Novel Capped-Needle Device: A Novel Safety Feature to Eliminate Air Bubbles in Hemodialysis.

INTRODUCTION: Air bubbles in the dialysis circuit are rarely visible after automatic priming; however, they are often visible after the needles are manually connected to the circuit. To prevent this issue, we thought to prime needles with a circuit at automatic priming by the hemodialysis machine. In order to achieve this idea, we designed and manufactured a novel capped needle to connect the needles to the extracorporeal circuit before the automatic priming of the hemodialysis machine. This study investigated the effectiveness of this novel capped needle and compared it with the conventional method for preventing air bubble contamination. METHODS: We tested novel capped needles ten times to evaluate whether the dialysis machine works appropriately and removes air bubbles even with the attached capped needle. Next, we performed 25 trials using the conventional method, in which skilled nurses manually connect the needle. In both methods, we thoroughly counted the air bubbles with our naked eyes. We predicted that the capped needle would leave few bubbles in the circuit. In order to evaluate fewer bubbles, we conducted an additional experiment using a microparticle counter to measure the size and number of the bubbles. RESULTS: We thoroughly searched for air bubbles during each of the ten tests but could not find any bubbles visible to the naked eye. In the conventional method, bubbles were visible in 29 out of 50 cases. The bubble count was significantly lower in the capped-needle method than in the conventional method (p < 0.0001, Pearson's χ2 test). In the additional experiments using the microparticle counter, the average remaining air volume in the extracorporeal circuit was 0.0999 ± 0.2438 nL when the priming was performed using the novel capped needles. CONCLUSION: The novel capped needle eliminated all visible bubbles efficiently and effectively; therefore, it could be a valuable device for hemodialysis treatment. The reduction of air from the dialysis circuit may improve patient prognosis.

Comparison of Body Fluid Volumes Determined by Kinetic Modeling and by Bioimpedance Spectroscopy.

INTRODUCTION: The bioimpedance spectroscopy (BIS) method is used in individual patients requiring body fluid volume measurement. In a hemodialysis facility, however, regular screening of body fluid volumes is also necessary. Such screening, by kinetic modeling, may become possible by calculating distribution volumes of urea and uric acid from regular blood test results. OBJECTIVE: The aim is to compare uric acid distribution volumes with BIS-extracellular volume, urea distribution volume with BIS-total body water, and difference between urea and uric acid distribution volumes with BIS-intracellular volume. METHODS: We reanalyzed stored blood test data of 53 hemodialysis patients obtained together with BIS data of the same patients in our previous study. RESULTS: Significant correlations were found between urea distribution volume and total body water predicted by the BIS method, between uric acid distribution volume and extracellular volume predicted by the BIS method, and between the difference of uric acid distribution volume from urea distribution volume and intracellular volume predicted by the BIS method. In Bland-Altman analysis, comparison of each pair showed no systematic error. The mean difference between each pair was minimal. CONCLUSION: Fluid volumes in different body compartments can be estimated by kinetic modeling as well as by the BIS method.

Predictors of Survival in Chronic Hemodialysis Patients: A 10-Year Longitudinal Follow-Up Analysis.

BACKGROUND: Risk factors of mortality in chronic hemodialysis patients have not yet been sufficiently evaluated. In particular, chronological transits and interactions of the impact of risk factors have rarely been described. METHODS: This study is a post hoc analysis of the participants in the Olme-sartan Clinical Trial in Okinawan Patients under OKIDS (OCTOPUS) study conducted between June 2006 and June 2011. We additionally followed up on the prognosis of the participants until July 31, 2018. Standardized univariable and multivariable Cox regression analyses were used to evaluate the influences of the participants' baseline characteristics on all-cause mortality. We also evaluated chronological changes in the impacts of risk factors, interactions among predictors, and the influence of missing values using sensitivity analyses. RESULTS: Of the 469 original trial participants, 461 participants were evaluated. The median time of follow-up was 10.2 years. A total of 211 (45.8%) participants were deceased. The leading causes of death were infection (n = 72, 34.1%) and cardiovascular disease (n = 66, 31.3%). Univariate and multivariate Cox regression analyses revealed that the impact of diabetes mellitus, history of coronary intervention, and hypoalbuminemia were significant risk factors for mortality during the whole follow-up period. During the early follow-up period (≤3 years), standardized univariate Cox regression analyses revealed that history of amputation (hazard ratio [HR] = 4.61, p < 0.001), lower dry weight, higher cardiothoracic ratio, and lower potassium levels were statistically significant risks. In those who survived for longer than 3 years, a history of stroke (HR = 1.73, p = 0.006), higher systolic blood pressure, lower serum sodium levels, and higher levels of hemoglobin, and serum phosphate were significant risks. We also observed a stable interaction between the impacts of serum phosphate and albumin on all-cause mortality. CONCLUSION: In chronic hemodialysis patients, targets to improve the short-term prognosis and long-term prognosis are not equivalent. Hyperphosphatemia was a significant risk factor for the all-cause mortality among patients with normal serum albumin levels but not among patients with compromised albumin levels.

