Influence of muscle training on resting blood flow and forearm vessel diameter in patients with chronic renal failure

BACKGROUND: Blood flow and vessel diameter are predictors of the success of vascular access procedures. This study investigated whether a simple exercise programme could influence these variables. METHODS: Twenty-three patients with chronic kidney disease were prescribed a simple exercise programme for one arm only; the investigators were blinded to the patients' choice. All underwent arterial and venous duplex imaging, handgrip strength and blood pressure measurements before and 1 month after the exercise programme. RESULTS: Twelve patients exercised their dominant and 11 their non-dominant arm. In the trained arm, the exercise programme resulted in a significant increase in handgrip strength, by a median (interquartile range) of 4 (0-8) kg (P < 0.001), and in the diameter of the brachial artery (0.2 (0.1-0.3) mm; P < 0.001), radial artery (0.3 (0.2-0.4) mm; P < 0.001), and cephalic vein (0.6 (0.4-1.2) mm in the forearm and 1.1 (0.4-1.2) mm above the elbow; P < 0.001). There was an increase in brachial artery mean velocity (3 (1-7) cm/s; P = 0.009) and peak systolic velocity (8 (1-15) cm/s; P = 0.020), despite a marginally lower systolic blood pressure (-8 (-16 to 0) mmHg; P = 0.007). There was no change in any of these parameters in the non-exercised arm. CONCLUSION: In patients with chronic kidney disease, forearm exercise increased blood flow and vessel diameters. This may be beneficial before vascular access formation.