Haemodialysis dose is independent of type of surgically-created vascular access

Background: In the United States, the use of polytetraflourotheylene (PTFE) graft compared with native arteriovenous fistula (AVF) for haemodialysis vascular access has been increasing despite a greater than two-fold higher incidence of thrombosis and infection associated with PTFE grafts. Methods: We studied 214 haemodialysis patients with not more than two revisions of their vascular access, to determine whether any relationship exists between the type of haemodialysis vascular access and dialysis dose assessed primarily by urea reduction ratio (per cent reduction in blood urea nitrogen concentration after a dialysis session). Serum albumin concentration was used as a secondary outcome measure of dialysis adequacy. Urea reduction ratio and predialysis serum albumin concentration were measured at onset of study and at 4-week intervals and mean values were calculated for each subject. Results: The 214 patients (118 males, 96 females) included 173 Blacks (81%), 26 Whites (15%), and 15 Hispanics (7%), of mean (±SD) age 55.6±15.5 years. Of these 214 subjects, 111 (52%) had a native AVF, while 103 (48%) had a PTFE graft. Both mean urea reduction ratio (native AVF=69±6.7% vs PTFE graft=70±7.3%; P=0.31), and mean serum albumin concentration (native AVF=4.02±0.39 g/dl vs PTFE graft=4±0.33 g/dl; P=0.59) were equivalent in both groups. Separate multiple logistic regression analyses with type of vascular access as one of the independent variables, found no significant relationship between type of vascular access and either a urea reduction ratio >65% (P=0.67), or a serum albumin concentration >4 g/dl (P=0.89), after adjustment for age of vascular access, access revision, location of access, dialyser urea clearance, length of dialysis treatment, body weight, and age. Conclusion: We conclude that PTFE grafts do not permit delivery of better dialysis than native AVF. The increasing use of PTFE grafts in the United States does not have any clinical justification.     

Timing of first cannulation and vascular access failure in haemodialysis: an analysis of practice patterns at dialysis facilities in the DOPPS.

BACKGROUND: Optimal waiting time before first use of vascular access is not known. METHODS: Two practices-first cannulation time for fistulae and grafts, and blood flow rate-were examined as potential predictors of vascular access failure in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Access failure (defined as time to first failure or first salvage intervention) was modelled using Cox regression. RESULTS: Among 309 haemodialysis facilities, 2730 grafts and 2154 fistulae were studied. For grafts, first cannulation typically occurred within 2-4 weeks at 62% of US, 61% of European and 42% of Japanese facilities. For fistulae, first cannulation occurred <2 months after placement in 36% of US, 79% of European and 98% of Japanese facilities. Overall, the relative risk (RR) of graft failure in Europe was lower compared with the USA (RR = 0.69, P = 0.04). The RR of graft failure (reference group = first cannulation at 2-3 weeks) was 0.84 with first cannulation at <2 weeks (P = 0.11), 0.94 with first cannulation at 3-4 weeks (P = 0.48) and 0.93 with first cannulation at >4 weeks (P = 0.48). The RR of fistula failure was 0.72 with first cannulation at <4 weeks (P = 0.08), 0.91 at 2-3 months (P = 0.43) and 0.87 at >3 months (P = 0.31) (reference group = first cannulation at 1-2 months). Facility median blood flow rate was not a significant predictor of access failure. CONCLUSIONS: Earlier cannulation of a newly placed vascular access at the haemodialysis facility level was not associated with increased risk of vascular access failure. Potential for confounding due to selection bias cannot be excluded, implying the importance of clinical judgement in determining time to first use of vascular access.     

