Point-of-care ultrasound for assessing arteriovenous fistula maturity in outpatient hemodialysis

Abstract

Background: Point-of-care ultrasound in end-stage renal disease is on the rise. Presently the decision to cannulate an arteriovenous fistula is based on its duration since surgery and physical exam. This study examines the effects of point-of-care ultrasound on decreasing the time to arteriovenous fistula cannulation, time spent with a central venous catheter, and the complications and infections that arise. Methods: Prospective point-of-care ultrasound patients were recruited between January 2015 and January 2018, while retrospective data (non-point-of-care ultrasound) were collected via chart review from patients who had fistula creation between November 2011 and May 2014. Patients had point-of-care ultrasound within 3 weeks after arteriovenous fistula creation and were followed for 1 year. Arteriovenous fistula cannulation was initiated when the following parameters were met: diameter > 6 mm (with no depreciable narrowing of more than 20% throughout), depth < 6 mm, and length > 6 cm. Demographic data, as well as time to cannulation and central venous catheter removal, number of infections, complications, and interventions were compared between point-of-care ultrasound and non-point-of-care ultrasound groups using unpaired t-test, chi-square, and Fisher exact test statistical analysis. Results: A total of 37 patients with new arteriovenous fistulas were followed by point-of-care ultrasound compared to 29 non-point-of-care ultrasound patients. Point-of-care ultrasound patients had earlier cannulations (35.5 vs 63.3 days, p < 0.05), shorter central venous catheter duration (68.2 vs 98.3 days, p < 0.05), and less infections (12 vs 19) without differences in complication compared to the non-point-of-care ultrasound. Conclusion: Point-of-care ultrasound facilitates early and safe arteriovenous fistula cannulation leading to a reduction in central venous catheter time and risk of infection. Point-of-care ultrasound may also aid in earlier identification of complications and difficult cannulations.