Blood flow rate on NxStage unit for Patients with Catheters

I’m a care partner and we’ve been having arterial pressure issues when the blood pump is set at 350ml/min (as recommended). Even after reversing lines, I’ve been having to run the pump at 320 or even 300 to keep the aretrial pressure at or anywhere near the target of -240mmHg. (The dialysate rate is 10l/hr or 166.67 mL/min.) I know this is somewhat contrary to the NxStage training and their "Filtration Fraction” (where the blood flow rate needs to be 2-3 times the dialysate flow rate to compensate for the less efficient low flow rate of the dialysate). Anyone else running into a pump rate vs pressure issue with a catheter?

Mrozinski, are you on Facebook? This is exactly the sort of question our 5000+ HDC Facebook discussion group members can answer for you. Sadly, not as many folks post to the forums these days, though lots of folks read them. In general, a slower blood flow rate is better, but can mean a slightly longer treatment. (That’s actually also better.)

Okay, I just let you into the group! Welcome!

I found a curriculum for prescribing hemodiaysis for nephrologists developed by the American Society of Nephrology. It discusses NxStage flow fraction.

They’re recommending a blood flow rate of 400, just not doable with a catheter.

Guidelines developed by the kidney community define standard blood flows as 300 or more and low flows as less than 300. Catheters can have recirculation or blood flow issues that affect dialysis adequacy. Transonic is a company that manufactures a device that measures the actual blood flow and recirculation in HD catheters. Here’s information from that company. It might be worth asking the dialysis clinic if it would be worthwhile to do this measurement.
https://www.transonic.com/applications/hemodialysis-vascular-access/hemodialysis/catheter-adequacy/

Here’s information on other types of vascular access for dialysis. Because of flow problems and the higher risk of infection with catheters, a fistula or graft would be better options. See Module 8 on vascular access here:
https://www.kidneyschool.org/mods/