Renal function during erythropoietin therapy for anemia in predialysis chronic renal failure patients

Recombinant human erythropoietin (r-HuEPO) therapy for anemia in chronic renal failure patients could have unfavorable renal effects since reversal of anemia can raise blood pressure and accelerate experimental glomerular injury. Thus, the effects of r-HuEPO on renal and systemic hemodynamics and the progression of renal disease were studied in predialysis chronic renal failure patients. The clearances of inulin and p-aminohippurate, fractional excretions of albumin and immunoglobulin G, cardiac output, plasma renin activity and aldosterone concentration were assessed at baseline, after short-term r-HuEPO (n = 4) or placebo (n = 4) therapy, and after long-term r-HuEPO for all patients (n = 8). In addition, the slope of l/serum creatinine with time was determined before and during continued r-HuEPO therapy. In contrast to placebo therapy, hematocrit increased with r-HuEPO from 32 to 37% after 7.6 +/- 2.7 weeks (mean +/- SD). Antihypertensive drug therapy was increased in 2 patients in each group. Renal function, cardiac output, plasma renin activity and aldosterone did not change significantly in either group. After 18 +/- 9 weeks of therapy for all patients, hematocrit increased from 31 to 39%. Antihypertensive drug therapy was increased in 5 patients and decreased in 1. Renal function decreased while proteinuria tended to increase. Cardiac output, plasma renin activity and aldosterone did not change. During 37 +/- 22 weeks of r-HuEPO therapy, the slope of l/serum creatinine did not worsen in any patient.(ABSTRACT TRUNCATED AT 250 WORDS)     

Haemoglobin level and vascular access survival in haemodialysis patients.

BACKGROUND: A full correction of anaemia in haemodialysis (HD) patients may lead to an increased risk of vascular access (VA) failure. We studied the relationship between haemoglobin (Hb) level and VA survival. METHODS: Incident patients between January 2000 and December 2002 with <1 month on HD were considered. The relative risk (RR) of access failure was evaluated in four different groups of patients divided according to their Hb level (<10, 10-12, 12-13 and >13 g/dl). Other factors possibly influencing VA survival were also considered: age, gender, diabetes, vascular disease, intact parathyroid hormone (iPTH) and treatment with an angiotensin-converting enzyme (ACE) inhibitor, angiotensin receptor blocker (ARB) or recombinant human erythropoeitin therapy. RESULTS: We studied 1254 patients (1057 with autologous fistulae, 75 grafts and 122 permanent catheters at admission). Based on Cox analysis, we found the next statistically significant RR of VA failure to be 2.3 times higher with grafts than with arterio-venous fistulae (AVFs) and 1.8 times higher in AVFs with Hb <10 g/dl than in AVFs of the next Hb group. There was no statistically significant difference in the RR of VA failure between patients with Hb 10-12 g/dl and those with Hb 12-13 g/dl or >13 g/dl. Diabetes (RR: 1.41, P = 0.06), age >65 years (RR: 1.32; P = 0.11) and iPTH (RR: 1.56; P = 0.01) were identified as predictive factors for VA failure; ACE inhibitors or ARB (RR: 0.69; P = 0.03) were found to be protective factors. CONCLUSIONS: In the studied population, the correction of Hb level to >12 g/dl was not associated with a higher incidence of VA thrombosis than in patients with Hb between 10 and 12 g/dl. ACE inhibitors or ARBs were found to be protective factors, and diabetes, age >65 years and iPTH >400 pg/ml were negative predictive factors for VA survival.     

An evaluation of expanded polytetrafluoroethylene (PTFE) loop grafts in the thigh as vascular access for haemodialysis in patients with access problems.

A total of 21 patients with vascular access problems received 22 PTFE loop grafts in the thigh as vascular access for haemodialysis. Eighteen of 22 grafts supported haemodialysis during the patients' lifetime. Actuarial patient survival was 50% at 2 years with a cumulative graft patency in the survivors of 80.5%. Although early thrombosis has been a problem, no graft has been lost from infection. We feel that these results are encouraging enough to recommend the use of PTFE grafts in the thigh of patients with vascular access problems.     

Homocyst(e)ine and vascular access complications in haemodialysis patients: insights into a complex metabolic relationship.

