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Seiji Ohira

Publications and source records attributed to Seiji Ohira.

7 recordsLinked to original sources
PubMed2006

Evaluation of primary failure in native AV-fistulae (early fistula failure).

The most preferable method of vascular access (VA) in maintenance hemodialysis is a native arteriovenous fistula (AVF). Advanced age as well as the rapid increase in underlying diseases such as diabetic nephropathy and nephrosclerosis in these patients also means that the veins and arteries used to establish the AVF have undergone vascular damage, making construction of an AVF more difficult compared with earlier construction. Although there are various conditions under which arterial superficialization or AV graft must be chosen, it remains the rule that the first choice for VA should be AVF whenever possible. To improve postoperative results, it is necessary to reduce malfunctions immediately following surgery. We conducted a survey of 23 dialysis facilities throughout Japan and analyzed data from the past 3 years regarding the functionality of the AVF at initial puncture following construction of 5007 examples of newly constructed AVFs. Upon initial puncture, primary failure (PF) is defined as those cases in which thrombosis or inadequate blood flow occur. Primary failure occurred in 7.6% of the cases in this series, but there was a wide distribution of PF, 0.8% to 23.6%, because of differences in quality among facilities. This difference in PF is probably affected by technical aspects, the main factor being the characteristics of the patient. Survey responses included: (1) vascular damage of the veins and arteries used in creating the AVF and (2) the suitability of the location chosen for construction. In the data collected, many methods were used to repair those primary AFVs in which PF occurred. The salvage rate was 70%. Currently, the most preferable form of VA is AVF adhering to the principle that the proper timing of the choice and construction of AVF should consider the maturation period. To accomplish this, it is vital that vascular mapping be performed preoperatively to construct the AVF. If PF does occur, the cause should be thoroughly investigated and repairs made effectively.

Arteriovenous Shunt, Surgical↗
PubMed2006

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.

Angioplasty, Balloon↗
PubMed2006

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.

Arteriovenous Shunt, Surgical↗
PubMed2004

Encapsulating peritoneal sclerosis in Japan: a prospective, controlled, multicenter study.

BACKGROUND: Encapsulating peritoneal sclerosis (EPS) is recognized as a rare but serious complication of peritoneal dialysis (PD). The aim of this study was to determine the incidence, clinical features, and mortality rate of EPS. METHODS: The authors requested the registration of all PD patients in facilities across Japan where more than 10 patients were treated with PD in this prospective multicenter study. During the 4-year study, the incidence of EPS was observed in the enrolled patients. RESULTS: A total of 1,958 patients who were treated with PD in 57 facilities were followed up from April 1999 through March 2003. EPS occurred in 48 patients, corresponding to an overall incidence of 2.5%. In 33 of the 48 (68.8%) patients, EPS was found after discontinuation of PD. The incidence (and mortality rate) of EPS was 0%, 0.7% (0%), 2.1% (8.3%), 5.9% (28.6%), 5.8% (61.5%), and 17.2% (100%) in patients who had undergone PD for 3, 5, 8, 10, 15, and more than 15 years, respectively. The recovery ratio with total parenteral nutrition, corticosteroids and surgical treatment were 0%, 38.5%, and 58.3%, respectively. Eighteen patients (37.5%) died, 22 (45.8%) recovered, and the status of the other 8 (16.7%) remained unchanged. CONCLUSION: The results of this prospective multicenter study showed that the incidence of EPS was 2.5% within a 4-year observation period and that two thirds of the cases were diagnosed after discontinuation of PD. Because of the current progress in diagnostic technology and therapeutic methodology, it appears that PD can be continued successfully with an acceptable, low risk for EPS for at least 8 years, whereas stricter caution is required for patients receiving PD for longer periods.

Adult↗
PubMed2003

Midpeliq reduces glucose load.

The rate of technique failure is still high in Japan for peritoneal dialysis (PD) patients. Of the dropouts who have been treated with PD for more than 6 years, about half suffer from ultrafiltration failure. That condition is supposedly related to the bioincompatible aspects of conventional acidic PD solutions. In 2001, a neutral-pH, lactate-buffered PD solution with low glucose degradation products (GDPs), Midpeliq (Terumo Corporation, Tokyo, Japan), was developed and began to be used in Japan. After switching 3 patients from conventional acidic PD solution to Midpeliq, we observed that 2 patients could then use lower-glucose PD solutions. Case 1 was a 42-year-old woman with a 10-year history of PD. In February 2001, she was switched from Peritoliq (Terumo) to Midpeliq. One month later, she complained of dizziness, and her blood pressure was found to be down to 96/60 mmHg. Post-change fluid removal increased to 1,481 mL from 1,238 mL (p < 0.02). Before the solution switch, this patient exchanged 4 times daily, using 2 L of 2.5% Peritoliq each time. From 3 months after the solution switch, she exchanged 3 times daily using 2 L of 2.5% Midpeliq and 1 time daily using 2 L of 1.35% Midpeliq. Fluid volume removal stayed almost the same. Case 2 was a 52-year-old man with a 9-year history of PD. In June 2002, he was switched from Dianeal 4 (Baxter Healthcare, Tokyo, Japan) to Midpeliq. After the change, his daily drainage volume increased from approximately 1,500 mL to 2,000 mL. He began to use 2 L of 1.35% Midpeliq 4 times daily instead of 2 L of 1.5% Dianeal 3 times daily and 2 L of 2.5% Dianeal 1 time daily. At 1 month after the solution switch, his drainage volume was still approximately 1,500 mL daily. Our observations suggest that new, neutral-pH PD solutions such as Midpeliq might reduce the glucose load in addition to having low GDPs and fewer toxic effects on the peritoneum.

Adult↗
PubMed2002

Central bronchopleural fistulas closed by bronchoscopic injection of absolute ethanol.

Five consecutive bronchopleural fistulas (BPFs) were successfully treated by injecting absolute ethanol directly into the submucosal layer of the fistula under flexible bronchoscopic observation. No complications occurred as a result of this treatment. Our nonsurgical treatment may be very useful to reduce the costs of and duration of hospitalization and to improve the patient's quality of life. This is the first report of the bronchoscopic closure of BPFs by injecting absolute ethanol, and we would recommend this treatment as a first-line therapy for patients with a postoperative central BPF with an orifice that is < 3 mm in diameter.

Aged↗