Pre-Operative Forearm Exercise On Arteriovenous Fistula Mauration

Effect Of Pre-Operative Forearm Exercise On Arteriovenous Fistula Mauration and Blood Flow

To investigate the effect of pre-operative exercise on

1. Hemodynamics in the fistula artery and vein, pre and post AV fistula formation
2. Suitability of cannulation of AV fistula at 8weeks

Aim: To investigate the effect of pre-operative exercise on hemodynamics in the fistula artery and vein, pre and post AV fistula formation as well as the suitability of cannulation of AV fistula at 8weeks post sugery

Methodology: This is a randomised control study with 20 patients each in the exercise arm and the control arm. The subjects will be randomised 1:1 into one of the two groups. Chronic Kidney failure patients with eGFR less than 20mls/min and have chosen Haemodialysis as their modality of renal replacement therapy will be included the study. All the subjects will have an ultrasound doppler vein mapping done prior to entering the study.

The exercise protocol for the intervention group will be to squeeze a soft ball 10 times for set and perform 3 sets of 10 squeezes each at an 1 minute interval. Three sets of exercises to be performed twice in the morning and twice in the evening, for a total of six weeks.

All patients will have a follow up ultrasound doppler of the AV fistula at 8 weeks and 16 weeks post-surgery, looking at the AV fistula vein diameter, arterial diameter and blood flow rate. All the subjects will also be seen by a single vascular surgeon following the scan, to assess the suitability for AVF cannulation.

Significance of the proposed study and benefits: A well functioning arterio-venous fistula is the gold standard vascular access for Hemodialysis patients due to its low rates of complications. The primary failure rate of the AVFs remain high at around 20 -25%, contributed by several factors including the diameter of the vessels. If pre-operative exercise improves the hemodynamics of the AV fistula and aids the maturation rate in our study, it can be incorporated into clinical guidelines to reduce the primary failure rate of AV fistulas.

Inclusion Criteria:

1. Chronic Kidney failure patients with eGFR less than 20mls/min
2. Chosen Hemodailysis as their modality of renal replacement therapy

Exclusion Criteria:

1. Potential fistula vein diameter less than 3mm (with application of tornique) on initial vein mapping
2. Known left ventricular ejection fraction of less than 20% on Echocardiogram
3. Previous stroke effecting the AV fistula arm
4. Calcified brachial or radial arteries and/or duplex evidence of stenosis of >50%