BACKGROUND: As elevated total homocyst(e)ine (tHcy) is associated with increased risk of vascular thrombosis, we hypothesized that the elevated levels of tHcy seen in patients on haemodialysis may be associated with an increased risk of thrombosis of native arteriovenous fistulae (vascular access failure). Our study was designed to investigate the relationship between tHcy and vascular access failure. The relationship between tHcy and mortality was explored as a secondary analysis. METHODS: The study comprised a cross-sectional analysis of 96 haemodialysis patients at a single university-affiliated hospital and a subsequent 9-month prospective follow-up of 88 of the 96 patients. RESULTS: Levels of tHcy (median 30 micromol/l) were elevated. In the initial cross-sectional sample, there was an inverse relationship between tHcy and history of vascular access failure which was not observed in the prospective study. Variables influencing the risk of vascular access failure in the prospective study included history of previous vascular access failure (RR=2.93, P=0.03), use of antiplatelet agents (RR=0.13, P=0.01), increased urea reduction ratio (RR=0.55 for a 5% increase, P=0.01) and increased weight (RR=0.61 for a 10 kg increase, P=0.02). Secondary analysis showed an unexpected inverse relationship between tHcy and mortality (RR=0.033 for 1 log increase in tHcy, P=0.006), such that the lower levels of tHcy were associated with an increased risk of death in short-term follow-up. CONCLUSION: We did not demonstrate a relationship between tHcy and risk of vascular access failure. Patients with the lowest levels of tHcy appeared to be at increased risk of death in this short-term follow-up. The relationship of tHcy to vascular access complications and death in haemodialysis patients appears complex and requires further study.     

PTFE Grafts Versus Tunneled Cuffed Catheters for Hemodialysis: Which Is the Second Choice When Arteriovenous Fistula Is Not Feasible?

Vascular access‐related complications are still one of the leading causes of morbidity in hemodialysis patients. The aim of this study was to compare polytetrafluoroethylene (PTFE) grafts versus tunneled cuffed permanent catheters (TCCs) in terms of vascular access and patients' survival. An observational study was carried out with a 2‐year follow‐up. Eighty‐seven chronic hemodialysis patients were enrolled: 31 with a PTFE graft as vascular access for hemodialysis versus 56 with a TCC. Patients' mean age was 63.8 ± 14.6 (grafts) versus 73.5 ± 11.3 years (TCCs), P = 0.001. Significantly more patients with TCC had atrial fibrillation than patients with grafts (30.3% versus 6.5%, P = 0.01). In an unadjusted Kaplan–Meier analysis, median TCC survival at 24 months was 5.4 months longer than that of PTFE grafts but not significantly (log‐rank test = 1.3, P = ns). In a Cox regression analysis adjusted for age, gender, number of previous vascular accesses, diabetes, atrial fibrillation, smoking, and any complication, this lack of significant difference in survival of the vascular access between TCC and PTFE groups was confirmed and diabetes proved to be an independent risk factor for the survival of both vascular accesses considered (P = 0.02). In an unadjusted Kaplan–Meier analysis, a higher mortality was found in the TCC group than in the PTFE group at 24 months (log‐rank test = 10.07, P < 0.01). The adjusted Cox regression analysis showed that patients with TCC had a 3.2 times higher risk of death than patients with PTFE grafts. When an arteriovenous fistula (AVF) is not possible, PTFE grafts can be considered the vascular access of second choice, whereas TCCs can be used when an AVF or PTFE graft are not feasible or as a bridge to AVF or PTFE graft creation.     

The impact of hypoalbuminemia in kidney-pancreas transplant recipients.

BACKGROUND: Hypoalbuminemia is associated with poorer outcomes in renal transplantation. Diabetes can compound hypoalbuminemia's detrimental effects. Kidney-pancreas transplantation alters the diabetic milieu; yet, some patients continue to be hypoalbuminemic. METHODS: We retrospectively analyzed 232 patients who underwent simultaneous kidney-pancreas transplantation (SPK) between 1993 and 1997 to determine the incidence and clinical correlates of hypoalbuminemia in SPK recipients. Post-SPK hypoalbuminemia was defined as a serum albumin level < or =3.5 g/dl. Univariate analyses were performed to determine whether post-SPK hypoalbuminemia was associated with pre-SPK variables. The effect of albumin level and hypoalbuminemia on the risk of post-SPK events (cardiac events, cytomegalovirus [CMV] infection, rejection, readmission, kidney and pancreas graft failure, and death) was examined with a Cox proportional hazards model. RESULTS: The study population consisted of 149 men and 83 women. Average follow-up was 2.0+/-1.3 years. Hypoalbuminemia (serum albumin level < or =3.5 g/dL) was most common early after SPK (3 months: 44% of evaluable patients were hypoalbuminemic; 12 months: 15.3%; 36 months: 8.3%). Acute rejection episodes and readmission were the most common adverse events after SPK transplantation. There were 24 episodes of renal allograft loss and only 5 cardiac events. Ten SPK recipients died during the study time period. SPK-related hypoalbuminemia was associated with an increased risk for CMV infection (risk ratio [RR] 2.5; P<0.02), renal graft failure (RR 2.41; P=0.05), pancreas graft failure (RR 3.66; P=0.01), and a trend toward an increased risk for death (RR 2.8; P=0.19). CONCLUSIONS: Post-SPK hypoalbuminemia resolves over time in many patients. Persistent post-SPK hypoalbuminemia is associated with an increased risk for CMV infection, graft loss, and a trend toward decreased survival. Efforts to improve nutrition, as it may affect hypoalbuminemia in SPK recipients, may be one strategy for improving SPK outcomes.     

