BLOOD TEST TIMING AND DIALYSIS

[balapandian]

Hi all,

When to perform tests like - Pottasium, phosporus, sodium, total count, Hb - before or after dialysis?

I wish to know how heparin and extra fluid in the blood (pre-dialysis) affect blood test results.

because of heparin, the dialysis technician told me to avoid taking blood tests post-dialysis, for atleast 1 day

Pls give your suggestions.

[cattlekid]

I do home hemo and we do most of our blood work prior to dialysis and prior to heparinization.  So it goes like this:

pre-dialysis:  HgB, pre-BUN, other pre-dialysis labs (two purple tubes, one tiger tube)
heparinize
dialysis
post-dialysis:  post-BUN (green tube)

[bevvy5]

For hubby's dialysis, all the regular monthly tests, phosphorus, potassium, calcium, CBC are done with pre dialysis blood.  So we insert his needles and then draw the blood, then flush with saline and then heparin.  Saline and/or heparin will basically make any tests done useless and will likely raise all sorts of red flags becuase the results will be nonsensical.  Don't ask me how I know that - LOL!!

For normal post bloodwork, they just check urea, creatinine, phosphorus, potassium, basically to check how effectively he's dialysing.

Other tests like iron and stuff that are done every three months are done using pre dialysis blood.  Greg is nocturnal, so fasting bloodwork like cholesterol, etc. is taken from post bloodwork, done in the morning.

[RichardMEL]

The reason to not do regular bloods post-D is that, obviously, you come out (mostly) squeaky clean and your levels (should) be all close to normal right after D - the only reason you might want to run labs after D is as a test of how effective the D is on you, but the norm is to do it post D - the best is before D but not after a weekend so you get a "normal" snapshot of where you're at with your levels before D - because you need to get a guide to how much the toxins are building up and what effect they could have on your system - this in turn would determine any changes to meds or D reigime you may require to help get things back into the normal range - so yes, pre-D is the preferred way.

Indeed when my monthly bloods were taken it was always taken out of the line before the machine was started (this was in-centre) so it's literally right before your blood goes into the cleaner. This is also when tx bloods were taken, but that was less critical - just useful to do it all at once.

[AnnieB]

So we insert his needles and then draw the blood, then flush with saline and then heparin.  Saline and/or heparin will basically make any tests done useless and will likely raise all sorts of red flags becuase the results will be nonsensical.  Don't ask me how I know that - LOL!!

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