2005 Japanese Society for Dialysis Therapy guidelines for vascular access construction and repair for chronic hemodialysis.

The guideline committee of Japanese Society for Dialysis Therapy (JSDT), chaired by Dr Ohira, has published an original Japanese guideline, 'Guidelines for Vascular Access Construction and Repair for Chronic Hemodialysis'. The guideline was created mainly because of the existence of numerous factors characteristic of Japanese hemodialysis therapy, which are described in this report, and because we recognized the necessity for standardization in vascular access-related surgeries. This guideline consists of 10 chapters, each of which includes guidelines, explanations or comments and references. The first chapter discusses informed consent of vascular access (VA)-related surgeries, which often resulted in trouble between dialysis staff and patients. The second chapter describes the fundamentals of VA construction and timing of the introduction of hemodialysis with emphasis on the avoidance of catheter indwelling if at all possible. In the third chapter, arteriovenous fistula (AVF) construction and management are discussed from the viewpoint of the most preferable type of VA. The fourth chapter deals with arteriovenous grafts (AVG) which has recently increased in clinical applications. The factors which improve the AVG patency rate are discussed and postoperative management methods are emphasized to avoid possible complications. The fifth chapter deals with short and long-term vascular catheters. It is emphasized that these methods are definitely effective but, at the same time, are apt to be associated with several serious complications and might result in vascular damage. In the sixth chapter, superficialization of an artery is explained. This was originally for emergency use or backup but has been used permanently in 2-3% of Japanese hemodialysis patients. In the seventh chapter, methods for the use of VA are described and the buttonhole method is referred to as one of the options for patients who complain of intense pain at every cannulation. In the eighth chapter, the importance of continuous monitoring is stressed for maintaining appropriate function of VA. As a rule, the internal shunt type VA (AVF, AVG) places a burden on cardiac function. Thus, in the ninth chapter, it is stressed that VA construction, maintenance and repair should always be carried out with consideration of cardiac function which is not constant but variable. The 10th chapter forms one of the cores of this guideline and deals with repair and timing of VA. It is shown how to select a surgical or interventional repair method. In the final 11th chapter, VA types and resultant morbidity and mortality of hemodialysis patients are reviewed.

In preparation for a treatment guideline for suitable vascular access repair in Japan.

In cases of vascular access (VA) for hemodialysis including arteriovenous fistula and arteriovenous graft, venipuncture and hemostasis are usually repeated three times a week. Accordingly, it is assumed that VA vascular disorders are worsened following long-term hemodialysis. In particular, angiostenosis frequently occurs and results in insufficient blood flow or increased venous pressure. Additionally, stenosis is a major cause of VA occlusion. While VA intervention treatment is mainstream for VA stenosis, its major advantage lies in its less invasiveness because it is a percutaneous treatment. A further advantage of this treatment procedure is that the existing VA can be preserved intact. For practical use of VA intervention treatment, however, compliance with the therapeutic indication guideline is required. In K/DOQI of the United States, such a guideline has already been formulated based on evidence and specialist opinion, while the guideline of the European Vascular Access Society is presented in the form of a flowchart. The Japanese Society for Dialysis Therapy is currently preparing a guideline for the construction and maintenance of VA, which introduces the timing and principles of repair of VA in the following six categories: (i) stenosis; (ii) occlusion; (iii) venous hypertension; (iv) steal syndrome; (v) excess blood flow; and (vi) infection. Except for infection, most of the treatments for these events involve VA intervention, thus the need for the guideline for VA intervention treatment is becoming widely recognized.

Sirolimus-eluting stents to abolish intimal hyperplasia and improve flow in porcine arteriovenous grafts: a 4-week follow-up study.

BACKGROUND: The patency of arteriovenous (AV) expanded polytetrafluoroethylene (ePTFE) hemodialysis grafts is severely compromised by intimal hyperplasia (IH) at the venous anastomosis and in the venous outflow tract. We addressed the potential of primary placement of a sirolimus-eluting stent (SES) in a validated porcine model. METHODS AND RESULTS: In 25 pigs, ePTFE AV grafts were created bilaterally between the carotid artery and the jugular vein, whereupon a self-expandable nitinol stent (14 SESs and 11 bare-metal stents) was implanted over the venous anastomosis in 1 of the 2 grafts. After exclusion of technical failures and 1 unilateral occlusion, 16 pigs (9 SESs and 7 bare-metal stents) were included for further analysis. After 28 days, we measured graft flow and performed quantitative angiography. The pigs were then euthanized, and grafts with adjacent vessels were excised for histological analysis. Minimal luminal diameter was substantially larger in the SES group compared with unstented controls (5.9+/-0.2 versus 3.8+/-0.4 mm, respectively, P=0.01), which was accompanied by more prominent graft flow (SES, 1360+/-89 mL/min versus unstented, 861+/-83 mL/min, P=0.05). IH at the venous anastomosis was 77% less in the SES group compared with unstented controls (0.44+/-0.05 versus 1.92+/-0.5 mm2, respectively, P=0.01), whereas IH increased markedly when bare-metal stents were used (5.7+/-1.4 mm2, P=0.05). CONCLUSIONS: SESs in the venous outflow of AV grafts significantly reduce IH and increase vessel diameter and graft flow compared with unstented grafts. These findings suggest that SESs have the potential to improve primary patency of AV grafts in hemodialysis patients.