Correction of anaemia of chronic renal failure with recombinant human erythropoietin: safety and efficacy of one year's treatment in a European multicentre study of 150 haemodialysis-dependent patients

One hundred and fifty patients undergoing regular haemodialysis for end-stage renal failure entered a trial of treatment for anaemia with recombinant human erythropoietin (r-HuEPO). At data cut-off 37 patients (24.6%) had dropped out for various reasons; most of them (n = 22) discontinued because of kidney transplantation (after 3-17 months of treatment). The initial dose was 24 U/kg i.v. thrice weekly, with subsequent dose escalations after a minimum of 2 weeks if the haemoglobin (Hb) was less than 10% above the pretreatment baseline. One hundred and forty-three patients who were eligible for efficacy analysis achieved an Hb increase of greater than or equal to 2 g/dl, and all 139 patients eligible for 'full response' analysis (Hb between 10 and 12 g/dl) were dose titrated to reach this arbitrarily defined optimal range. Patients' response to r-HuEPO treatment was independent of age, weight, nephric state or duration of dialysis treatment. To maintain the Hb within the range of 10-12 g/dl during 1 year's treatment (n = 96) a median weekly r-HuEPO dose of 200 U/kg (range 150-300) divided into one, two, or three administrations appeared to be adequate. This maintenance dose depends slightly on the patient's baseline Hb. The study provides evidence that long-term treatment with r-HuEPO is safe. In 48 patients (of whom 12 had no history of hypertension) elevation of blood pressure required additional treatment, which was effective in all but one who was withdrawn from the study. Four patients had seizures and one suffered hypertensive encephalopathy without convulsions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Role of type of vascular access in erythropoietin and intravenous iron requirements in haemodialysis.

BACKGROUND: Recent data have suggested the existence of a relationship between the use of synthetic vascular accesses and increased erythropoietin (Epo) requirements. The present study aimed to evaluate the possible role of the type of vascular access in both Epo and intravenous (i.v.) iron requirements. METHODS: One-hundred-and-seven individuals without recognized causes of Epo resistance, 62 of them undergoing chronic haemodialysis through native arteriovenous fistulae (AVF) and 45 through PTFE grafts, were retrospectively studied (one-year follow-up). Sixty-nine patients, i.e. all but three with a PTFE graft and 27 with native AVF, were taking anti-platelet agents. Doses of i.v. iron and Epo and laboratory parameters were recorded. RESULTS: Erythropoietin and i.v. iron requirements were higher in the patients dialysed through PTFE grafts compared with those with native AVF (Epo: 103.8+/-58.4 vs 81.0+/-44.5 U/kg/week, P=0.025; i.v. iron: 178.9+/-111 vs. 125.9+/-96 mg/month, P=0.01). On a yearly basis, the difference in Epo dose represented a total of 94582+/-16789 U Epo/patient/year. Moreover, the patients with PTFE grafts received more red blood cell transfusions than patients with native AVF (P=0.021). No differences between laboratory, dialysis kinetics, demographic or comorbidity parameters were found. The type of vascular access was the best predictor of the requirement of > or =150 U/kg/week Epo (P=0.03). Even though the patients who received anti-platelet therapy required more i.v. iron (167.5+/-103.6 vs. 114.5+/-101.4 mg/month, P=0.008) but not more Epo (P=NS), the possibility of an accessory role of anti-platelet agents in the increased Epo requirements with PTFE grafts cannot be ruled out. CONCLUSIONS: The use of a PTFE graft and anti-platelet drugs represents a previously undescribed association related to higher Epo and i.v. iron requirements. The association described herein adds new arguments to the debate concerning the choice of vascular access in chronic haemodialysis patients.     

