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A high-flow access has been defined as one with a flow >1-1.5 l/minute or as one where the access flow is >20% of the cardiac output. Although it may be asymptomatic, it can be associated with cardiopulmonary complications, aneurysms, central vein stenosis and the distal hypoperfusion ischemic syndrome in some patients. The decision for surgical intervention should be made after careful medical optimization especially in patients with high output cardiopulmonary compromise. In this review, we present a summary of current knowledge about the pathophysiology of a high-flow fistula, followed by a concise, comprehensive synopsis of current medical and surgical therapy.

The placement of a peritoneal dialysis (PD) catheter by interventionalists demands not only procedural skill but also an ability to decipher real-time ultrasonographic and fluoroscopic images. In this article, we discuss how imaging assists in PD placement and recognition of complications. To aid this endeavor, we have provided images and video clips that should assist interventionalists. Compared with the fluoroscopic technique, peritoneoscopic PD catheter placement provides direct visual imaging to also aid placement of the initial trocar and the peritoneal catheter.

Stent strut protrusion through the skin is a rare and a potentially dangerous complication from the cannulation of stents placed within arterio-venous fistulas and grafts. Such cases are usually managed surgically. We present a case wherein strut penetration of an arterio-venous fistula was noted at the distal (uncovered) end of a Fluency Plus(®) tracheo bronchial stent graft. After analyzing the various reasons why this may have happened, a nonsurgical approach was taken to preserve the access and manage strut protrusion.

The general and interventional nephrologist may occasionally encounter a situation where the patient may state that he/she has an allergy to lidocaine or heparin. Heparin hypersensitivity is usually either a delayed type hypersensitivity reaction or an immune-mediated thrombocytopenia. While a number of alternative drugs are available, many of them are subject to local availability, food and drug administration indications, and the patient's hepatic and renal function. Many of these drugs do not have antidotes in case of bleeding. Lidocaine hypersensitivity is usually a delayed type reaction, although adverse reactions, which are much more common, are wrongly labeled as an allergy. 1% diphenhydramine and benzyl alcohol may be used as alternatives.

The use of stents has become common practice in various interventional fields. The purpose of this article is to provide the interventionalist with an understanding of the basic structure stent. We describe the etymology, the classification and describe various terms used by engineers as they strive to develop that "ideal" stent. We also describe the fabrication process briefly and finally elaborate on the characteristic "build and cut" of some commonly used stents.

Distal artery embolization is a well-known complication after mechanical thrombectomy, manifesting as limb ischemia. We describe a case of ischemia that developed after mechanical thrombectomy and stent placement in the venous anastomosis of a brachio- basilic arterio-venous graft. Subsequent investigations revealed that the stent had extrinsically compressed the adjacent brachial artery. Although balloon angioplasty of the artery initially restored flow, the patient needed surgical removal of the graft and stent to prevent persistent ischemia.

Nonmaturing or dysfunctional hemodialysis fistulas are often repaired with interposition grafts placed either within the fistula (fistula-to-fistula configuration), or connected to another vein (fistula-to-vein configuration). The goal of this study was to compare the survival and usefulness of the composite accesses thus created, which we call “graftulas,” with upperarm grafts. This was a retrospective study wherein we determined the survival and thrombosis rates of graftulas (n = 24) and upper arm grafts (n = 31) placed 1/1/07 through 12/31/09 and followed through 11/30/10. Graftulas resembled grafts as most (96%) were successfully cannulated in 65 ± 43 days. Survival of graftulas was also similar to grafts (58%, 47%, and 32% vs. 56%, 47%, and 39% at 1, 2, and 3 years respectively, p = 0.60). However, graftulas had a lower thrombosis rate than grafts (0.5 vs. 1.2 per patient year, p = 0.04), and in the fistula-to-fistula configuration, a 2-year thrombosis-free survival of 78%. Total survival of the access site (fistula + graftula) was 92%, 73%, and 42% at 1, 3, and 5 years, respectively. Graftulas possess certain beneficial properties of fistulas and grafts that allows for continued use of the original access site.

Balloon rupture during angioplasty is an uncommon event. The ruptured balloon usually is removed through its introducer sheath without any problems. However, there may be occasions when a ruptured balloon cannot be withdrawn from an access. We describe a simple technique that can be used to extricate a stuck ruptured angioplasty balloon.

Use of long-term dialysis catheters (e.g., tunneled dialysis catheters) predisposes patients to complications. While catheter-related bacteremia is one of the commonest encountered complication, there are a series of rare complications, namely catheter adherence to the vessel wall, catheter fracture, and vessel perforation, that can occur. This article attempts to discuss such complications with emphasis on potential risk factors, clinical presentations, and management options.

Thrombectomy of a clotted upper arm access may be complicated by brachial artery embolization. A number of techniques have been described to relieve the embolization that may not always be successful. Backbleeding is one such technique. We describe a minimal modification that makes backbleeding more effective.

The use of stents has become common practice in various interventional fields. The purpose of this article is to provide the interventionalist with an understanding of the basic structure stent. We describe the etymology, the classification and describe various terms used by engineers as they strive to develop that "ideal" stent. We also describe the fabrication process briefly and finally elaborate on the characteristic "build and cut" of some commonly used stents.

Distal artery embolization is a well-known complication after mechanical thrombectomy, manifesting as limb ischemia. We describe a case of ischemia that developed after mechanical thrombectomy and stent placement in the venous anastomosis of a brachio- basilic arterio-venous graft. Subsequent investigations revealed that the stent had extrinsically compressed the adjacent brachial artery. Although balloon angioplasty of the artery initially restored flow, the patient needed surgical removal of the graft and stent to prevent persistent ischemia.

Nonmaturing or dysfunctional hemodialysis fistulas are often repaired with interposition grafts placed either within the fistula (fistula-to-fistula configuration), or connected to another vein (fistula-to-vein configuration). The goal of this study was to compare the survival and usefulness of the composite accesses thus created, which we call "graftulas," with upperarm grafts. This was a retrospective study wherein we determined the survival and thrombosis rates of graftulas (n=24) and upper arm grafts (n=31) placed 1/1/07 through 12/31/09 and followed through 11/30/10. Graftulas resembled grafts as most (96%) were successfully cannulated in 65 ± 43 days. Survival of graftulas was also similar to grafts (58%, 47%, and 32% vs. 56%, 47%, and 39% at 1, 2, and 3 years respectively, p=0.60). However, graftulas had a lower thrombosis rate than grafts (0.5 vs. 1.2 per patient year, p=0.04), and in the fistula-to-fistula configuration, a 2-year thrombosis-free survival of 78%. Total survival of the access site (fistula+graftula) was 92%, 73%, and 42% at 1, 3, and 5 years, respectively. Graftulas possess certain beneficial properties of fistulas and grafts that allows for continued use of the original access site.