Urea-based recirculation validation of the symmetrical palindrome catheter

Background: High blood flow and low recirculation rates are central for adequate haemodialysis. A new symmetrical tip has been invented promising efficient haemodialysis even if the ports are reversed.

Objective: To evaluate access recirculation of the 'palindrome' catheter and to report initial experiences in a clinical setting.

Material and methods: After implantation of the new catheter in 20 patients (male: 14; female: 6; mean age 72 ± 12.2), access recirculation was evaluated using the urea-based recirculation test. After 30 minutes of haemodialysis, ultrafiltration was stopped and arterial and venous samples were taken. Afterwards, the blood flow rate was reduced to 120 ml/min. Another systemic arterial blood sample was taken 10 seconds after the blood pump was switched off.

Results: All 20 interventions were performed successfully without complications. The average recirculation rate was 8.1% with a median of 2.5% ranging from 0 to 85.8%. Recirculation rates under 5% were measured in 13 patients and more than 10% recirculation were found in two patients. The median of days between catheter implantation and recirculation assessment was the day following implantation.

Conclusion: The new symmetrical catheter presented low recirculation rates in a clinical setting. Since there is just a single tip, fluoroscopic placement in the right atrium is facilitated.