Significance of platelet activation in vascular access survival of haemodialysis patients.

BACKGROUND: Vascular access failure is the most common cause of morbidity and hospitalization in haemodialysis (HD) patients. Although there are reports that anti-platelet agents can prevent vascular access thrombosis, the relationship between platelet activation and vascular access failure is not clear. The aim of this study was to investigate the role of platelet activation in recurrent vascular access failure. METHODS: The studied subjects were divided into three groups: group I included 23 HD patients with recurrent vascular access failure (native arteriovenous fistula <2 year survival or synthetic arteriovenous graft <1 year survival), group II included 15 HD patients with longer vascular access survival (>5 year survival) and group III included 10 healthy volunteers as controls. The expression of platelet activation markers (CD62P and fibrinogen receptor) and the numbers of platelet-derived microparticles were measured and compared between groups. RESULTS: CD62P-positive platelets were significantly higher in group I than in both group II (7.3+/-3.7 vs 3.5+/-1.3%; P<0.0005) and group III (2.9+/-0.9%; P<0.00005). Fibrinogen receptor-positive (PAC-1-positive) platelets were also significantly higher in group I than in group II (2.2+/-2.1 vs 0.9+/-0.7%; P<0.01) and group III (0.8+/-0.6%; P<0.01). CONCLUSIONS: A higher level of circulating activated platelets is associated with shorter survival of vascular access in HD patients. The higher level of circulating activated platelets may be a predictor of recurrent vascular access failure. The potential advantageous effects of anti-platelet therapy on this patient population warrant further investigation.     

Hypercoagulable states and antithrombotic strategies in recurrent vascular access site thrombosis

Vascular access site thrombosis is a major cause of morbidity in patients receiving hemodialysis. The role of hypercoagulable states in recurrent vascular access site thrombosis remains poorly understood. Data are limited regarding systemic anticoagulation to improve access graft patency, because of concern about hemorrhagic complications. We determined the prevalence of hypercoagulable states and clinical outcome (thrombotic and hemorrhagic) after initiation of antithrombotic therapy in a series of patients with recurrent vascular access site thrombosis. We evaluated 31 patients who had sustained 119 thrombotic events that resulted in vascular access graft failure during the year before evaluation. Sixty-eight percent of patients tested had elevated concentrations of antibody to anticardiolipin or topical bovine thrombin, and 18% of patients tested had heparin-induced antibodies. More than 90% of patients had elevated factor VIII concentration, 62% had elevated fibrinogen concentrations, and 42% had elevated C-reactive protein concentrations. Twenty-nine patients were given antithrombotic therapy: 13 with warfarin sodium, 12 with unfractionated heparin (UFH), and 11 with low molecular weight heparin (LMWH). Seven patients received more than one antithrombotic agent, sequentially. Nineteen patients have had no thrombotic events since beginning antithrombotic therapy (10 with warfarin, 3 with UFH, 6 with LMWH). Mean follow-up was 8.6 months (median, 7 months). Eight patients sustained 10 bleeding complications (5 with warfarin, 3 with UFH, and 2 with LMWH). In conclusion, hypercoagulable states are common in patients with recurrent vascular access site thrombosis. Antithrombotic therapy may increase vascular access graft patency, but is associated with significant risk for hemorrhage. Prospective studies are needed to evaluate the role and safety of antithrombotic agents in improving vascular access graft patency.     

