Volume vs. Time

[Restorer]

Over the last couple months, I've been adjusting my cycler settings and working to be able to take larger fill volumes. Now I'm getting to the point where my total volume is maxing out with respect to the 10 liters I set up the machine with each night. I'm wondering if anyone has experience with the difference between using higher fill volume and longer dwell times vs. lower fill volume and shorter dwell times, while keeping the same total volume and dwell time?

That is, let's say my options are thus:
1). 1600 ml fill, 6 cycles, 1 hour dwell time - total volume of 9600 ml, total dwell time of 6 hours plus fill/drain
2). 1370 ml fill, 7 cycles, 51 minute dwell time - total volume of 9590 ml, total dwell time of 5 hours, 57 minutes plus fill/drain

Is the choice going to be purely dependent on how fast of a transporter I am, assuming I can take the larger fill just fine?

[Hanify]

Good luck with that.  I don't even know how to change my machine, so I always leave it up to my renal nurses.  Are they happy that you change yours?  Will I one day be so experienced I would consider it?  I'm sure others will have some thoughts.

[koutsounel]

I am not sure what the fill volume does excactly, but I have the impression that larger fill volumes offer you more dialysis. What I do know is that longer dwells tend to remove more toxins (if for example potassium is up) wheras shorter dwells remove more fluids (if your bp is up). My son is a baby,for his age group dwells are between 45 minutes and an hour - but I think something similar applies to adults - It's the fill volume that changes! You might see the difference in your uf and bp when you have the longer dwells.

[BigSteve]

I don't know about the Newton cycler, but on the Baxter machine it is possible for the PD nurse to
use Baxter's software to predict possible scenarios. The variables such as volume, time and number of
exchanges can be entered to determine what the Kt/V for various combinations might be.  The only
problem is that you can't go beyond Baster's peramiters such as singe fill volume maximum is 3000 ml.
My neph agreed to let be go up to 3500 mls, but this could not be programmed into the machine.

[Restorer]

Since I posted, I had a 24 collection to get my Kt/V, and then my PD nurse had the data to plug into that program, so he showed it to me. Apparently I'll need to increase my fill volume and add a fill during the day in order to break 2.0 Kt/V.

[Hanify]

Temporarily or will you have to always do the extra.  What a shame.  At the moment are you empty during the day or extraneal?

[Restorer]

This is probably permanent adjustment. I'm going to look into using the PD+ mode on the cycler so I don't have to use a manual bag - just connect to the cycler in the evening, let it fill me, then go on pause and disconnect until I settle in for the night.

Right now, aside from the manual fill, I'm dry during the day.

[Hanify]

My system only got changed a month or so back.  I was full during the day, but also did a manual bag.  Then they changed me to doing my last fill with an extraneal bag.  It's fantastic not having to do that manual bag, and seems to actually work better than before.  My first drain is always about 2.5 litres whereas before it used to only be about 1.9 because the fluid had started going back through.  It's meant that I can drink at least 500mls more a day which is amazing!  I think you should ask about the extraneal option.