I reached out to a friend who used to work for NxStage. What she told me is that there is NOT another filter. The timing of the dialysate had the dialysate finished before ultrafiltration was finished. There is NO problem with this except if it is too long, your dad could get cold because there is no warm dialysate going through.
In a conventional treatment they may say not to use the dialysate if only fluid needs to be removed, but most people need more cleaning. With NxStage being gentle, it is NOT a problem to just use the dialysate longer.
If the treatment will be longer because of the UF, the dialysate rate can be slowed down so both end at the same time. Ask the nurse to explain how to do this. For example: if the prescription is to use 30 liters of dialysate and it runs @ 10 liters per hour the dialysate will be done in 3 hours. If you slow it down to 8 liters per hour the dialysate would last 3.75 hours.
Thank you so much for your feedback and for being my first responder (other than the âwelcomeâ bot).
I understand what you mean about lowering the dialysate flow rate. In my dadâs setup, once Iâm ready to start treatment (touching the kidney button just to be clear) I increase blood flow rate to 400. I then increase dialysate flow rate which I was trained to just max out to what it will allow based on blood flow rate. At 400, dialysate maxes out at 10.0L/hr. After a few minutes, once Iâve confirmed all is well, my dadâs BP is holding g well I then increase blood flow rate to 450. Again, I max dialysate out at the allowable which is 11.3L/hr.
So, what youâre suggesting is leaving the dialysate flow rate at 10.0L/hr and leaving it there even after increasing blood flow rate to 450 (not increasing to the 11.3L/hr). This would slow the dialysate such that it would exhaust at 3 hours treatment. Hopefully I understood you correctly.
Now, when dialysate exhausts for his treatment and he still has another hour of treatment, though there is no other filter, excess fluids are still continuing to be âpulledâ out (since it appears not to be filtering at this point) and disposes of out the waste line? Only reason I ask is because I was always under the impression that dialysate is required for dialysis treatment as it is the medium by which the process takes place. If correct, I believe blood & dialysate flow opposite one another through the artificial kidney and is what enables the removal of toxins through those miniscule filter tubes. Absent dialysate, fluids do continue to be removed by some manner. Am I understanding correctly?
I shared what you wrote with my friend. She said that you need to talk to your nurse. If he/she doesnât understand, the NxStage nurse can help. She said it sounds like you know what youâre doing and understand the process. From what you wrote she said youâre using flow fraction for treatment so would need orders to change dialysate flow to accommodate longer treatment when needed by the amount of ultrafiltration needed.
She told me that you are asking what is the difference:
dialysis/filtration of toxins does require dialysate and is accomplished by osmosis and diffusion.
fluid removal/ultrafiltration does NOT require dialysate and is accomplished by negative pressure pulling fluid from the blood so it can go down the drain.
So she said to discuss this with your nurse and get orders on how to change the amount of dialysate to come closer to the ultrafiltration OR to get your dad to cut back on his fluid intake. Is his fluid intake higher than it used to be?
The dialysis clinicâs dietitian may be able to suggest ways to reduce thirst and/or limit fluid. For example, cutting back on salt and controlling blood sugar (if diabetic), and having the doctor review and revise meds that have a side effect of thirst can help reduce fluid intake. There are some tricks patients have reported at this link.
Fantastic! Thank you so much for reaching out to your NxStage friend again. So glad to know that all the ti.es dialysis exhausted, my dad was never just sitting there waiting until the end of treatment time in vain. Weâve entertained the idea of him taking his weight when dialysate exhausts and then again after treatment, as usual, to see if there was a difference. We never did . It was always just as easy, if not easier just to let the clock run out & call it at that time.
Yes, these machines are actually quite fascinating! Iâve just sat and looked into it and sometimes wondered who ever had the time to sit down & think up this piece of equipment. Just the timing and sensitivities alone wouldâve been a miraculous feat. Good to know and better understand how fluid continues to be removed after dialysate is exhausted. Interesting that the machine creates a low pressure for fluid removal. These may or may not work in similar ways but when I was younger, I used to fly small aircraft privately. An aircraftâs wings are smooth and flat across the bottom. But the top of the wing is shaped such that air traveling over the top of the wing has to travel faster than air underneath to then meet with air on the backside of the wing. As a result, a low pressure is created underneath the wing. Low pressures rise. Hence, flight is achieved. Perhaps the low pressure in the dialysis machine in someway causes excess fluid to be lifted from the blood at which point it is then extracted. I may be way overthinking this but hey, the machine really is quite an amazing contraption.