Vascular access outcomes and medication use: a USRDS study

Several medications have been proposed to improve hemodialysis (HD) vascular access outcomes based on potentially favorable anticoagulant, antiplatelet, or pleiotropic properties. The purpose of this study was to evaluate the relationship between medication use and vascular access patency in a group of HD patients. We conducted a historical cohort study of the US Renal Data System Dialysis Mortality and Morbidity Wave II study to identify patients with an arteriovenous fistula (AVF), polytetrafluoroethylene (PTFE) graft, or a permanent catheter for vascular access. Cox regression analysis, adjusted for age, gender, race, history of coronary artery disease, peripheral vascular disease, or coronary artery bypass graft, was used to model the hazard ratio (HR) of permanent vascular access failure. Of the 2001 HD patients in the Wave II study, 901 (45%) were included in the analysis. PTFE graft patency was greater for males (HR, 0.73; 95% CI 0.53-1.00, p = 0.05) and for older individuals (HR, 0.99; 95% CI 0.98-1.00, p = 0.02). Treatment with antiplatelet medications, ticlopidine and dipyridamole (HR, 3.54; 95% CI 1.07-11.76; p = 0.04), or aspirin (HR, 2.49; 95% CI 1.31-4.73; p = 0.005) was associated with significantly worse AVF patency. Antiplatelet agents had a significant negative association with access patency in this cohort. In contrast to other published data, it was difficult to identify any beneficial effect of specific medications on access patency.     

Difficult vascular access in patients with end-stage renal failure

BACKGROUND/AIM: End-stage renal failure patients requiring long-term hemodialysis need a durable vascular access. The arteriovenous fistula (AVF) with its long patency rate and low complication profile is usually the first choice for vascular access creation. However, when superficial veins are not suitable for AVF creation or all have been exhausted as a result of repeated AVF procedures, arteriovenous grafts (AVGs) using expanded polytetraflouroethylene (ePTFE) is an alternative. This study reviewed our experience in using PTFE AVGs for vascular access in patients requiring chronic hemodialysis. MATERIALS AND METHODS: In a prospective study, from September 2002 to October 2004, 21 PTFE AVGs were placed in 21 patients. We evaluated the complications and patency. RESULTS: There were 12 female and nine male patients of mean age 58+/-8.7 years (range=45 to 76 years). Nine patients (43%) had hypertensive nephrosclerosis, 6 (29%) diabetic, 2 (10%) glomerulonephritis, 3 (14%) systemic lupus erythematosis requiring long-term steroids, and 1 (4.7%) unknown cause. The patency rate at 24 months was 85.7%. Complications included graft thrombosis (three; 14.3%), wound infection (three; 14.3%) and graft infection (one; 4.8%). CONCLUSION: ePTFE AVGs offer reasonable patency and serviceability rates as a vascular access modality, but in view of their complication profile, the native vein arteriovenous fistula should continue to be the first choice for vascular access for patients requiring chronic hemodialysis.     

Experience with low dose intravenous and subcutaneous administration of recombinant human erythropoietin

Twelve stable haemodialysis patients were divided into two groups and given recombinant human erythropoietin (r-HuEPO) for 14 weeks either intravenously (i.v.) or subcutaneously (s.c.). Dosage was 25 units/kg either thrice (i.v.) or twice (s.c.) per week for 7 weeks, and then 50 units/kg for a further 7 weeks. Response to s.c. therapy was comparable to i.v. despite a 33% lower weekly dosage, and was significant at both 7 (i.v.: 1.1 +/- 0.3, mean +/- SEM, p = 0.02; s.c.: 0.8 +/- 0.3 g/dl, p = 0.03) and 14 weeks (i.v.: 2.8 +/- 0.5, p = 0.003; s.c.: 2.6 +/- 0.6 g/dl, p = 0.009). A correlation was observed between response to r-HuEPO and initial ferritin levels (r = 0.63, p = 0.04). One patient required an increase in antihypertensive medication and there was one arteriovenous fistula thrombosis. Results suggest that overall s.c. therapy is as effective as i.v. therapy, and that a good response with few side effects can be obtained using relatively low doses of r-HuEPO.     

Nutritional status in type 2 diabetic patients requiring haemodialysis.

