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.

Development of vitamin E-modified polysulfone membrane dialyzers.

Oxygen radicals have recently been attracting close attention because of their involvement in tissue damage and their close relationship to various clinical conditions. It has been suggested that hemodialysis increases oxidative stress, triggering the development of complications such as atherosclerosis and dialysis-related amyloidosis. We recently developed a dialyzer containing a highly functional polysulfone membrane on which vitamin E had been bonded (PS-ViE). The present study was undertaken to evaluate the biocompatibility of this membrane and to conduct other experiments on the membrane in vitro. Human blood was dialyzed with minidialyzers (300-600 cm(2) membrane area) made of PS-ViE, cellulose, or untreated polusulfone (PS), and the effects of the dialyzers on complements (C3a, C4a, and C5a), cytokines (IL-1beta and IL-8), and granulocyte elastase as well as their anti-oxidative activity were investigated (n = 6). The effect of PS-ViE on complement activation and its effects on cytokines were comparable to those of PS membrane, whereas granulocyte elastase following dialysis with the PS-ViE membrane tended to be lower than that seen with PS membrane. The effects of PS-ViE-induced methemoglobin, lipid peroxide, and oxygen radicals were significantly less than those of PS membrane, indicating the antioxidative activity of PS-ViE. Vitamin E-modified polysulfone membrane dialyzers were found to have favorable effects on the immune system and to express antithrombotic and antioxidative effects.