Fistula Maturation: A Slow Process Resulting in Chronic Catheter Placement and Higher Interventional Costs
By Tej M. Singh, MD, MBA
El Camino Hospital, Mountain View, CA USA
Editor’s Note: Dr. Tej Singh is a vascular/endovascular surgeon with a strong understanding of vascular program build out and is committed to growth and expansion of healthcare quality and affordability. Dr. Singh is currently the Director of Vascular Surgery at El Camino Hospital, Mountain View, CA USA with a strong research interest in Fistula maturation for renal disease.
We recognize that millions of patients worldwide are impacted by renal disease and renal failure leaving no choice but to place the patient on dialysis. With dialysis, however, come some major challenges. Dialysis options include central catheters, peritoneal dialysis or hemodialysis via fistulas.
AV fistulas require fistula maturation in order to allow for use of the fistula as an access point for dialysis. Successful fistula creation results in easy repetitive cannulation and adequate blood flow needed to support dialysis. Unfortunately, development of fistulas is a slow process that leads to chronic catheter placement and extra interventional costs plaguing our healthcare system. The specialist suggests patients do some form of exercise, including hand-arm exercises, in order to increase rate of fistula maturation. Those exercises include: Use of hand grips, weighted wrist flexions, stress balls, resistance bands, weights, etc. and involve a series of repetitive movements aimed at increasing the blood pressure flowing through the fistula. Specialists may recommend other exercises including using the other hand to squeeze the bicep of fistula arm, hindering blood return and causing fistula to dilate. In many instances, the patient does not perform these exercises because of the time it takes to do these exercises, confusion and frustration.
Intermittent Compression: We now know that extensive research has shown that intermittent compression can help dilate veins after fistula placement via possible mechanisms including wall tensile stress or nitric oxide release. Fist Assist™ (FA) was developed and created to help study the clinical role of pneumatic compression on fistula dilation. Recently, a large clinical efficacy study was completed at MS Ramaiah Medical Center in Bangalore India. Those results were presented in New York City at the 2016 VEITHsymposium.
The Study: One week after AVF creation, the Fist Assist™ was applied 15 cm proximal to the AVF in order to apply cyclic compression (60 mm Hg). 40 patients were test subjects and 17 were sham controls. Patients wore the device at home for 6 hours per day. Vein size was measured and recorded at 30 days by duplex measurement. Clinical results (percentage increase) were recorded and tested for significance.
No patients experienced thrombosis or adverse effects. Patient compliance and satisfaction was high. After 1 month, the mean percentage increase in vein diameter in the FA treatment group was significantly larger (p=0.05 than controls in the first 5 mm segment of the fistula. Even more impressive was the early rapid enlargement of forearm fistulas compared to upper arm at all segments (p<.05) at one month. All fistulae treated with FA are still functional with no adverse outcomes.
Early novel, non-invasive devices like Fist Assist™ may have clinical utility to create functional fistulae development and decrease costs as they may assist in maturation. The Fist Assist™ device is an external, medical wearable that can apply intermittent pressure on a specific arm vein to help dilate the vein after fistula placement in a simple non-traumatic way to insure vein enlargement and dilation.