Optimising the maturation rate of arteriovenous fistula (AVF) in patients with end stage renal disease (ESRD)

Abstract

A well-functioning Arteriovenous Fistula (AVF) has been shown to be the best modality for access in patients with end-stage kidney disease going for dialysis. Maturation of AVF is complex and depends on various biomechanical forces induced into the vascular system following creation of AVF. The focus of this thesis was to study factors that can lead to optimising fistula maturation in patients with End Stage Renal Disease (ESRD). The author looked into various factors related to patients’ demographics and clinical characteristics that are associated with the maturation process. The thesis also examined the evidence behind several debatable practices in formation of new AVFs. The optimal size of the vein diameter used in creating the anastomosis was evaluated. Comparisons between the end-to-side anastomosis technique and the side-to-side technique were assessed in a systematic fashion. Similarly, the differences between the one-stage versus the two-stage techniques in formation of brachiobasilic AVFs (BB-AVFs) were examined. In addition, the utility of using a neutrophil-lymphocyte ratio (NLR) as a fast blood test was evaluated. A third systematic review was conducted to examine the effect of post-conditioning on fistula maturation by means of far infrared (FIR) technology was conducted. There seems to be a lack of effective clinical, demographic and biological markers to reliably predict the outcome of a newly formed AVF. Vein diameter is a hugely important factor, arguably, the single most important predictor of maturation as fistulae created using veins of < 2 mm diameter are more likely to fail. Other factors such as female gender, diabetes mellitus, age, arterial diameter, surgical technique, and timing of the fistula formation in relation to starting HD sessions, can all be considered as additional predictors of AVF maturation. Side-to-side anastomosis has comparable maturation rates to end-to-side anastomosis. Similarly, two-stage BB-AVFs have similar maturation rates to those created using one-stage techniques. FIR has shown promising results in promoting fistula maturation; however, further studies are needed to evaluate its efficacy. Similarly, new emerging treatments - such as molecular biological manipulation - need further assessment.