complications have been reported for long-term CVCs in pediatric patients. However, short-term CVC complications in adult patients are not clear. This report represents the results of documented complications of short-term CVCs in patients with SCD who undergo apheresis. A total of 142 non-tunneled catheters with average median diameter of 9F (range 8-16F) were implanted for apheresis. The catheters were mainly inserted through the right internal jugular vein (66.2%). Total days of catheter were 412. Results were reported as a complication rate and event according to 1,000 catheter days and compared to a control group including 37 healthy stem cell donors. In the patient group, 1 (1%) hematoma and 1 (1%) infection were observed for internal jugular vein catheterization (3.7 hemorrhages and 3.7 infections according to 1,000 catheter days), whereas four (8.9%) cases of thrombosis and 1 (2.2%) infection (27 and 6.9 according to 1,000 catheter days) developed in femoral vein. There was a significant difference in terms of thrombosis (P=0.009). In the control group, only individual developed thrombosis in internal jugular vein. Short-term CVC inserted through to the internal jugular vein seems to be safer than femoral vein in patients with SCD.

Skypeビデオ通話による透析患者のバスキュラーアクセス遠隔診療

Skypeビデオ通話による透析患者のバスキュラーアクセス遠隔診療

Análisis entre la recirculación medida por termodilución (BTM®) y la presión venosa dinámica inicial como métodos para la detección de estenosis del acceso vascular protésico

Introducción: Los problemas de acceso vascular suponen la mayor causa de morbilidad y mortalidad en el paciente en hemodiálisis. La estenosis es a su vez la principal causa de disfunción del acceso vascular protésico, y cuando éste problema no se logra detectar a tiempo, puede derivar en trombosis. Existen múltiples procedimientos para la detección de disfunción del acceso vascular desde la exploración física, mediciones de presión y flujo, así como pruebas de imagen no invasivas e invasivas. La Presión Venosa Dinámica inicial, es una herramienta sencilla de seguimiento del acceso vascular. Objetivos: El objetivo del estudio es correlacionar la presión venosa dinámica inicial y la recirculación como métodos de vigilancia del acceso vascular en pacientes en hemodiálisis. Material y métodos: Se evaluaron de forma prospectiva 21 pacientes con prótesis durante 1 año. Se registraron signos clínicos y parámetros de medición objetivos como recirculación por termodilución, presión venosa dinámica inicial con flujo de sangre de 200 ml/min, tiempo de hemostasia, y KT/V por OCM, contrastándose con los hallazgos de las pruebas de imagen. Se realizaron mediciones mensualmente, con un total de 244. Resultados: La prótesis de PTFE representó el 16,6% de los accesos vasculares en nuestra unidad durante el periodo de estudio. La media de edad fue de 63 años con un 57% de mujeres. El tiempo medio de diálisis fue de 225 min con un Kt/V por OCM de 1,44. De los signos clínicos, la mayor incidencia fue presencia de pseudoaneurismas, en un 42,8%. La media de recirculación fue 10,46±2,68% y la presión venosa dinámica inicial 94,51±19,58 mmHg. Se registraron en total 21 eventos: 14 fistulografías+ angioplastia, 4 trombosis con reparación quirúrgica, 2 fistulografías sin necesidad de angioplastia y una trombosis no recuperada. Cuando se compararon las mediciones de recirculación y presión venosa dinámica inicial, con la aparición de eventos, se encontró relación significativa con la presión venosa dinámica inicial (p