A simple method to create buttonhole cannulation tracks in a busy hemodialysis unit

The preference for fistulae as the hemodialysis access of choice has led to a significant number of accesses that are less than ideal for cannulation. Buttonhole cannulation is ideal for such accesses, but the technique for creation provides major challenges. In 12 patients, buttonhole tunnel tracks were created by leaving the polyurethane catheter of a Clampcath^® hemodialysis needle indwelling for 10 days after the initial cannulation. After each dialysis the catheter was flushed, and dressed with an antibacterial ointment and gauze. Dialysis was carried out via the catheter during that time. After day 10, the catheter was removed, the tunnel track covered with an antibacterial dressing and the tunnel track was cannulated with a dull buttonhole needle at the next dialysis. Successful buttonhole accesses were created in 11 patients after 10 days, the 12th patient required a single sharp needle cannulation before using dull needles. During the first 2 weeks of dull needle cannulation both pain experienced on cannulation and the difficulty cannulating the access were significantly less than in the classical buttonhole technique (P<0.01). Complications during the follow-up period (6 months–1.5 years) included difficulty cannulating with a dull needle (22) and antibacterial agent induced contact dermatitis (4). There was no episode of sepsis or tunnel track infection. Initial cannulation of the fistula using a Clampcath^® hemodialysis needle, leaving the polyurethane catheter indwelling for 10 days, is a simple, safe, and effective technique for the creation of buttonhole tunnel tracks.     

The salvage of aneurysmal fistulae utilizing a modified buttonhole cannulation technique and multiple cannulators

We describe the St Michael's Hospital (SMH) modified buttonhole (BH) cannulation technique as a method that offers a solution for fistulae with aneurysmal dilatation due to repetitive cannulation in a restricted area. This is a prospective cohort study of 14 chronic hemodialysis (HD) patients with problematic fistulae (marked aneurysmal formation and thinning of the overlying skin, bleeding during treatment, and prolonged hemostasis post-HD) because of repetitive, localized cannulation. Each patient was followed for 12 months. The protocol was as follows: creation of tunnel tracks by 1 to 3 experienced cannulators per patient, using sharp needles. After the tunnel tracks were established and cannulation was easily achieved with dull needles, additional cannulators were incorporated with the guidance of a mentor. Bleeding from cannulation sites during dialysis ceased within 2 weeks and skin damage resolved within 6 months in all patients. Hemostasis time postdialysis decreased from 24 to 15 min. Cannulation pain scores decreased significantly. Access flows and dynamic venous pressure measurements remained unchanged. No interventions were required to maintain access patency. In 2 cases, the aneurysms became much less evident. Complications included one episode of septic arthritis and one contact dermatitis. A third patient developed acute bacterial endocarditis 9 months following completion of her follow-up. The SMH modified BH cannulation technique can salvage problematic fistulae, prevent further damage, and induce healing of the skin in the areas of repetitive cannulation. This technique can be successfully achieved by multiple cannulators in a busy full-care HD unit.     

Causes and consequences of inflammation on anemia management in hemodialysis patients

Inflammation is common among hemodialysis patients, and evidence is accumulating to suggest that inflammation is a major contributor to morbidity and mortality. Several factors have been suggested as potential causes of inflammation, including infections and the atherosclerosis process, as well as etiologies directly related to kidney disease such as reduced renal function and dialysis. Among several inflammatory biomarkers investigated, serum C-reactive protein (CRP) is the most widely used. In hemodialysis patients, raised CRP levels have been shown to be predictive of cardiovascular events, hospitalization, and all-cause and cardiovascular mortality. Elevated CRP levels may correlate with comorbidities and intercurrent events, all of which may impact the response to erythropoiesis-stimulating agents (ESAs) and lead to higher ESA doses. Most dialysis facilities do not routinely measure CRP, despite recommendations by the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative. Regular measurement of CRP levels may help providers to understand change in ESA dosing and identify patients at risk for cardiovascular events. This review explores the inter-relationships between inflammation, CRP levels, and anemia management in patients receiving hemodialysis.     

Effect of protein-energy malnutrition on erythropoietin requirement in maintenance hemodialysis patients

Possible interactions between inflammatory and nutritional markers and their impact on recombinant human erythropoietin (rHuEPO) hyporesponsiveness are not well understood. We investigated the role of nutritional status in rHuEPO requirement in maintenance hemodialysis (MHD) patients without evidence of inflammation. This cross-sectional study included 88 MHD patients. The associations between required rHuEPO dose and malnutrition-inflammation score (MIS) and several laboratory values known to be related to nutrition and/or inflammation were analyzed. Anthropometric measures including body mass index, triceps skinfold thickness, and midarm circumferences were also measured. Twenty-three patients with serum C-reactive protein levels >10 mg/L were excluded from the analysis. The remaining 65 patients (male/female, 41/24; age 49.1+/-11.4 years; dialysis duration 99.7+/-63.0 months) were studied. These patients had moderate malnutrition and the average MIS was 7.4 (range 3-17). The average weekly dose of administered rHuEPO was 69.1+/-63.1 U/kg. Malnutrition-inflammation score had a positive correlation with the serum concentration of tumor necrosis factor-alpha, whereas it had a negative correlation with anthropometric measures, total iron-binding capacity, prealbumin, phosphorus, creatinine, and triglyceride. According to Pearson's correlation analysis, significant relationships of increased MIS with increased required rHuEPO dose and rHuEPO responsiveness index (EPO divided by hematocrit) were observed (p=0.008, r=-0.326; p=0.017, r=-0.306, respectively). Recombinant human erythropoietin dose requirement is correlated with MIS and adverse nutritional status in MHD patients without evidence of inflammation. Further research should focus on reversing the undergoing microinflammation for a better outcome in dialysis patients.     

