I'm recearching the use or not of using the arterial pressure monitoring during dialysis. Our unit uses both venous and arterial monitoring, many units do not. If you do not, why not?

At our unit we are getting ready to try pre pump art. monitoring again,with better education than people had the first time it was tried here.At that time it was hated because air kept getting in systems whenever there was a flow problem, and dialyzers were clotting off. I think arterial flow problems were easier to ignore or gloss over without the art monitoring. In my years, I have noticed that some people never seem to grasp that setting BFR at 450 doesnt mean that you are getting BFR 450, and explaining seems in vain. The monitor, which gives incontrovertible evidence of high neg pressures will help with this segment of the dialysis caregivers. Good luck, I will be interested in your findings.

quote:

Originally posted by Dare to HD:
At our unit we are getting ready to try pre pump art. monitoring again,with better education than people had the first time it was tried here.At that time it was hated because air kept getting in systems whenever there was a flow problem, and dialyzers were clotting off. I think arterial flow problems were easier to ignore or gloss over without the art monitoring. In my years, I have noticed that some people never seem to grasp that setting BFR at 450 doesnt mean that you are getting BFR 450, and explaining seems in vain. The monitor, which gives incontrovertible evidence of high neg pressures will help with this segment of the dialysis caregivers. Good luck, I will be interested in your findings.

Will you please explain your preception of 450 BFR setting doesn't mean actual 450 BFR?
Thanks for your imput, resources are not readily available.

emma,

The BFR displayed on the machine is only "theoretical" and is a calculation that the machine does based on the RPM of the pump and the size of the pump segment. The pre-pump negative arterial pressure affects the actual delivered BFR because it is an indication that the pump segment is not able to refill after each stroke of the pump so in essence, the more negative the arterial pressure is the lower the actual delivered BFR (despite what the machine display reads).

It would be very helpful if the machine manufacturers would include an algorithm in the calculation that looked at the arterial pressure and then display the actual delivered BFR.

Chuck

Chuck,

Gambro's Phoenix machine does do that. It displays both blood pump speed and actual blood flow which is, like you said, derived from a simple formula using the blood pump speed and arterial pressure (or lack there of should I say?). Hopefully, others will follow this example.

BTW... Dare to HD, I know what you mean about explaining this. I can imagine it being similar to teaching a 3 year old physics.

We utilize Transonic monitoring for BFR and access flows. We have done this now for 6 years, before the Transonic was FDA approved.
Ultrasound and Ultrasound dilution gives precise monitoring for these values as well as Card. Output. Dare to HD is absolutely correct. The non-achievment of BFR is the dirty little secret that the industry ignores. We have dialyzed transients that have 500 bfr @ home unit but when Transonic measuring is done , they are lucky to get 350. This has a clinical concern in that the increased turbulence can caused shortened RBC lifespan. Few permacaths can actually achieve a 400 bfr.