BACKGROUND: Type 2 diabetic patients with end-stage renal disease are often overweight (BMI > 24) at the start of dialysis therapy. However, there are very few reports in the literature concerning the nutritional status of these patients after prolonged haemodialysis treatment. Therefore, we compared nutritional parameters in type 2 diabetic patients and age-matched non-diabetic patients after at least 18 months of renal replacement therapy with haemodialysis. METHODS: In a cross-sectional study, we measured BMI, serum albumin, total protein, serum cholesterol and interdialytic weight gain (IWG), and performed a subjective global assessment (SGA) in 14 patients with type 2 diabetes and 16 non-diabetic patients (aged > or = 50 years, haemodialysis therapy > or = 18 months). Protein intake was estimated using the protein catabolic rate (PCR) and Kt/V was calculated to compare the dose of dialysis. RESULTS: BMI was significantly higher in patients with type 2 diabetes (30+/-7 vs 24+/-3, P<0.01). In contrast, the concentration of serum albumin was significantly lower (3180+/-499 mg/dl vs 3576+/-431 mg/dl, P<0.05), but six of the diabetic patients had signs of chronic inflammation. All other nutritional parameters did not differ between the two groups. In addition, there were no significant differences in the intake of protein (PCR 0.93+/-0.19 vs 0.92+/-0.22) and the dose of dialysis (Kt/V 1.13+/-0.19 vs 1.2+/-0.2). CONCLUSION: After > or = 18 months of haemodialysis therapy, the majority of type 2 diabetic patients (9/14) were still overweight (BMI > 24). The nutritional status of diabetic patients was similar to that of age-matched non-diabetic patients on prolonged haemodialysis, but serum albumin levels were significantly lower in diabetics. The lower albumin levels in the diabetic patients may be explained by a state of subclinical chronic inflammation.     

Association of pelvic arterial calcification with arteriovenous thigh graft failure in haemodialysis patients.

BACKGROUND: Arterial calcification is a common problem in patients with chronic kidney disease, and has been associated with adverse clinical outcomes. The goal of the present study was to evaluate whether pelvic artery calcifications are associated with technical failure of arteriovenous thigh grafts in haemodialysis patients. METHODS: From 1 January 1999 to 30 June 2002, thigh grafts were placed in 54 haemodialysis patients who had exhausted all options for permanent vascular access in the upper extremities. Perioperative computed tomography (CT) of the abdomen and pelvis was obtained in 32 of the patients for diagnostic purposes unrelated to vascular access planning. Two radiologists, who were blinded to the graft outcomes, scored the vascular calcifications on CT of the distal aorta, common iliac, external iliac and common femoral arteries on a semi-quantitative 5-point scale. The association between technical graft failure (inability to complete the anastomosis) and the vascular calcification score was analysed. RESULTS: There was a high inter-observer agreement in scoring vascular calcification (kappa = 0.801). Among 26 patients with absent or mild pelvic arterial calcifications (grade 1-2) on CT, none (0%) experienced technical graft failure. In contrast, three of six patients (50%) with moderate to severe calcification (grade 3-5) had technical graft failures (P = 0.004 by Fisher's exact test). The cumulative 1 year graft patency was lower in the group with grade 3-5 calcification (33 vs 81%, P = 0.09). The two groups were similar in age, gender, race, diabetes, duration of dialysis, serum calcium, serum phosphorus and serum parathyroid hormone. CONCLUSION: There is a strong association between pelvic artery calcifications and technical failure of thigh grafts. The presence of moderate to severe vascular calcification is predictive of poor cumulative 1 year graft patency.     

Anemia and renal insufficiency are independent risk factors for death among patients with congestive heart failure admitted to community hospitals: a population-based study

