Foamings at drain site

[Chris Pearson]

Has anyone come up with a way of having a low volume (say <1L) of bleach on the machine shelf that is both H&S and financially acceptable.
I seem to remember working with Ian M at Kings a couple of years ago but the cost of producing and supplying in 1L cans was extortionate.
BR
Chris

[Andrew Gardner]

We have a throw away dialysate cartridge (Quanta SC+) with no need for any disinfectant and still see drain froth. After working in Dialysis for 30 yrs+ why am I hearing about or seeing this phenomenon now ? that's perplexing. I wonder if its a differing concentrate additive formulation ? Interesting to hear what acid and bicarb is being used by the people seeing foam.

[Chris Pearson]

Hi Andy,
Is there a permanent drain tube after the disposable cartridge which isn't being disinfected ?

[Andrew Gardner]

further down the line but we see foaming before that.

[Chris Pearson]

Did you get it with Citrasate ?

[Andrew Gardner]

Never used citrasate in any of the clinics only in the lab.

[Chris Pearson]

That explains it then

[Chris Bates]

I have long suspected that this is due to proteins in dialysis waste. I believe that one way of showing that a solution may have proteins in it is to see if it froths when shaken.
Not much in the way of proteins and amino-acids should get through a dialyser, but with high flux dialysis and high convective flow we may get more in the dialysate than we think.
 
One of our doctors suggested a Biuret test might show this - or one of its more sensitive variants (Yes I went on Wikipedia).

Maybe someone should try this on a sample of dialysate, with or without a sample of the froth.
I suspect that even if this proves to be the case we will not be able to eliminate the frothing. We may be able to reduce it by performing regular bleach rinses on the machines to reduce the residue in the drains where there is a significant air gap at the drain outlet.

I have seen frothing at many locations over many years but I can't put my finger on what combination of circumstances were common to each location. However the build up of the disgusting gelatinous drain blancmange does seem to be reduced in situations where regular bleach cleaning is performed.

I may talk to our QC labs to see if they could perform this test.

Chris

[Chris Bates]

p.s. this paper   http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.830.5954&rep=rep1&type=pdf    seems to show that quite a lot of proteins may be lost during dialysis, possibly more if using PAN membranes.

[Chris Bates]

External drain at one unit - Nice

[Chris Pearson]

I talked with a old(ish) dialysis Sage earlier this week about this thread,he seemed to think that it may be caused by passing the protein enriched spent dialysate through a valved connector at the end of the drain line creating a sort of venturi effect like a cream frother they use in restaurants,sound feasible .

[Chris Bates]

Sounds plausible, however the picture I posted above is from a unit with open tubes on the drain pipes rather than Walthers