Use of the BioHole™ device for the creation of tunnel tracks for buttonhole cannulation of fistula for hemodialysis

Buttonhole cannulation is a method of cannulation of native arteriovenous fistulae traditionally practiced by self‐cannulators. At St Michael's Hospital, this method has been modified to allow its use in problematic fistulae by multiple cannulators. In a busy dialysis unit, the need for a few specific cannulators to establish the tunnel tracks in combination with the variable dialysis schedules creates logistical challenges. A new method of creating tunnel tracks with the use of the BioHole^? device was evaluated. Buttonhole tracks were created in 12 patients using a peg of polycarbonated material with a holder (BioHole^? kit). The peg was inserted into the path left by the hemodialysis sharp needle following the index cannulation. Four of the 12 patients had an alternate access. Buttonhole tracks were successfully created in all the patients, albeit in 2 patients, the initial attempt to establish buttonhole tracks was aborted due to complications and the procedure was rescheduled. Compared with the modified buttonhole technique, pain on cannulation following track creation was significantly less in the BioHole^? group (P<0.001). Ease of cannulation was significantly improved in the BioHole^? group (P<0.05) when compared with that in thrice‐weekly patients using the modified buttonhole technique. Hemostasis postdialysis did not differ between the study groups. The use of the BioHole^? device is effective in the creation of tunnel tracks for buttonhole cannulation, is associated with less pain, and simplifies the logistics of arranging patient and nurses' schedules.     

Cephalic arch stenosis in patients with fistula access for hemodialysis: relationship to diabetes and thrombosis

Numerous studies have identified the fistula as the best access for hemodialysis with fewest complications. The radiocephalic fistula (RCF) is the first access of choice, but often results in poor maturation. Therefore, an increased number of brachiocephalic fistulas (BCF) have been placed. Cephalic arch stenosis (CAS) can occur in patients with fistula access. The current study was done to determine the incidence and associated comorbidities in patients with BCF or RCF who have CAS. A retrospective review of 450 hemodialysis patients in 3 outpatient hemodialysis units between July 1, 2000 and July 1, 2005 (60 months) was preformed. We reviewed demographics, medications, and indications for venograms. Interventional Radiologists reviewed the venograms for evidence of CAS. Radiology reports were screened to determine incidence of thrombosis, treatment with either angioplasty or stent placement and if a complication such as venous rupture occurred. One hundred and twenty-seven patients had fistula access with at least 1 venogram. Of these, 30 were RCF and 97 were BCF. Cephalic arch stenosis occurred in 77% of patients with BCF and in 20% of patients with RCF. Those with diabetes had a lower rate of occurrence than those without (p<0.01). Cephalic arch stenosis led to a high rate of thrombosis (p<0.01). The probability of having multiple radiology procedures was higher with CAS than without (p<0.01). Cephalic arch stenosis is an important problem in hemodialysis patients who have fistula access, and contributes to thrombosis. Diabetes was found to have a negative association with CAS for undefined reasons. Attempts to understand this relationship are important.     

Vascular Access in the Hemodialysis Patient – Personal Experience and Review of the Literature

There is consensus that arteriovenous (AV) fistulae represent the best choice for initial vascular access in patients suffering from chronic renal insufficiency (CRI) or end‐stage renal disease (ESRD) approaching the need of initiating hemodialysis therapy.
However, this is a challenging task in the rapidly growing population of diabetic, aged, and hypertensive patients. The preexisting damage of the vascular anatomy and the high cardiovascular comorbidity hinder construction of a well functioning arteriovenous fistula. Late referrals to the nephrologist delay access surgery and increase the use of temporary and cuffed tunneled catheters with all their potential risks.
Nevertheless, various strategies and tools exist to overcome these problems. Early referral results in venous preservation and early selection of side, site, and type of initial vascular access. Ultrasound findings are essential components of preoperative investigations. Special attention should be paid to the quality of the arteries at each section along the forearm, the elbow region, and the upper arm. Dedicated, meticulous surgery is mandatory. Fistula monitoring and elective revision of the failing AV fistula will result in increasing longevity of the blood access, and will reduce morbidity and costs.     

Use of a "composite" vascular access graft in a young child on hemodialysis

Although arterio-venous fistulae (AVF) are currently considered to be the first choice of permanent vascular access for hemodialysis, there are some patients who are not candidates for fistulae and synthetic grafts provide other options. The Thoratec (Vectra) polyurethane vascular access graft is a new prosthetic graft that may be cannulated within days of insertion due to "self-sealing" properties. However, a tendency for kinking at the suture site due to the strong elasticity of this graft, leading to undesirable complications such as thrombosis, have been reported. We describe a surgical modification of the anastomosis by interposing a segment of expanded polytetrafluoroethylene graft (ePTFE, Venaflo) between the native vessels and the polyurethane graft sections in a pediatric patient. This modification may overcome the kinking complication associated with use of the polyurethane graft and the resulting thrombosis.