Access-Related Infections Involving the Buttonhole Technique.

PURPOSE: In this study, we discuss a mechanism of development of access-related Staphylococcus aureus infections in patients on buttonhole (BH) method and logically construct a measure to prevent such infections on the basis of the mechanism. SUMMARY: S. aureus can colonize a BH track. Once S. aureus colonizes a BH track, access-related infections may develop when the equilibrium is upset between the factors of host resistance and a level of bacterial growth in a BH track. Thus, the logically constructed measure to prevent access-related infections are as follows: (1) decolonization of S. aureus from a BH track by applying mupirocin ointment to a BH entry site when a patient has been proven to be a carrier of S. aureus in the track, (2) prevention of bacterial invasion of the BH track by a new method to remove a scab completely, and (3) control of bacterial growth in the BH track by disinfecting the site with diluted povidone-iodine solution (0.1% povidone-iodine solution) before access vessel cannulation.

A New Method That Enables Complete Removal of Scabs at Buttonhole Entry Sites.

BACKGROUND: Scab removal is a time-consuming process and often injures the skin at a buttonhole entry site. Incomplete removal of scabs may cause access-related infection. METHODS: In a new procedure, buttonhole entry sites were treated with a moist healing step after hemodialysis, and then a formed scab was wiped off with a microfiber towel during bathing on the night prior to hemodialysis, which was performed on the following day. In the moist healing step, the entry site was disinfected with a diluted povidone-iodine solution (0.1% povidone-iodine solution). RESULTS: When the buttonhole entry sites of the patients were treated with the new procedure, the scabs had already been removed at the buttonhole entry sites, and the sites were covered with a thin transparent membrane. Histological examination showed the thin membrane was stratum corneum, in which nuclei are still seen in keratinocytes. CONCLUSION: By treating the buttonhole entry sites of patients with the wound moist healing method and then rubbing the sites with a microfiber towel during bathing, scabs can be removed without injuring the skin at the sites in advance.

Deformity of Buttonhole Entry Site Causes Higher Frequency of Vascular Access-Related Infection.

BACKGROUND: Vascular access-related infection is more frequent in patients using the buttonhole method for cannulation of the arteriovenous access for hemodialysis. Deformity of buttonhole entry sites is frequently observed among patients on the buttonhole method for extended periods of time. With deformed buttonhole entry sites, moreover, scabs are often incompletely removed at the time of buttonhole cannulation. METHOD: In 166 patients using the buttonhole method at Hino Clinic in Osaka, Japan as of June 30, 2014, the shapes of buttonhole entry sites were categorized into the following 3 types: flat, depressive deformity, and bulging deformity. A multivariate logistic regression method was used to analyze associations between various data including shapes of buttonhole entry sites and occurrence of access-related infection. We also examined microscopic features of the buttonhole entry site tissue that was removed from a patient who died after 3 years of buttonhole cannulation. RESULTS: For the flat buttonhole entry sites, frequency of access-related infection was 0.12 events/1,000 arteriovenous fistulas as compared to 0.47 events/1,000 arteriovenous fistulas for the entry sites with bulging deformity. Such infection did not occur for the entry sites with depressive deformity. The multivariate logistic regression analysis revealed a significant association between an entry site with bulging deformity and occurrence of access-related infection (odds ratio = 5.369, p = 0.0085). Furthermore, the microscopic section showed granulations beneath the skin at the buttonhole entry site and around the buttonhole tract. CONCLUSION: A significant association was shown between an entry site with bulging deformity and occurrence of access-related infection. The microscopic features of the buttonhole entry site of the patient on the buttonhole method for 3 years suggest that the entity of bulging deformity at the entry site is hypertrophic granulation.

Relationship between Years Elapsed after Initial Buttonhole Cannulation and Frequency of Vascular Access-Related Infections.

