Introduction: It is assumed that identification and correction of asymptomatic stenoses in the vascular access circuit will prevent thrombosis that would require urgent intervention to continue... Show moreIntroduction: It is assumed that identification and correction of asymptomatic stenoses in the vascular access circuit will prevent thrombosis that would require urgent intervention to continue hemodialysis treatment. However, the evidence base for this assumption is limited. Recent international clinical practice guidelines reach different conclusions on the use of surveillance for vascular access flow dysfunction and recommend further research to inform clinical practice.Methods: The FLOW trial is a double-blind, multicenter, randomized controlled trial with a 1:1 individual participant treatment allocation ratio over two study arms. In the intervention group, only symptomatic vascular access stenoses detected by clinical monitoring are treated, whereas in the comparison group asymptomatic stenoses detected by surveillance using monthly dilution flow measurements are treated as well. Hemodialysis patients with a functional arteriovenous vascular access are enrolled. The primary outcome is the access-related intervention rate that will be analyzed using a general linear model with Poisson distribution. Secondary outcomes include patient satisfaction, access-related serious adverse events, and quality of the surveillance process. A cost effectiveness analysis and budget impact analysis will also be conducted. The study requires 828 patient-years of follow-up in 417 participants to detect a difference of 0.25 access-related interventions per year between study groups.Discussion: As one of the largest randomized controlled trials assessing the clinical impact of vascular access surveillance using a strong double-blinded study design, we believe the FLOW trial will provide much-needed evidence to improve vascular access care for hemodialysis patients. Show less
The vascular access is the Achilles' heel of hemodialysis. This thesis focuses on the maturation and long-term outcomes of arteriovenous fistulas and compares them to arteriovenous grafts. Also the... Show moreThe vascular access is the Achilles' heel of hemodialysis. This thesis focuses on the maturation and long-term outcomes of arteriovenous fistulas and compares them to arteriovenous grafts. Also the results from the LIPMAT-study are presented, a randomized controlled trial in which improvement of arteriovenous fistula maturation using liposomal prednisolone was evaluated. Finally, cardiac effects of arteriovenous fistulas are explored. Show less
The main objectives of this thesis were to investigate the association between kidney disease and venous and arterial thrombosis and to provide insight in the mechanism of the association between... Show moreThe main objectives of this thesis were to investigate the association between kidney disease and venous and arterial thrombosis and to provide insight in the mechanism of the association between kidney disease and thrombosis. Furthermore, the mortality risks for hemodialysis patients with catheter, fistula and graft vascular accesses were investigated. Our studies showed that kidney disease was associated with an increased risk of venous thrombosis. We showed that patients with chronic kidney disease stages 1__3 (early stages) had an almost 2-fold increased risk of venous thrombosis as compared with subjects without chronic kidney disease. We also showed that patients with a severely decreased kidney function (estimated glomerular filtration rate <30 ml/min) had a 6-fold increased risk of venous thrombosis as compared with persons with a normal kidney function. Furthermore, it was shown that dialysis patients have increased risks of myocardial infarction and ischemic stroke. Dialysis patients with a catheter had increased mortality risks as compared with dialysis patients with an arteriovenous access (fistula or graft). An important mechanism for the increased thrombosis risk in patients with a kidney disease could be hypercoagulability (increased factor VIII and von Willebrand factor levels). Show less
