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For haemodialysis patients there is always a risk of a blockage of the access to the bloodstream. Periodical measuring of the blood flow can timely signal an imminent blockage, upon which a dotter procedure can prevent complete blockage. This strategy is already successfully applied at the MUMC+, although the available scientific literature does not confirm this success yet. The described strategy could possibly be improved by increasing the measuring frequency by means of using innovative, in the dialysis equipment integrated techniques. Two techniques were studied: one of these turned out comparable to the present golden standard measuring method with regard to reliability.

Patients with kidney failure who become dependent on haemodialysis will often develop an arteriovenous fistula (AVF), a negative effect of which being the occurrence of complications after a few years.This doctoral research project focusses on two long-term complications related to AVFs. The first long-term complication this dissertation focusses on is a high blood flow (high flow access (HFA)) which may lead to excessive burdening of the heart. Surgical banding for HFA, a method often applied in the past, is shown to be less effective than presumed. The recurrence rate of HFA is 50% after 1 year of follow-up. Revision using distal inflow (RUDI), a new technique, appears to be much more successful, as the recurrence rate is only 16% after 1 year of follow-up. A second complication this dissertation focusses on is a severely reduced perfusion of the hand (haemodialysis access-induced distal ischaemia (HAIDI)). Generalised arteriosclerosis and increased arterial stiffness are found to largely contribute to HAIDI. Another cause of HAIDI is ‘loss’ of blood pressure through ‘side’ veins around the AVF which are not punctured for dialysis. Knotting these ‘side’ veins is found to be an effective treatment method.

A well functioning vascular access is necessary for successful hemodialysis treatment (a therapy that replaces the kidney function). Vascular access can be created with an arteriovenous fistula (AVF), a connection between a coronary artery and a vein. The risk of treatment failure increases, however, if the patient has small or bad vessels. In that case an arteriovenous graft (AVG), an artificial blood vessel that is subcutaneously attached between a coronary artery and a vein, can be a solution. Research in this dissertation shows that, looking at the life span, patients with bad vessels indeed benefit from placing an artificial AVG as vascular access for dialysis.

To be able to connect haemodialysis patients to an artificial kidney a connection is surgically made between a coronary artery and vein in the arm (AVF). The exact location of this new vessel access is crucial for success. If an AVF is not made on the location that is optimal for the patient, this can result in a too low blood stream, which makes the vessel access not usable for haemodialysis, or, on the opposite, in a too high blood stream which results in heart problems or insufficient blood flow in the hand. Additional interventions are then necessary to realize a usable vessel access. The researchers developed a computer model that can predict the blood stream after placement of an AVF and that can thus help select the optimal location. The computer model was capable of selecting in 16 out of 21 patients before the operation the same vessel access as a very experienced surgeon. The model could be valuable during the determination of the optimal AVF location, especially for an inexperienced surgeon.