BACKGROUND: A reason for the higher frequency of vascular access-related infections in buttonhole cannulation patients remains to be elucidated. If the higher frequency of infections is associated with a factor(s) inherent to the buttonhole method (e.g. existence of a buttonhole track or other factors), the frequency of such infections is expected to increase upon starting buttonhole cannulation. On the other hand, if the higher frequency of the infections is associated with a factor(s) developing secondarily while performing buttonhole cannulation for months or years (e.g. deformity of the buttonhole entry site or other factors), the frequency is expected to rise after a certain time elapses from initiation of buttonhole cannulation. In case the higher frequency of the infections is associated with a factor(s) developing secondarily, the problem may potentially be solved. Thus, the present study is to clarify whether there is 'an infection calm period' after buttonhole cannulation is started. METHODS: The relationship between the time (in years) after buttonhole cannulation is started and frequency of vascular access-related infections was investigated. RESULTS: Frequency of access-related infections was almost constant for 6 years after buttonhole cannulation was started. At the sixth year from initiation of buttonhole cannulation, however, the frequency of access-related infections started rising. CONCLUSION: The rise in frequency of vascular access-related infections in buttonhole cannulation may not be directly associated with inherent factor(s) of the method, but rather a factor(s) developing secondarily while performing buttonhole cannulation over a period of years.

Effects of angiotensin receptor blockade (ARB) on mortality and cardiovascular outcomes in patients with long-term haemodialysis: a randomized controlled trial.

BACKGROUND: Hypertension is a major risk factor for death and cardiovascular disease (CVD) in patients undergoing chronic haemodialysis (HD), but there is uncertainty surrounding the effects of blood pressure (BP) lowering on this high-risk patient group. METHODS: In a multicenter, prospective, randomized, open-label, blinded-endpoint trial, 469 patients with chronic HD and elevated BP (140-199/90-99 mmHg) were assigned to receive the angiotensin receptor blockade (ARB) olmesartan (at a dose of 10-40 mg daily; n = 235) or another treatment that does not include angiotensin receptor blockers and angiotensin-converting enzyme (ACE) inhibitors (n = 234). The primary outcomes were the following: (i) composite of death, nonfatal stroke, nonfatal myocardial infarction and coronary revascularization and (ii) all-cause death. RESULTS: During a mean follow-up of 3.5 years, the mean BP was 0.9/0.0 mmHg lower in the olmesartan group than in the control group (not significant). A total of 68 patients (28.9%) in the olmesartan group and 67 patients (28.6%) in the control group had subsequent primary composite endpoints [hazard ratio (HR) in the olmesartan group 1.00, 95% confidence interval (CI) 0.71-1.40, P = 0.99]. All-cause deaths occurred in 38 patients (16.2%) in the olmesartan group and 39 (16.7%) in the control group (HR, 0.97; 95% CI, 0.62-1.52, P = 0.91). Olmesartan did not alter the risks of serious adverse events. CONCLUSIONS: BP-lowering treatment with an ARB did not significantly lower the risks of major cardiovascular events or death among patients with hypertension on chronic HD. (Cochrane Renal Group Prospective Trial Register number CRG010600030).

Olmesartan clinical trial in Okinawan patients under OKIDS (OCTOPUS) study: design and methods.

BACKGROUND: Guidelines for treatment of hypertension are not available for chronic hemodialysis (HD) population, despite the high mortality rate due to cardiovascular disease (CVD). Survival is much better among hypertensive patients than normal to hypotensive patients. Target levels of blood pressure and the class of antihypertensive drugs have not been examined in prospective studies. METHODS: We designed a prospective randomized controlled study among hypertensive HD patients in Okinawa (Okinawa Dialysis Study, OKIDS). The outcomes will be compared between two treatment regimens, such as (1) renin-angiotensin system (RAS) inhibitor Olmesartan and others, and (2) antihypertensive drugs without RAS inhibitors, in a parallel fashion. The title of the study is Olmesartan Clinical Trial in Okinawan Patients under OKIDS (OCTOPUS). Outcomes are any cause of death and CVD in 3 years in a total of 462 patients. Subjects are age 20-79 years and ambulatory on thrice weekly HD treatment. Eligible patients have resistant hypertension: pre-HD session blood pressure 140/90 mmHg and over for more than 1 month regardless with the use of antihypertensive drugs. Patients treated with RAS drugs are eligible if they continue to be hypertensive for more than 1 month after switching to non-RAS antihypertensive drugs. CONCLUSION: This study provides evidence for the target levels of blood pressure at a pre-HD session and the impact of RAS inhibitors. We also evaluate the usefulness of home blood pressure monitoring in HD patients.

