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Optimizing Access Surgery In Senior Hemodialysis Patients

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

Status
Active, not recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05911451
Acronym
OASIS
Enrollment
166
Registered
2023-06-22
Start date
2019-11-01
Completion date
2026-03-31
Last updated
2025-05-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Vascular Access Complication, Hemodialysis Access Failure, Dialysis Access Malfunction, Arteriovenous Fistula, Arteriovenous Graft, Central Venous Catheter Related Bloodstream Infection

Brief summary

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.

Detailed description

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.

Interventions

It is recommended to create the arteriovenous fistula 3 to 6 months before the expected start of hemodialysis treatment using locoregional anesthesia. It is recommended to use minimal venous and arterial diameters of 2mm for radiocephalic fistulas and 3mm for brachiocephalic and brachiobasilic fistulas. It is recommended to avoid creating an arteriovenous fistula at the same side as a pacemaker, central venous catheter, or arterial stenosis. It is recommended to use the following order of preference for arteriovenous fistula creation: radiocephalic fistula as first choice, brachiocephalic fistula as second choice, and brachiobasilic fistula as third choice.

It is recommended to implant the arteriovenous graft 2 weeks before the expected start of hemodialysis treatment under antibiotic prophylaxis. Implantation of an early-cannulation graft is recommended for patients who require more urgent start of hemodialysis to avoid the use of a temporary central venous catheter. It is recommended to use minimal arterial and venous diameters of 3mm and 4mm, respectively. It is recommended to avoid placing an arteriovenous graft at the same side as a pacemaker, central venous catheter, or arterial stenosis.

It is recommended to place a tunneled central venous catheter just before the start of hemodialysis treatment under local anesthesia, with conscious sedation if preferred by the patient. The catheter should preferably be placed in the right internal jugular vein with ultrasound-guided puncture and fluoroscopy control under sterile conditions. According to usual practice at the trial center, catheters may be implanted by surgeons, interventional radiologists, or nephrologists.

Sponsors

ZonMw: The Netherlands Organisation for Health Research and Development
CollaboratorOTHER
Maastricht University Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Parallel group, multicenter randomized controlled trial.

Eligibility

Sex/Gender
ALL
Age
65 Years to No maximum
Healthy volunteers
No

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)

Design outcomes

Primary

MeasureTime frameDescription
Access-related intervention rateVariable follow-up time of at least 1 yearThe number of access-related interventions required for each person-year of hemodialysis treatment. This outcome measure includes all percutaneous access interventions (including central venous catheter placement, removal and guidewire exchange, angioplasty, stent placement, and percutaneous thrombectomy) and surgical access procedures (including initial access creation, subsequent access placements if the first access failed, and surgical revisions to promote maturation or maintain long-term patency, including open thrombectomy) from randomization and treatment assignment until the end of the study period or death.

Secondary

MeasureTime frameDescription
Patient-reported outcome measures (2)Every 3 months in the first year after enrollment and in the first year after dialysis startShort Form Vascular Access Questionnaire (SF-VAQ)
Patient-reported outcome measures (3)Every 3 months in the first year after enrollment and in the first year after dialysis startEuroQol - 5 dimensions - 5 levels (EQ-5D-5L)
Health care costsEvery 3 months in the first year after enrollment and in the first year after dialysis startMedical Consumption Questionnaire
Access-related complicationsVariable follow-up time of at least 1 yearAccess-related complications requiring pharmacological treatment (Clavien-Dindo grade 2)
Days in hospitalVariable follow-up time of at least 1 yearThe number of days admitted to hospital or visiting out-patient clinics for any reason per person-year (including hemodialysis sessions).
MortalityVariable follow-up time of at least 1 yearAll-cause mortality
Patient-reported outcome measures (1)Every 3 months in the first year after enrollment and in the first year after dialysis startShort Form 12 Dialysis Symptom Index (SF-12 / DSI)
Assisted primary patencyVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
Secondary patencyVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
Primary functional patencyVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
Time until mature vascular accessVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
Time until functional vascular accessVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
The number of hemodialysis sessions with cannulation difficultiesVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis
Primary patencyVariable follow-up time of at least 1 yearOutcome measure registered for exploratory analysis

Countries

Netherlands

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026