Systematic review of interventions to increase the use of arteriovenous fistulae and grafts in incident haemodialysis patients.

BACKGROUND: Patients who commence haemodialysis (HD) through arteriovenous fistulae and grafts (AVF/G) have improved survival compared to those who do so by venous lines. OBJECTIVES: This systematic review aims to assimilate the evidence for any strategy which increases the proportion of HD patients starting dialysis through AVF/G. DATA SOURCES: Medline, Embase, Cochrane Central and Scopus. STUDY ELIGIBILITY, PARTICIPANTS AND INTERVENTIONS: English language studies comparing any educational, clinical or service organisation intervention for adult patients with end stage renal failure and reporting incident AVF/G use. STUDY APPRAISAL AND SYNTHESIS: Two reviewers assessed studies for eligibility independently. Outcome data was extracted and reported as relative risk. Reporting was performed with reference to the PRISMA statement. RESULTS: Of 1272 studies, 6 were eligible for inclusion. Studies varied in design and intervention. Formal meta-analysis was not appropriate. One randomised controlled trial and two cohort studies assessed the role of a renal access coordinator. Two cohort studies assessed the implementation of qualitive initiative programmes and one cohort study assessed a national, structured education programme. Results between studies were contradictory with some reporting improvements in incident AVF/G use and some no significant difference. Quality was generally low. CONCLUSIONS: It is not possible to reach firm conclusions nor make strategic recommendations. A comprehensive package of care which educates and identifies patients approaching dialysis in a timely manner may improve incident AVF/G use. An unbiased, robust comparison of different strategies for timing AVF/G referral is required.

Quality and readability of online patient information for abdominal aortic aneurysms.

OBJECTIVE: We assessed the quality and readability of patient information for abdominal aortic aneurysms (AAAs) on the World Wide Web, as accessed from the United Kingdom. METHODS: Web sites returned by a simple Web search using the three largest search engines by market share were objectively and subjectively assessed for quality and readability. The Internet search engines Google, Yahoo!, and Bing were interrogated for the term "abdominal aortic aneurysm" and the first 50 hits screened. Organization type and Health on the Net status were recorded. Each unique site containing AAA information was scored for quality using the University of Michigan Consumer Health Web site Evaluation Checklist by two authors, and readability was calculated using the Flesch Reading Ease (FRE) score. Subjective content assessment was also undertaken. RESULTS: Of 150 hits, 112 were relevant, with 55 unique sites for assessment. Overall, the FRE score was 39 (range, 29-47) and the Michigan score was 36 (range, 25-56), with good interobserver agreement (r(s) = 0.83; P = .01). Michigan and FRE scores were poorly correlated (r(s) = 0.064; P = .6). Sites containing discussion on the merits of endovascular/open repair and the concept of an intervention threshold had the highest Michigan scores (58.5 [50-59.75] vs 28 [13-36.5]; P < .001). Search engine ranking, Health on the Net status, country of origin, and organization type did not affect quality or readability. CONCLUSIONS: The current quality and readability of online patient information for AAAs is poor and requires significant improvement. Clinicians treating patients with AAAs should be aware of the limitations of the online "lay literature."

Ischemic skin ulceration complicating glue embolization of type II endoleak after endovascular aneurysm repair.

The optimal treatment for type II endoleaks remains unclear. The present report describes a case of ischemic skin ulceration after glue embolization of a type II endoleak with challenging access in a multiply comorbid 82-year-old woman with an expanding aneurysm sac 3 years after endovascular aneurysm repair. Embolization was performed from a proximal position with an n-butyl cyanoacrylate/Ethiodol mixture to allow flow into the endoleak because direct sac puncture was hazardous. One week after intervention, an eschar, which progressed to superficial necrosis as a result of partial nontarget delivery of sclerosant, developed over the left iliac crest. The eschar was self-limiting, with complete resolution by 6 months.

Altered platelet reactivity in peripheral vascular disease complicated with elevated plasma homocysteine levels.

Elevated plasma concentrations of the sulphur-containing amino acid homocysteine (Hcy) is associated with increased risk of atherosclerosis and arterial thrombosis. The mechanism by which Hcy exerts these effects has yet to be fully elucidated, although a variety of possible mechanisms have been proposed, including endothelial dysfunction or haemostatic abnormalities. However, the influence of Hcy on platelets, cells central to the atherothrombotic process, has never been addressed directly in patient studies. Here, the influence of mild hyperhomocysteinaemia (hHcy) on platelet function was explored in patients with peripheral occlusive arterial disease as evidence by intermittent claudication. Claudicants (n = 39) were assigned to one of two subgroups depending on their plasma Hcy concentrations. hHcy claudicants had plasma Hcy concentrations of 18.9 +/- 1.0 microM (n = 24), compared to 11.3 +/- 0.5 microM for normohomocysteinemic (nHcy) claudicants (n = 15) and 12.6 +/- 0.7 microM for age-matched controls (n=15). Platelet function was evaluated ex vivo in both groups and compared to age-matched controls. Platelet activation and sensitivity to nitric oxide-mediated inhibition was assessed by platelet fibrinogen binding and P-selectin expression. At low concentrations of adenosine diphosphate (ADP; 0.1 microM) and thrombin (0.02 U/ml), platelets from hHcy claudicants were more reactive than those from age-matched controls, but not nHcy claudicants. Agonist-induced P-selectin expression was significantly raised in hHcy claudicants compared to all other groups. Interestingly no differences were observed between nHcy claudicants and age-matched controls, indicating that claudication per se did not affect platelet function. Since platelet activity in vivo is determined by the exposure to both agonists and antagonists, we subsequently tested the sensitivity of platelets to inhibition by nitric oxide (NO), using the same platelet markers. Platelets from hHcy claudicants were significantly less sensitive to GSNO (1-100 microM)-mediated inhibition than all other groups. GSNO (1microM) induced 42.6 +/- 10 and 39 +/- 11.5% inhibition of ADP-induced fibrinogen binding for the nHcy claudicants and age-matched controls, respectively. However, in hHcy claudicants only 16.4 +/- 9.7% inhibition was observed, significantly less than the other groups (P < 0.01). Again no differences between nHCy claudicants and controls were observed. These results suggest the presence of claudication alone does not influence platelet function but if complicated with mild hyperhomocysteinemia, the sensitivity to agonists is increased, and more importantly, their sensitivity to inhibition is greatly reduced. The overall effect would be an increased propensity for platelet activation. The presence of even mildly elevated plasma Hcy could dramatically increase thrombotic risk.