Effect of preoperative isometric hand exercise on vascular caliber in patients with advanced chronic kidney disease -...

Arteriovenous fistula (AVF) remains the preferred vascular access for hemodialysis, yet maturation failure is common and preoperative strategies to optimize vessel caliber are poorly standardized. This study hypothesizes that isometric exercise, when implemented preoperatively can enhance vascular caliber, thereby improving AVF creation and maturation.

This single-center, prospective randomized controlled trial enrolled 54 patients with CKD stage 4-5 scheduled for vascular access creation at Chulabhorn Hospital, Bangkok. Participants were allocated 1:1 to an 8-week isometric exercise regimen (grip strengthener and pétanque ball; n = 27) or control (n = 27). Vascular caliber was assessed by duplex ultrasound at baseline, 4, and 8 weeks. The primary outcome was change in cephalic vein arm diameter at 8 weeks. Secondary outcomes included changes in other vessel diameters, grip strength, AVF feasibility, AVF type, and 12-week maturation rate.

Baseline characteristics were comparable except for higher CAD prevalence (44.4% vs. 18.5%, p = 0.040) and antiplatelet use (40.7% vs. 14.8%, p = 0.033) in the control group. The exercise group demonstrated a significant increase in cephalic vein arm diameter at 8 weeks (p = 0.045). Radiocephalic AVF creation was significantly more frequent in the exercise group (93.8% vs. 58.3%, p = 0.026). Baseline cephalic vein arm diameter was the strongest independent predictor of AVF feasibility (adjusted OR = 3.63 per mm, 95% CI [1.56, 8.47], p = 0.003). AVF maturation rates did not differ significantly between groups.

An 8-week preoperative isometric exercise protocol significantly improved cephalic vein arm diameter and increased radiocephalic AVF creation rate, a clinically meaningful shift that preserves proximal venous capital for future vascular access procedures. No significant difference in short-term AVF maturation was observed, likely reflecting the premature 12-week follow-up and composition effect of more radiocephalic procedures in the exercise group; adequately powered trials with extended follow-up are warranted.

The study was registered with the Thai Clinical Trial Registry (number: 20230913004) on 13 September 2023.