Effect of Isometric Preoperative Exercise on Vascular Caliber and the Maturation of Autologous Arteriovenous Fistulas. Randomized Clinical Trial

A good vascular access (VA) is vital for hemodialysis (HD) patients. The start of HD with autologous arteriovenous fistula (AVF) means higher survival, lower sanitary costs and complications. The distal forearm AVF is known as the best option but not all patients are good candidates for this surgery, and there is a primary failure rate between 20 and 50% published in literature.

The choice of the optimal AVF for each patient is conditioned mainly by the anatomical and hemodynamic characteristics of the artery and the vein chosen to perform the anastomosis. These characteristics can be modified by performing physical exercise Some vascular access guidelines suggest the performance of isometric exercises in the pre and postoperative period of the AVF confection. However, there is very little data in literature on the possible efficacy of preoperative exercise, although small published observational studies point to an improvement in the venous and arterial caliber. Regarding the postoperative exercises, they do seem to improve maturation, however the degree of evidence in literature is low and there is no consensus on the exercise protocol to follow.

We present an open-label, multicenter, prospective, controlled and randomized study in order to evaluate the usefulness of preoperative isometric exercise (PIE) in pre-dialysis patients or in prevalent HD with indication of performing a new AVF. The randomization will be 1: 1, one group of patients will perform PIE for 8 weeks and the other group of patients will be a control group. The main purpose will be to evaluate if there is a lower rate of primary failure in the PIE group compared with control group.