The purpose of this retrospective cohort study was to examine the associations among chronic kidney disease, anemia, and risk of death among patients with heart failure. Retrospective cohort study. Patients with a principal diagnosis of heart failure (ICD9 codes 402.01, 402.11, 402.91, 404.01, 404.11, 404.91, and 428.xx) were included. Chronic kidney disease (CKD) was defined as a serum creatinine >1.4 mg/dl for women and >1.5 mg/dl for men. There were 665 eligible patients in the sample with a mean (SD) age of 75.7 (10.9) yr; 60% were women, 71% were white, and 38% had CKD. On admission, a hematocrit > or =40% was found for 30.3% of the patients; 22.9% had a hematocrit between 36% and 40%, 33.2% between 30% and 35%, and 13.6% had a hematocrit of <30%. The 1-yr death rates among individuals with and without CKD were 44.9% and 31.4%, respectively (relative risk [RR], 1.43; 95% confidence interval [CI], 1.17 to 1.75). The mortality at 1 yr was 31.2% for individuals with a hematocrit > or =40%; 33.8% (RR, 1.08; 95% CI. 0.79 to 1.47) for hematocrit 36 to 39%; 36.7% (RR, 1.17; 95% CI, 0.89 to 1.54) for hematocrit between 30 and 35%; and 50.0% (RR, 1.60; 95% CI, 1.19 to 2.16) for those with a hematocrit <30% (chi(2) for trend was 7.37; P = 0.007). Both hematocrit and serum creatinine were independently associated with increased risk of death during follow-up after controlling for other patient risk factors. In conclusion, CKD and anemia are frequent among older patients with heart failure and are independent predictors of subsequent risk of death.     

Haemodialysis access: a single centre UK Experience

Background: The aim of this study was to determine whether the US National Kidney Foundation Disease Outcome Quality Initiative (K/DOQI) guidelines on haemodialysis access could be achieved and to examine its relevance to patients on dialysis in the UK. Method: A cross sectional study of chronic haemodialysis patients at our institution which involved case note review and measurements of biochemical parameters and dynamic venous pressure (dVP) was performed. Patients with polytetrafluoroethylene (PTFE) grafts were followed prospectively for 18 months. Results: 262 patients were studied - 12%, 43%, 30% and 15% underwent dialysis through dialysis catheters, radial-cephalic fistulae (rAVF), brachial-cephalic fistulae (bAVF) and PTFE grafts respectively. RAVFs, bAVFs and PTFE grafts were the primary access (i.e. the first access created for the patient) in 58%, 35% and 7% respectively. Compared with patients of Caucasian origin, patients of Afro-Caribbean race were 3.80 times (95% confidence limit: 1.51 - 9.53) more likely to have a PTFE graft. Patients with higher 'dry weights' were more likely to have PTFE grafts (p<0.005 by ANOVA). Dialysis adequacy was similar irrespective of type and site of access. We found that 64% of PTFE grafts, 46% of bAVFs and 13% of rAVF had dVPs greater than 150 mmHg, (p<0.0001 by c2). This threshold recommended by DOQI predicted 12 of 13 dysfunctional grafts, but had a positive predictive value of only 50%. Conclusion: We have demonstrated that the K/DOQI guidelines are not only achievable, but that they can be exceeded by a considerable margin. Our data also suggest that the demographic details of patients within a unit will influence the achievable proportion of AVF: PTFE grafts (the proportion of PTFE grafts in Afro-Caribbeans being 3 times higher than in whites). Although a dVP >150 mmHg proved sensitive in predicting future graft dysfunction, it had low specificity.     

Microsurgery in gaining paediatric vascular access for haemodialysis

One hundred and one surgical procedures performed in children for construction and maintenance of vascular accesses for haemodialysis were retrospectively analyzed. There were 86 operations performed to create a new fistula in patients without vascular access or with nonrecoverable failed angioaccess. Fifteen surgical procedures were performed to treat fistula complications. The new fistulas were radiocephalic n = 60 (70%), ulnar-basilic n = 5 (5.8%), antecubital n = 9 (10.3%), and PTFE grafts n = 12 (14%). Microsurgical techniques were used in all cases, including PTFE graft fistulas. A microscope was used in 56 cases (55.4%) and magnifying loupes (× 2.5 magnification) in the rest of the operations. Early-failure rate for radiocephalic fistulas was 10%. Cumulative patency rates in radiocephalic fistulas were 79%, 75%, and 70% at 1, 2, and 5 years, respectively. No statistical differences were found from the cumulative patency curve of 730 radial-cephalic fistulas performed in adults during the same period of time. Radiocephalic fistulas can be constructed in most paediatric cases using microsurgical technique. Elbow fistulas can be the second-choice vascular access, and PTFE grafts can be reserved for children with exhaustion of autologous veins. Brachial-jugular PTFE grafts can be used in cases of subclavian vein stenosis. © 1993 Wiley-Liss Inc.