I keep failing Conductivity checks on pureflow

[TonyH]

I wonder if anyone else has had the same pureflow issue as me. I have been having dialysis at home since start of March and since then have had nothing but problems with the pureflow. It keeps failing the conductivity. It will work for a couple of times and then fail. All the components have now been changed several times but nothing seems to work. The last time it was repaired was last week, I put the sak on while I was at work and got home to the dreaded beeping telling me that it had failed. Has anyone else had the same issues and what sorted them. I think the engineers are now out of ideas as to what is wrong - the water and pipes have all been tested and passed. I am using the bags at the minute but the hospital don't want me to be on them all the time due to the cost. Thanks in advance for any help / advice

[boswife]

When i failed conductivity, i was told that i needed to do my testing within 2 hours of finish of fill.  The reasoning was that the PF puts off something after a few hours of sitting that will make it a false fail (as in"apperar" a fail), but that you have to take  a fail as a fail and not use that batch anyway.  So now, i make sure i am within that 2 hour range and have not failed since. 

[TonyH]

Hi Boswife,

Thanks for the reply. With the machine we use the conductivity is done during the last 20 mins of making up the batch. You don't test it. The machine automatically passes or fails. If you have a pass you then test the chloramines yourself - I think that is what you are referring too. we very rarely get to the Chloramine stage as the conductivity fails befroe then.

[silverhead]

After I had failed several Conductivity tests I really started paying close attention to the bags and noticed that on all the failures the tiny tubes inside the bags were bunched up near the end, after that I spent time trying to make sure those tubes were moved to a position closer to the center of the bag and no more failures. I think there may have been a failure on quality control during the manufacture of the bags.....
Tom

[greg10]

Hi TonyH, Welcome to the forum. 

I think Silverhead has something there about the proper arrangement of tubing whilst filling the SAK.  As you know, the SAK is just a 15:1 or so concentrated dialysate.  If the Pureflow doesn't properly reconstitute the concentrate, you will fail the conductivity test because the dialysate will be too concentrated to be used.  If the water source checks out then most likely it is the tubing that is pinched and not properly filling the SAK.  If you ever stick around and watch the SAK fill (yes, it is like watching paint dry), you will see the tubings unfold and move about.  Make sure it is not pinched against the SAK as the SAK is filling up and follow the new SAK-3 series instructions on how to properly uncap the green folded section of the tubings.

The other possibility is that there is something wrong with the Pureflow unit itself, a defective pump or filling programming, that prevents the proper amount of purified water from filling the SAK. 

Finally, do you have proper water pressure at your house?  It may be a possibility that insufficient water pressure can affect the proper amount of water from filling the SAK.

I wonder if anyone else has had the same pureflow issue as me. I have been having dialysis at home since start of March and since then have had nothing but problems with the pureflow. It keeps failing the conductivity. It will work for a couple of times and then fail. All the components have now been changed several times but nothing seems to work. The last time it was repaired was last week, I put the sak on while I was at work and got home to the dreaded beeping telling me that it had failed. Has anyone else had the same issues and what sorted them. I think the engineers are now out of ideas as to what is wrong - the water and pipes have all been tested and passed. I am using the bags at the minute but the hospital don't want me to be on them all the time due to the cost. Thanks in advance for any help / advice

[boswife]

   you are so right about that..  But  I have another response for your (real) issue, and not that it's what your problem is  but ................  When we installed our lines, we went up about 3ft and a few inches 'up' to a drain line.  That couple of inches was enough that if the line bumped up at all, we would fail the "conductivity" test. They had us pinch one of SAK lines while attempting to fill (i wont direct you on that) and if it would make the flow work, then that might be the issue.  Well, it did, and so we went and lowered the black line about an inch and we have never had that problem again.  They said the waiste line was ment to go a max of 3ft high (which we wernt told when techs came to approve of our setting)  So, wheather this will help ya at all i dunno, but given ya another thought anyway 

[Bill Peckham]

Ok I only say this because I've done it too often to mention but the clamps are all open? the orange clamp particularly?


If the clamps are open then you could try the old slosh the dialysate around trick. Manually stir up the bag by punching it a few times. Back when I ran on the B Braun with jugs of dialysate I'd have to shake them up mid run sometimes.

[lmunchkin]

We had alot of Conductivity failures at first, but what Silverhead said is exactly what our problem was. The placement of the two tubes on the sak may be what is happening. When I placed them where it started to fill up, I placed them up and in the center.  The chances of them getting kinked or pinched are much better now, than before.  We have no more conductivity failures!

Surely, the engineers at Nxstage knew this, which make me think it is in the programming of your unit!

lmunchkin

[TonyH]

Thanks for all your replies. We have tried sloshing the bag and have also made sure the line's arent kinked. The water pressure has also all been tested. Today the engineers are here again changing the heater underneith the pureflow. If that doesnt work I dont know what will happen as they have will have exhausted everything by then.  I will let you know how it goes ;0)

[boclark54]

We were having that problem too at one time. Finally got a Tech that told me to clamp white line (water outlet) take off and hold over container and unclamp, small amount of liquid drains out, put back on and open clamp and start again, when it rechecks it may pass. Don't get it as much now but works everytime.

[Zog]

We had three or four batches fail in a row using a variety of different lots of SAKS and eventually had to get a different machine.  It sounds like you have done this.  The techs did mention the waste line height issue, however we have been running the Pureflow in that location for three years so we didn't think that was it.  We had a low water pressure problem about two years ago that messed up batches.  We couldn't wash clothes or dishes or take a shower while a batch was being made or it would fail.  We fixed that problem by adjusting the house PRV and switching to some brass fittings to connect the machine to our clothes washer box.  We had a galvanized splitter that had clogged up with calcium deposits.

I think they had some serious manufacturing defects with the new three digit SAK's.  I believe they have fixed them all now.  We had about 6 SAK's with cracked and split lines at the green sleeves.  These would leak and flood the tank/house.