Access Failure (access + failure)

Distribution by Scientific Domains


Selected Abstracts


Intima-media thickness of radial artery is associated with early access failure in hemodialysis patients

HEMODIALYSIS INTERNATIONAL, Issue 1 2005
Y.O. Kim
Objective:,We have reported that intimal hyperplasia, which is the pathologic change of the radial artery, is associated with early failure of arteriovenous fistula (AVF) in hemodialysis (HD) patients (Am J Kidney Dis, 41:422,428, 2003). Intima-media thickness (IMT), which represents the whole thickness of arterial wall, can be easily measured by ultrasonography, unlike intima thickness. This study was performed to investigate the impact of IMT of radial artery on early failure of AVF in HD patients. Methods:,Ninety HD patients undergoing radiocephalic AVF operation were included in this study. The AVF was constructed in an end vein,to,side artery fashion at the wrist by one vascular surgeon. During the operation, 10-mm long partial arterial walls were removed with elliptical form for microscopic analysis. Specimens were stained with trichrome and examined by a pathologist blinded to the clinical data. AVF patency was prospectively followed up for 1 year after the operation. Results:,Mean age of the patients was 56 ± 13 years and the number of females was 44 (48.9%). Mean IMT was 430 ± 132 ,m (133,760 ,m). Of the total 90 patients, 31 patients (34.4%) had AVF failure within 1 year after the operation. Mean IMT was higher in the failed group (n = 31) than in patent group (n = 59)(486 ± 130 ,m vs. 330 ± 178 ,m, p = 0.004). Using a threshold of 500 ,m of IMT, AVF patency rate was compared between these two groups using Kaplan-Meier method with log rank test. The AVF patency rate within 1 year after the operation was higher in patients with IMT , 500 ,m (n = 26) than in patients with IMT < 500 ,m (n = 64)(p < 0.001). The patients with IMT , 500 ,m were older and had higher incidence of diabetes mellitus, compared to the patients with IMT < 500 ,m. There was no difference in sex, smoking, hypertension, total cholesterol and albumin levels between the two groups. Conclusion:,Our data suggest that increased intima-media thickness of radial artery is associated with early failure of radiocephalic arteriovenous fistula in hemodialysis patients. [source]


Anticardiolipin antibody and Taiwanese chronic haemodialysis patients with recurrent vascular access thrombosis

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2005
F-R Chuang
Summary Vascular access failure is a major cause of morbidity in chronic haemodialysis (HD) patients. However, some factors (such as homocysteine levels) are known regarding the risk factors predisposing certain HD patients to vascular access thrombosis (VAT). Immunoglobulin-G anticardiolipin antibody (IgG-ACA) is strongly associated with venous and arterial thrombosis in patients with normal renal function. Previous investigations have reported the characteristics of patients with raised IgG-ACA titre and recurrent VAT of HD in Western countries, but few equivalent studies exist for Taiwan. This retrospective study attempts to determine whether raised IgG-ACA titres are associated with an increased risk of recurrent VAT in chronic HD patients. This study enrolled 483 patients undergoing HD. IgG-ACA titre and hepatitis B&C marker were measured for all patients. A history of recurrent (VAT more than one) and/or VAT was elicited by using information from the patient questionnaires and was verified by means of careful inpatient and outpatient chart review. Raised IgG-ACA titres were present in 21.7% (105/483) of patients. In both groups (raised IgG-ACA and normal IgG-ACA), the type of shunt differed significantly (p = 0.029). In predicting for more or one episodes of VAT by using multiple logistic regression with all significant factors, synthetic graft was also a significant factor (p < 0.0001). The 105 raised IgG-ACA titres and 378 normal IgG-ACA titres were associated between chronic HD patients and recurrent VAT (p = 0.034). In predicting for more or one episode of VAT by using multiple logistic regression with all significant factors, raised IgG-ACA titre was a non-significant factor (p = 0.336). The presence of hepatitis C had a higher percentage in group with raised IgG-ACA titres of HD patients (p = 0.042). In predicting for more or one episode of VAT by using multiple logistic regression with all significant factors, the presence of hepatitis C was also a significant factor (p = 0.022). In conclusion, the prevalence of raised IgG-ACA titres was 21.7% among HD patients. There was a weak association between raised IgG-ACA titre and recurrent VAT and this finding may be the consequence of pathogenetic role of raised IgG-ACA titres in the development of VAT status for chronic HD patients. The presence of hepatitis C was a cofactor. [source]


