The use of pre-blood fluid in the reduction of filter clotting in dialysis is well known, but it is also known to reduce the efficiency of the dialysis abilities.
Could you please explain how your unit overcomes the drawback of the use of pre-blood fluid, and how the use of Filtration Fraction determines the use of pre-blood fluid? Some units determine that pre-blood fluid is not needed if the Filtration Fraction is below 30%.
Does this not then save the unit money if pre-blood fluid is not used? Also, it has been stated that in the use of Heparin in Dialysis, the APTT is irrelevant in the ability to stop the filter clotting off. What APTT therapeutic range does your unit run at?
Any information provided would be appreciated.
Thank you Ali for your input on this subject, I will read them with interest.
Hi Jeremy
We use the Prisma Flex system. I don´t know what system you are talking about. In our department we only use post-filter treatments. We compensate the concentrating effect of this modality with the PBS fluid. We have not seen much difference in the efficacy and complications between pre and post filter treatments. We try not to go above 25% filtration fraction. However, this is a single center experience. Respecting to anti-coagulation we are using heparin aiming to a post-filter aPTT between 60 and 80 seconds and having good results in what concerns to filter life span.
Before the Prisma Flex system we used the old Prisma system and at that time we used to perform pre-filter treatments. I remember we did not have any trouble achieving adequate treatments. The greater problem was filter life span.
Best regards
Eduardo Sousa
Hi Eduardo, Thank you for your response to my question. With regards to pre-blood solution, it is stated that there can be a reduction in efficience of upto 15%, it was this solution that I refered to be compensated for. Also, Filtration Fraction, can you please tell me how you manually calculate this. Another source states you don't need PBS with a filtration fraction below 30%. Regards Jeremy
Hi Jeremy
We a have a calculator from Gambro (now Baxter) designed for the Prisma Flex system. Based on that calculator we have designed a protocol for the first treatment day. Regarding to the reduction in efficiency, we only use post-filter to overcome that issue. From our experience that reduction does not affect our treament goals. Is this really important to you? Do you see much difference between the two modalities?
Best regards
Eduardo Sousa
Hi Eduardo,
thank you for your kind input on this subject, and please accept my apologies in the delay in my response.
We use pre blood solution with our filters on most patients, but in my study of this I have noted that in certain patients when the TMP reaches 250 to 300, the filter membrane becomes dysfunctional, with the patients urea and creatinine increasing, rather than decreasing as you would expect. This to me is a waste of resources, especially in times of health care hardship. With TMP’s reaching about 200-300, if the pre-blood solution is stopped (when the patients filter APTT is therapeutic), then the TMP drops.
I have also noted that running Dialysate and Replacement to make 20-25ml/kg/hr, or 25-30ml/kg/hr on those with frequent interruptions, filtration is more effective, at less cost. Don’t get me wrong, I have no problem with filters clogging off, it proves they have done their work, especially in septic patients. But when filters clot off after a short while due to inadequate clotting’s, that is the real frustration.
Regards
Jeremy
Hello jeremy
1-By one machine do you have this problem or with all machines you have high TMP during pre dialyzer fluid ?
2-How long does it work ( pre dilution modality ) when it starts allarming ?
3-Did you have similar problem while using post dilution ?
4-Did you try changing dialyzer ?
regards
- Badges
- Science topic
- Similar topics
- Medicine
- Disease
- Infectious Diseases