View clinical trials related to Arteriovenous Fistula.
Filter by:Hemodialysis (HD) vascular access dysfunction is a huge clinical problem which results in significant morbidity amongst patients with End Stage Renal Disease (ESRD), causing a severe economic burden on any health care system. Native arteriovenous fistula (AVF) is the preferred form of permanent dialysis access since it is associated with the best long term outcome as compared to other forms of dialysis access. Despite the clinical benefits, many patients on HD do not have AVF as there dialysis access. One of the reasons for low AVF rates is early fistula failure (EFF). The two most important causes for EFF amenable to intervention are stenosis anywhere in the circuit and/or presence of accessory vein (av). Although management of stenosis is well established with relatively clear guidelines, the management of av lacks clear scientific approach. In a recent study researchers recommended a hemodialysis arteriovenous flow quantification-diameter (HAQ) criteria for accessory vein obliteration. The purpose of this controlled, blinded, prospective trial is to assess the clinical utility of the HAQ criteria as compared to current recommendations for av obliteration.
Hemodialysis (HD) vascular access dysfunction is a huge clinical problem which results in significant clinical morbidity in patients with End Stage Renal Disease (ESRD), causing a severe economic burden on any health care system. Arteriovenous (A-V) dialysis accesses are the preferred form of permanent dialysis access as compared to central venous catheters (CVC) . One of the reasons for CVC use is poor long term patency rates of A-V access. Arteriovenous Grafts (AVG) have a primary patency rates of just under 50% at 12 months and around 33% at 18 months. Native arteriovenous fistula (AVF) are slightly better with primary patency rates of around 60 percent at one year and 51 percent at 2 years. The most common cause for AVF and AVG dysfunction is stenosis development due to neointimal hyperplasia (NIH) within the circuit leading to access thrombosis. Percutaneous transluminal angioplasty (PTA) is the current standard of treatment for these lesions. Despite being the treatment of choice for these lesions patency rates after PTA continue to be dismal. One of the problems with poor long term outcomes after successful intervention is how you assess immediate intervention success. Successful angioplasty is defined by Dialysis Outcome Quality Initiative (DOQI) guidelines as one where only less than 30% residual stenosis remains at the end of intervention. Unfortunately angiographic images post angioplasty correlate poorly with improvement of access flows through the arteriovenous circuit. There are two main problems with these practice standards. First, they are based on a 2-dimensional angiographic view of the lesion which may be misleading. Secondly, this assessment of recoil is very subjective and not base on objective data. Access flow monitoring can now be performed intra-procedurally with thermal dilution technique. Its benefit was shown in a small pilot study. To date there have not been any randomized controlled trials to assess the benefit of such an approach where intervention is based on improvements in access flow at the time of intervention. We hypothesize that such an approach will improve outcomes after interventions related to access dysfunction. This may also identify the right scenarios in which stent placement may benefit thus improving outcomes after stent placement as well.
The investigators designed a prospective randomized study to compare the conventionally used sedative drug propofol with a latest alternative dexmedetomidine (DEX), in patients with end-stage renal disease undergoing arteriovenous fistula (AVF) surgery.
The purpose of this research study is to determine whether two different types of forearm exercise, performed before fistula creation surgery, can improve surgery success and fistula maturation.
Arteriovenous fistulae are artificial connections between the artery and vein in the arm which allow needles to be inserted for haemodialysising patients wit kidney failure. Occasionally severe debilitating pain can arise from these fistulae for which no cause can be found. Such pain can be very difficult to treat. Many commonly used used painkillers are known to cause significant side effects in patients with renal failure (drowsiness, confusion etc. Qutenza (topical capsaicin 8%) is a new treatment made from chilli peppers which is applied to the skin as a patch and works directly at the nerve endings in the skin to prevent pain. It therefore should not have the systemic side effects of other drugs. It has been demonstrated to be beneficial in other painful conditions for example post-shingles pain and nerve pain from HIV. It has never been used for critical ischaemia before. We propose to investigate the efficacy of Qutenza in treating patients with end stage renal failure and chronic pain from their fistulae (AVF). We will recruit 20 patients with painful AVF and treat them with Qutenza. We will follow them up for 12 weeks and monitor the change in their pain scores.
End stage renal failure (ESRF)describes an irreversible loss in renal function. The majority of these patients will opt for haemodialysis (HD)as their chosen method of renal replacement therapy (RRT). Arteriovenous fistulae (AVF) are the optimal method of achieving vascular access to permit HD. AVF are created with a small surgical procdure to join the artery and vein together. Over the next 6- 8weeks after surgery the AVF should grow ("mature") into a vessel suitable for needles to be inserted for dialysis. Unfortunately however, around 24% - 35% of AVF fail at an early stage. Some anaesthetic techniques can influence intraoperative blood flow and venous diameter, factors which are associated with fistula success. There remains no conclusive evidence that any particular anaesthetic technique can significantly influence long term surgical outcome. This study aims to investigate whether a regional, compared to local, anaesthetic technique can affect fistula patency.
The incidence and prevalence of end-stage renal disease (ESRD) in Taiwan are both the highest worldwide from 2001 to 2008. In Taiwan, more than 90% of the ESRD patients are hemodialysis patients. Either arteriovenous fistula (AVF) or arteriovenous graft (AV graft) is essential for the vascular access of these patients. However, frequent AVF stenosis or thrombosis occurs in 10-30% hemodialytic patients, and the rates are even higher, around 30-70%, in those who has a past history of AVF/AV graft stenosis. Therefore, early detection of AVF stenosis is essential in caring for these hemodialysis patients in terms of medical economics and psychological impact. Unfortunately, angiographic study is expensive and invasive and needs contrast medium injection. The diagnostic accuracy of color duplex ultrasound in AVF stenosis remains satisfactory, but it is not always available when decreased AVF flow or an acute thrombotic event occurs. Continuous AVF/ AV graft flow monitoring by patient himself is a better option in terms of long-term care. Previous study indicated that stethoscope waveform analysis could be used as an alternative to diagnosis of vascular stenosis. Therefore, we aim to investigate AVF/ AV graft stenosis by using the electronic stethoscope (3M Littmann) for AVF sound recording, followed by software analysis by using waveform decomposition, principle component analysis (PCA) and sequential forward selection algorithm [xx]. Our study results will provide a new diagnostic option, which is low cost, non-invasive and self-monitoring, of AVF stenosis in ESRD patients.
Will the technique of adding lidocaine to bupivacaine fasten the onset of bupivacaine alone for infraclavicular brachial plexus block in end-stage renal disease (ESRD) patient?
The purpose of this study is to determine if Effective Extracorporeal Blood Flow(eEBF) has correlation with Access Blood Flow (Qa), when eEBF adjusts with Dynamic Arterial Line Pressure (DALP) in patients with Arteriovenous fistulae in hemodialysis treatment.