Siphoning problems with Baxter Cycler?

[PaulBC]

Slightly off-topic, but I had an inadvertent siphon with a Baxter cycler. At least I think. There was no danger, because it all happened after the session was over and disconnected.

Normally, we dismantle and dispose of the set when we're done, but in this case, I had left everything in place with clamps open except for the patient line. I removed the set from the machine before turning it off and put it on top (like I usually do). There were three bags including the heated bag, and I had turned one of the non-heated supply bags upside down at the beginning to avoid a potential kink.

When I finally had a chance to look at the bags over an hour later, it appeared that the heated bag was absolutely empty (sucked dry) and one supply bag was still mostly full, while the other was empty.

The session appeared to complete without any alarms, and my first thought was that it had drawn dialysate mostly from one bag. This struck me as worrisome, but fortunately the bags were all the same concentration.

I wondered how I could have missed this, though I did not remember examining the bags closely before. I would have expected the supply bags to be equal volume and the heated bag to be at least half full.

When I picked up the set, I saw some siphoning action, and then it hit me that after I disconnected, the heated bag might have back-siphoned into the supply bags and for whatever reason might have siphoned preferentially into the one I had not turned over. This seems a more likely explanation than the cycler drawing preferentially overnight, because I'm sure I would have noticed (but either way I am now going to make sure supply bags are always the same height and orientation).

Pretty scary and sort of funny in retrospect (since everything seems fine now). I will make sure to note the state of the bags ever morning now, and close all the clamps just like the machine tells me to do.




EDIT: Moved from "Dialysis: Humor, Pictures, Stories and Poems" to the more appropriate "Dialysis: Home Dialysis" Board.

NOAHVALE  MODERATOR

[Charlie B53]

Sounds like your drain/fill program leaves some dialysate left over at end of treatment.

My program is adjusted fill volume so as to use all fluid from all bags, nothing left over.

You may want to ask your PD Nurse if this is correct.  It may be just fine.

[PaulBC]

The PD nurse works out a program that delivers a specific amount of dialysate, which may not exactly match the amount in a certain number of 5 liter bags. If it's a little over and we need another bag, there could be a significant amount left. This is for a pediatric patient, so maybe it is handled differently.

My program is adjusted fill volume so as to use all fluid from all bags, nothing left over.

Right now, we are so close to the exact amount that it worries me. I watched the last step in final fill this morning, and it sounded like slurping the last drink of soda, leaving bubbles in the heated supply line (but not the the patient line).

However, the therapy log shows all the final fills being delivered to within a few ml, so I think it's OK. Is this how it works for you?

[jcanavera]

I've watched my wife's cycler pretty closely so I have a good handle on this.  Here is what I've observed.  She uses 3, 6 liter bags along with a 2 liter Extraneal  bag for the final fill.  The cycler draws from the heated bag and refills the heater bag during dwell time.  With a tidal flow program our nightly flow can vary up to about 1500 ml each night.  This means that the heater bag can have fluid left in it even though the 2 supply bags are sucked dry.  What the cycler does is during the final dwell, the contents of the heater bag is pumped dry.  This leaves the three 6 liter bags dry.  The cycler then pumps the entire contents of the Extraneal bag into the empty heater bag.  Dependent upon the program set, Your final fill of Extraneal will be pumped into you.  My wife's fill is 1500 ml of Extraneal.  Once her treatment is done, there will be 500+ ml of unused Extraneal left in the heater bag.

If you turn the machine off and remove the set, the machine is no longer putting pressure on the different set valves in the set itself.  That means the fluid can siphon into any bag in which the clamps are left open.  That's why the machine tells you to close all clamps before you disconnect the tube that goes to your catheter and before you turn the cycler off.

Hope this helps.

Jack