Akihiro C. Yamashita

Overview of Regular Dialysis Treatment in Japan as of 31 December 2006

A statistical survey of dialysis patients for the year 2006 was carried out for 4051 medical facilities across Japan, and responses were received from 3985 (98.37%) facilities. There were 264 473 dialysis patients (including 9003 peritoneal dialysis patients) in Japan at the end of 2006, which showed an increase of 6708 (2.6%) from the end of 2005. The number of patients per million population was 2069.9. The crude mortality rate during 2006 was 9.2%. The mean age of the patients who began dialysis (in 2006) was 66.4 years, and the mean age of the entire dialysis population was 64.4 years. The primary renal diseases of the patients who began dialysis were diabetic nephropathy (42.9%), chronic glomerulonephritis (25.6%), and nephrosclerosis (9.4%). Of the 3488 facilities that participated in the survey on the dialysate water quality, 2873 facilities (82.4%) measured the endotoxin concentration in the dialysate; and 1197 facilities (37.1%) out of 3228 measured the bacterial count in the dialysate. The mean hemoglobin concentration in the dialysis population at the end of 2006 was 10.23 ± 1.33 g/dL, which was equal to that at the end of 2005 (10.23 ± 1.37 g/dL). The mean concentration of serum creatinine in 15 853 patients who started dialysis during 2006 was 8.37 ± 3.58 mg/dL. The estimated glomerular filtration rate, which was calculated with formula modified for the Japanese population from the Modification of Diet in Renal Disease (MDRD) Study equation, was 5.46 ± 6.60 mL/min/1.73 m2.

Overview of Regular Dialysis Treatment in Japan (as of 31 December 2005)

Abstract:  A statistical survey conducted at the end of 2005 covered 3985 medical facilities across Japan, and 3940 facilities (98.87%) responded. The dialysis population in Japan at the end of 2005 was 257 765, which showed an increase of 9599 patients (3.87%) from the end of the previous year. The number of patients per million was 2017.6. The crude death rate for one year (from the end of 2004 to the end of 2005) was 9.5%. The mean age of the patients who began dialysis (in 2005) was 66.2 years, and the mean age of the entire dialysis population was 63.9 years. The primary diseases of the patients who began dialysis were diabetic renal disease (42.0%) and chronic glomerulonephritis (27.3%). The mean (±SD) serum ferritin concentration of all the dialysis patients was 191 (±329) ng/mL. The percentages of antihypertensive agents administered to the hemodialysis patients were as follows: calcium‐channel blocker, 50.3%; angiotensin‐converting enzyme inhibitor, 11.5%; and angiotensin II‐receptor blocker, 33.9%. Of the peritoneal dialysis patients, 33.4% used automated peritoneal dialysis devices. Moreover, 7.3% of the peritoneal dialysis patients received dialysis treatment only in the daytime, and 15% received the treatment only at night. Icodextrin solution was used by 37.2% of the peritoneal dialysis patients. The average amount of dialysis solution used by the peritoneal dialysis patients was 7.43 (±2.52) L/day and the average amount of removal fluid was 0.81 (±0.60) L/day. A peritoneal equilibration test was conducted on 67% of the patients, and the mean dialysate to plasma creatinine ratio was 0.65 (±0.13). The annual incidence of peritonitis in the peritoneal dialysis patients was 19.7%. Of the 126 040 patients who responded to the inquiry of the therapeutic situation of peritoneal dialysis, 676 (0.7%) had a history of encapsulated peritoneal sclerosis and 66 (0.1%) were treated for encapsulated peritoneal sclerosis. The mean life expectancy of the dialysis population in 2003 was calculated according to sex and age. Results showed that the mean life expectancy of the dialysis population was approximately 40–60% of that of the general population of the same sex and age.

Evaluation of solute penetration across the polysulfone membrane with vitamin E coating.

