Effect of Pre-operative Forearm Exercises on Arterial Venous Fistula Maturation and Blood Flow

This study will investigate the effect of pre-operative exercise on hemodynamics in the fistula artery and vein, Pre and Post Arteriovenous Fistula Formation as well as the suitability of Cannulation of Arteriovenous Fistula at 12 weeks Post Surgery. This is a randomised control study with 20 patients each in the Control arm (Group A) or the Exercise arm (Group B). The subjects will be randomised into 1:1 into one of the two groups. The patients will have an ultrasound doppler vein mapping done prior surgery and the necessary follow up visits.

The incident and prevalent population on renal replacement therapy for End Stage Renal Disease (ESRD) is steadily increasing in Singapore as well as other countries worldwide. Around 85 - 90% of the prevalent dialysis population is on Hemodialysis and Arteriovenous Fistula (AVF). AVF is considered the Gold standard for safe and effective vascular access for hemodialysis treatment due to its low rates of complication. However, Primary Failure rate of AVFs remain high at around 20 - 25% depending on the site of the surgery, contributed by several factors including the diameter of the artery and the vein used for AVF formation. If Pre-operative exercise improves the hemodynamics of the AVF and aids the maturation rate in our study, it can be incorporated into clinical guidelines to reduce the primary failure rate of AVF. Even though, there is sufficient evidence to support the beneficial role of the forearm exercises on fistula blood flow and maturation, there are no studies looking at the effects of Pre-Operative Exercise on AVF maturation. Our Study is aiming to fulfil this gap in knowledge.

Patient randomized are required to squeeze a soft ball 10 times for a set. They are required to perform 3 sets of 10 squeezes each at a 1 Minute interval. 3 sets of exercises to be performed twice in the Morning and Evening, for a total of 6 weeks.

Inclusion Criteria: Age >=21 to <= 90. Chronic Kidney Failure patients with Estimated Glomerular Filtration Rate (eGFR) less than 20mls/min. Haemodialysis is chosen as their modality of renal replacement therapy. Exclusion Criteria: Potential fistula vein diameter <= 3mm (with application of tornique) on initial vein mapping. Known Left ventricular ejection fraction of less than 20% on Echo diagram. Previous stroke effecting the AVF arm. Calcified brachial or radial arteries and/or duplex evidence of stenosis of >= 50%

Kong S, Lee KS, Kim J, Jang SH. The effect of two different hand exercises on grip strength, forearm circumference, and vascular maturation in patients who underwent arteriovenous fistula surgery. Ann Rehabil Med. 2014 Oct;38(5):648-57. doi: 10.5535/arm.2014.38.5.648. Epub 2014 Oct 30.

Salimi F, Majd Nassiri G, Moradi M, Keshavarzian A, Farajzadegan Z, Saleki M, Nikpoor A, Ghane M. Assessment of effects of upper extremity exercise with arm tourniquet on maturity of arteriovenous fistula in hemodialysis patients. J Vasc Access. 2013 Jul-Sep;14(3):239-44. doi: 10.5301/jva.5000123. Epub 2013 Jan 3.

Uy AL, Jindal RM, Herndon TW, Yuan CM, Abbott KC, Hurst FP. Impact of isometric handgrip exercises on cephalic vein diameter in non-AVF candidates, a pilot study. J Vasc Access. 2013 Apr-Jun;14(2):157-63. doi: 10.5301/jva.5000116. Epub 2012 Dec 12.

Rus RR, Ponikvar R, Kenda RB, Buturovic-Ponikvar J. Effect of local physical training on the forearm arteries and veins in patients with end-stage renal disease. Blood Purif. 2003;21(6):389-94. doi: 10.1159/000073441.