Effect of high fiber density ratio polysulfone dialyzer on protein removal.

BACKGROUND/AIMS: A dialyzer (APS-EX) with a higher hollow fiber density ratio was manufactured using the highest performance polysulfone hollow fiber from Asahi-Kasei Medical. METHODS: We compared the performance of this device in comparison with hemodialysis (HD; APS-S) and hemodiafiltration (HDF) conditions (APS-S, 10 l post-HDF) to evaluate its merit as an internal filtration-enhanced dialyzer. RESULTS: With low molecular weight proteins, APS-EX had a reduction ratio of 74.3% for beta(2)-microglobulin (beta(2)-MG), and 31.0% for alpha(1)-MG. APS-EX had a significant higher removal amount of alpha(1)-MG compared to APS-S (HDF). Significant differences were seen in albumin loss, 4.0 g for APS-EX, 3.0 g for APS-S (HDF), and 0.9 g for APS-S (HD). Using HD mode, APS-EX demonstrated a performance which was more than equivalent to approximately 10 l post-HDF. CONCLUSIONS: The results suggested the possibility that HD equivalent to HDF can be performed safely with the ultrapure dialysate when using APS-EX with internal filtration.

Outcome study of renal biopsy patients in Okinawa, Japan.

Here we report a community-based epidemiologic study of patients who received renal biopsy in Okinawa, Japan between 1967 and 1994. The total number of cases was 2832 (1395 men and 1437 women), and the mean (SD) age at biopsy was 30.0 (10.0) years (range 1.0 to 88.0 years). The most common clinical indications for renal biopsy were proteinuria/hematuria (46.7%), nephrotic syndrome (21.2%), acute glomerulonephritis (10.1%), and systemic lupus erythematosus (7.5%). Patients who received renal biopsy between 1985 and 1994 (N= 1480) were much less likely to have acute glomerulonephritis than patients treated between 1967 and 1984 (N= 1352); the rates of proteinuria/hematuria, renal failure, and diabetes mellitus were slightly higher in the later period. Okinawa patients who began dialysis between 1971 and 2000 (N= 5246) were also studied. Among them, a total of 468 patients (260 men and 208 women) began dialysis after renal biopsy. The cumulative incidence of end-stage renal disease (ESRD) among these patients was 17% in 17 years. Half of these patients developed ESRD in the 5.8 years after renal biopsy. Among the dialysis patients, the biopsy rate was 12.6% in chronic glomerulonephritis, 1.7% in diabetes mellitus, 2.6% in nephrosclerosis, and 52.1% in systemic lupus erythematosus. The diagnoses of primary renal diseases were primarily made clinically. The survival rate after starting dialysis therapy was slightly better in those with than in those without renal biopsy but this finding was not statistically significant (adjusted hazards ratio 0.855, 95% CI 0.711-1.028, P= 0.095). The clinical significance of renal biopsy, other than its provision of histologic evidence, remains to be shown.

A timesaving method to create a fixed puncture route for the buttonhole technique.

BACKGROUND: Up to now, for a successful buttonhole puncture of the vascular access vessel, the fistula should be punctured by the same experienced medical staff for 2-3 months, using sharp needles, until a fixed puncture route is established. METHODS: We developed a timesaving method to create the fixed puncture route for the buttonhole technique. In this method, after the usual haemodialysis (HD), a newly developed thumbtack-shaped polycarbonate peg is thrust toward the access vessel along the same path as the puncture needle that has just been removed. Then, at the beginning of the next HD, the peg is removed and a dull puncture needle is inserted along the track already formed by the peg left in place. These steps are repeated at each HD session for 14 days. Thereafter, the vascular access is achieved at HD sessions by inserting a dull puncture needle through the established puncture route. RESULTS: This buttonhole puncture approach was used in 37 patients for 3 months. While the polycarbonate peg was in place, patients experienced no restrictions in their normal activities of daily living, except during bathing and showering. As for puncture pain, no patient found the pain of the buttonhole technique to be greater than that of the conventional puncture technique. Moreover, no significant bleeding was noted during HD. With this buttonhole puncture approach, only one patient had enough erythema at the puncture site to suggest possible infection. After HD, the time for bleeding to stop was <10 min in 95% of patients. CONCLUSION: This study showed the new timesaving method for creating a buttonhole to be safe and useful.