Vitamin E (vit E) is coated on polysulfone (PS) dialysis membrane for antioxidative purpose. The membrane, however, has not yet been evaluated from the mass transfer point of view. We investigated this PS membrane with and without vit E coating in vitro ultrafiltration experiments to identify whether or not the coating influences the mass transfer. Dialyzers that included PS membrane with and without vit E coating were investigated. Aqueous test solution of various solutes including vitamin B12 (VB12, MW1355), chymotrypsin (chymo, MW25000), and albumin (alb, MW66000) was prepared, and normal ultrafiltration experiments were performed at 310 K. Reverse ultrafiltration experiments in which test solution was filtered from outside to inside the hollow fiber were also performed. Sieving coefficients (SC) were computed for evaluation. SC for VB12 was the same regardless of vit E coating; however, chymo was 0.82 ± 0.01 and 0.86 ± 0.01, respectively, for the membrane with and without vit E. Thus, it would be understood that vit E coating reduces the pore size of the membrane, resulting the reduced transport of larger solutes. Like other PS membrane, SC for alb was decreased over time regardless of vit E coating. More importantly, although the steady‐state SC for alb was almost identical in two membranes, PS without vit E showed much greater decrease for the first 2 h, while that with vit E showed very little decrease over time, which suggested the reduced fouling effect due to vit E coating. All the SC values found in reverse ultrafiltration were higher than those found in normal ultrafiltration; moreover, the degree of increase with chymo was approximately 5%, whereas that with alb was approximately 430%, which may be explained by a new model in which wedge effect is taken into consideration for the membrane transport. Vit E coating not only has antioxidative effect but also reduces the fouling that is usually caused by various proteins.

Present status of renal replacement therapy at 2015 in Asian countries (Myanmar, Vietnam, Thailand, China, and Japan)

Currently, the Asian region is showing marked population growth and economic progress. In developing countries in Asia, rapid demands for dialysis therapy which have the same standard as those delivered in developed countries have arisen. The end stage renal disease (ESRD) patients have been increasing in these countries, but every country has its own barriers to promote better dialysis due to several reasons as the financial, educational, historical matters and so on. However, they have overcome these problems step by step.The Japanese Society for Dialysis Therapy (JSDT) has started to make efforts to promote exchanges in the region, and increase the standard of dialysis therapy in each country. Based on the information obtained in this symposium, the committee is planning to prepare effective programs for young physicians and paramedics in developing countries.This report is the Review Article by the Committee of International Communication for Academic Research of JSDT. The presentation associated this article was opened at the 61st Annual Meeting of the Japanese Society for Dialysis Therapy held on June 26, 2015 (FRI), Yokohama City, Japan.

Optimal drainage cannula position in dual cannulation for veno-venous extracorporeal membrane oxygenation.

Introduction: Recently, the use of veno-venous extracorporeal membrane oxygenation for adult patients with severe acute respiratory failure has increased. We previously investigated the optimal return cannula position; however, the optimal drainage cannula position has not yet been fully clarified. The aim of this study was to investigate the optimal drainage cannula position. Methods: Veno-venous extracorporeal membrane oxygenation was performed in four adult goats (mean body weight 59.6 ± 0.6 kg). The position of the drainage cannula was varied among the right atrium, the upper inferior vena cava, and the lower inferior vena cava, whereas the position of the return cannula was fixed in the superior vena cava. The recirculation fraction and arterial oxygen saturation and pressure (SaO2, PaO2) were measured in all drainage cannula positions. Results: In the lower inferior vena cava drainage cannula position, the recirculation fraction was the lowest. In the lower inferior vena cava, upper inferior vena cava, and right atrium drainage cannula positions at 3 L/min, SaO2 and PaO2 after 20 min were 92.9% ± 4.9% and 75.1 ± 26.0 mm Hg, 99.5% ± 0.5% and 113.8 ± 20.9 mm Hg, and 93.8% ± 6.2% and 91.9 ± 17.7 mm Hg, respectively. Conclusion: With respect to blood oxygenation, the optimal position for the drainage cannula was the upper inferior vena cava. These findings suggested that blood from the superior vena cava, inferior vena cava, and hepatic vein was most efficiently drained in the upper inferior vena cava cannula position.

Verification of physicochemical structures of dialysis membrane using reversal dialysis technique

Objective: Solute removal performance of the dialyzer is closely related to physicochemical structures of the membrane. The objective of this study is to devise a new in vitro evaluation technique to directly correlate the physicochemical structures of the membrane to the dialysis performance.