AVF Complication Rate Low, Study Shows
Arteriovenous fistulas should be created in patients before dialysis.
Nephrologists should not let concerns about complications delay arteriovenous fistula (AVF) creation, according to a Canadian study.
Findings showed that complication rates are low and clinicians have adequate time to correct problems prior to the start of dialysis, said lead investigator Catherine Weber, MD, a nephrology fellow at the University of British Columbia in Vancouver.
“We found that if you create a fistula early, you have time to make a second fistula if an event occurs, such as thrombosis or failure to mature, and thus the patient does not need a central venous catheter with its attendant complications,” Dr. Weber said.
An AVF should be placed in CKD patients when their creatinine clearance is less than 25 mL/min per 1.73 m2, serum creatinine level is greater than 4 mg/dL, or within 12 months of anticipated need, Dr. Weber advised. DOPPS II showed that despite most patients having adequate time with a nephrologist, the United States and Canada have an unacceptably high rate of catheter use.
She and her colleagues studied 323 patients who had an estimated glomerular filtration rate (eGFR) of less than 25 mL/min per 1.73 m2. Of these, 125 underwent AVF creation prior to starting dialysis and 198 did not. In the group of 125, the investigators determined the rate of complications (infections, steal syndrome and neuropathy) and adverse events (thrombosis and failure to mature).
Compared with patients who did not have AVFs created before starting dialysis, those who did were somewhat younger (mean age: 66 vs. 69 years) and tended to have a different etiology of CKD, a lower burden of CVD (42% versus 64%), and more time under a nephrologist's care (18 vs. 14 months).
Of the 125 patients, 87 (70%) underwent successful AVF creation, 14 (11%) suffered an AVF thrombosis, and 24 (19%) had a non-maturing AVF, for a primary failure rate of 30%. Younger age independently predicted AVF thrombosis and a history of CVD independently predicted a non-maturing AVF.
Of the 14 patients with an AVF thrombosis, 13 had a second AVF created compared with only 10 of 24 patients with a non-maturing AVF. Four patients suffered a second subsequent event. Overall, infections, steal syndrome, and neuropathy occurred in 3%, 2%, and 1% of patients, respectively.
Six months into dialysis, the group with early AVF creation had a higher rate of AVF use (74% vs. 40%), and the rate of catheter use was nearly threefold lower compared with pa-tients whose AVF was created after starting dialysis (19% vs. 56%).
Nephrologists, Dr. Weber said, should not delay AVF creation. “You should not wait three or six months and see what happens,” Dr. Weber told Renal & Urology News. “When the GFR is declining, the patient needs to be referred for placement of vascular access. To ensure optimal outcomes, there needs to be a close liaison between the nephrologist and the vascular surgeon, especially if an event or complication occurs.”