Optimizing Access Surgery In Senior Hemodialysis Patients

Optimizing Access Surgery In Senior Hemodialysis Patients: a Multicenter Randomized Controlled Trial of Fistulas, Grafts, and Catheters

The number of elderly hemodialysis patients is growing. Vascular access complications are a major determinant of the quality of life and health care costs for these vulnerable patients. The three different types of vascular access, i.e. autologous arteriovenous fistulas, arteriovenous grafts, and central venous catheters, have never been compared in randomized controlled trials. This project will deliver the much-needed evidence to determine the optimal strategy for vascular access creation in elderly hemodialysis patients in order to deliver better health care at lower costs.

Objective: To compare surgical strategies for vascular access creation in elderly hemodialysis patients.

Hypothesis: Arteriovenous grafts and central venous catheters lead to fewer interventions, more quality of life, and lower health care costs than autologous arteriovenous fistulas.

Study design: Parallel group, multicenter randomized controlled trial.

Study population: Patients >65 years with a life expectancy <2 years who are expected to start hemodialysis treatment within 6 months or who have started hemodialysis treatment with a catheter in the past 6 months.

Study groups:

1. Autologous arteriovenous fistula creation
2. Arteriovenous graft implantation
3. Central venous catheter placement

Sample size calculation: 3x65 patients for superiority with multiplicity correction based on a clinically relevant difference of 0.80 interventions/year. Due to slow enrollment, follow-up time per participant was much longer than anticipated at trial initiation. After enrollment of 166 participants, calculations based on actual event and mortality rates showed that the trial had sufficient statistical power to detect a relative difference in event rate of 0.67, corresponding to an absolute difference below the minimal clinically relevant difference of 0.80 access-related interventions per year. Therefore, enrollment was closed at 166 participants.

Data analysis: Poisson regression analysis with time as off-set variable.

Inclusion Criteria:

1. Adult patients aged 65 years or older
2. End-stage renal disease with unlikely recovery of kidney function according to the attending nephrologist
3. Hemodialysis is the intended long-term modality of treatment for end-stage renal disease
4. Fit for vascular access surgery as determined by the local multidisciplinary vascular access team 5a. Expected to start hemodialysis treatment within 6 months at the time of treatment assignment; or 5b. Treated with hemodialysis for 6 months or less at the time of treatment assignment using a tunneled or non-tunneled central venous catheter for vascular access

6. Planning to remain in one of participating dialysis centers for at least 1 year 7. Suitable vascular anatomy for all types of vascular access based on duplex ultrasound of the arms, defined as:

• at least one suitable configuration for an arteriovenous fistula using minimal arterial and venous diameters of 2mm for radiocephalic fistulas and 3mm for brachiocephalic and brachiobasilic fistulas;
• at least one suitable configuration for an arteriovenous graft using minimal arterial and venous diameters of 3mm and 4mm, respectively; and
• at least one open internal jugular vein for a central venous catheter.

Exclusion Criteria:

1. Patent arteriovenous fistula or graft already in place
2. Prior unsuccessful arteriovenous fistula or graft vascular access surgery
3. Kidney transplantation planned within 6 months
4. Metastatic malignancies or other condition associated with a life expectancy of <6 months, in the opinion of the attending nephrologist
5. Unable to provide informed consent
6. Dusseux risk score <5, indicating an usually long life expectancy for elderly patients starting hemodialysis treatment (the Dusseux risk score was adapted for patients between 65 and 70 years by assigning -3 points to this age category)