A 5-year audit of haemodialysis access

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2005
J. A. Akoh
Summary This is a review of our experience with vascular access procedures over a 5-year period at Derriford Hospital, Plymouth, UK. The aims of the study were to examine the outcome of vascular access procedures and factors influencing access survival. Between April 1995 and March 2000, 151 patients who underwent 221 vascular access procedures were studied. Of these, 136 had autogenous arteriovenous fistulae, whereas 85 had prosthetic AV grafts (41% in the thigh). The overall primary failure rate was 21% whereas the 1- and 5-year cumulative access survival rates were 60 and 41%, respectively. Thigh grafts have a mean survival of 36 months compared with 32 months for prosthetic upper limb and 43 months for autogenous fistulae. Age, diabetes and predialysis status did not significantly influence access survival. Thrombosis was responsible for access failure in 62 cases (28%). Avoiding subclavian vein canulation and performing vessel mapping prior to access placement should reduce the risk of access failure due to outflow obstruction. [source]


Predicting vascular access failure: A collective review

NEPHROLOGY, Issue 4 2002
Kevan R POLKINGHORNE
SUMMARY: The maintenance of vascular access for haemodialysis contributes a large burden of morbidity and cost to any dialysis unit. Identifying vascular access at risk of thrombosis is an evolving and important aspect to the management of any haemodialysis patient. Haemodynamic profiles of native fistulas and arteriovenous grafts differ significantly, and, as such, the sensitivity of the specific monitoring techniques to detect dysfunction varies depending on access type. Multiple strategies are now available for monitoring vascular access including measuring intra-access pressure and access blood flow, or screening for significant stenoses with Doppler ultrasonography. the ability of each strategy to detect significant stenosis is reviewed by looking at the evidence for both arteriovenous fistula (AVF) and arteriovenous grafts (AVG), separately. the majority of published literature involves AVG, and measuring access blood flow is the modality of choice. the best method for measuring flow is not known. For AVF, much less is known, and it is not clear whether monitoring will decrease the thrombosis risk and prolong access life. Recommendations for AVF cannot be made until more evidence becomes available. [source]


Favorable Long-Term Outcome after Liver-Kidney Transplant for Recurrent Hemolytic Uremic Syndrome Associated with a Factor H Mutation

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 8 2006
J. M. Saland
A male child initially presented with atypical hemolytic uremic syndrome (HUS) at the age of 4 months and progressed within weeks to end stage renal disease (ESRD). At the age of 2 years he received a live-related kidney transplant from his mother, which, despite initial good function, was lost to recurrent disease after 2 weeks. Complement factor H analysis showed low serum levels and the presence of two mutations on different alleles (c.2918G > A, Cys973Tyr and c.3590T > C, Val1197Ala). His survival on dialysis was at risk because of access failure and recurrent bacteremic episodes. Therefore, at the age of 5 years he received a combined liver-kidney transplant with pre-operative plasma exchange. Initial function of both grafts was excellent and this has been maintained for over 2 years. This report suggests that despite setbacks in previous experience, combined liver-kidney transplantation offers the prospect of a favorable long-term outcome for patients with HUS associated with complement factor H mutations. [source]


Prospective assessment of hemodialysis access patency after percutaneous intervention: Cox proportional hazards analysis

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 3 2005
John A. Bittl MD
Abstract Vascular access failure is the greatest limitation of successful hemodialysis, but the factors associated with long-term patency have not been fully elucidated. Outcomes in a consecutive series of 294 thrombosed or failing accesses [128 fistulas (43.5%) and 166 grafts (56.5%) in 179 patients] were analyzed with life table and multivariable Cox proportional hazards analysis. Initial success was achieved in 275 of 294 accesses (95.6%). The median patency after intervention was 206 days (interquartile range, 79,457 days). Fistulas had longer median patency after intervention than grafts (286 vs. 170 days). Nonthrombosed accesses had longer median patency than thrombosed accesses (238 vs. 136 days), but thrombosed fistulas had similar median patency as thrombosed grafts (140 vs. 136 days). The selective use of stents as a bailout for failed balloon dilatation did not significantly reduce long-term patency (196 days for stented accesses vs. 210 days for unstented accesses). Long-term patency was inversely related to final access pressure, but access patency was not related to the presence of central venous occlusions, graft age, patient age, sex, or diabetes. Catheter-based intervention of thrombosed and failing dialysis accesses significantly prolongs patency and usefulness of dialysis accesses. The expanding use of fistulas, improved detection of early access failure, and selective use of bailout stents should enhance long-term access patency. © 2005 Wiley-Liss, Inc. [source]