Needle infiltration of arteriovenous fistulae in hemodialysis: risk factors and consequences.

BACKGROUND

Needle infiltration of arteriovenous fistulae is a common problem in US hemodialysis units. This study evaluated the frequency of fistula infiltration, its risk factors, and clinical consequences of this complication.

METHODS

Using a prospective computerized vascular access database, we identified all patients with a major fistula infiltration sufficiently severe to prolong catheter dependence for dialysis. These patients were compared with a control group without fistula infiltration. We also quantified subsequent access outcomes in patients with infiltrations.

RESULTS

During a 5-year period, 47 patients had a major fistula infiltration, representing a 5.2% annual rate. On multiple variable logistic regression analysis, the likelihood of fistula infiltration was associated strongly with patient age (odds ratio, 1.039/1-year increment; 95% confidence interval, 1.016 to 1.062; P = 0.0007). Fistula infiltration was not associated with sex, race, diabetic status, peripheral vascular disease, body mass index, or fistula location. New fistulas (< 6 months in age) were more likely in patients with infiltrations compared with patients without infiltrations (43.5% versus 20.5%; odds ratio, 2.98; 95% confidence interval, 1.61 to 5.54; P = 0.0004). Each major fistula infiltration resulted in a mean of 2.4 diagnostic tests, surgery appointments, or interventions. Fistula thrombosis occurred in 12 patients (26%). Median prolongation of catheter dependence for dialysis in patients with major infiltrations was 97 days.

CONCLUSION

Needle infiltration of fistulae is more common in older patients and with new fistulae. These infiltrations result in numerous procedures, as well as prolongation of catheter dependence for more than 3 months.