Daily fluctuation in RBCs / HGB

[Lbrown]

Hi guys,

My HGB drops around 27-28 points or so in 2 weeks, so I've always assumed it drops about 2 points a day. I've always wondered if it ever went up but since I only get a CBC once every 2 weeks, I would never know.

So yesterday I had my regular CBC and today right before my transfusion I had another one (this was ordered by the dr, they've never done this before, I told the nurse they should be putting blood IN! LOL)

Anyway, here's the results:


Fri: HGB 93, WBC 1.3, Neut 0.8, Plat 88
Sat: HGB 96, WBC 1.8, Neut 1, Plat 95

And my $64,000 question is - how much does HGB fluctuate on a daily basis? I mean, I sort of want to have a party (better results - and in my red cells!) but I don't want to party like it's 1999 if my results are due to something stupid like dehydration or a natural flux. Theoretically, my HGB should have been 91 today.

Thanks,
Deb

[triumphe64]

There is always a "lab error" of about a point (0.5 each way?) or 10 for you. At least that is what I'm always told. I worked most of my career in accounting and always have trouble with internalizing this concept.

[riccd2001]

Over the years, when hospitalized, the Lab techs would do my Hgb 2 to3 times a day around the units transfused. Of course YMMV but the average "bump" would be 10 to 12 points (g/L) depending on the actual volume in the bag. The drop for me is 1 point per day, and that has been the same with me for the last four years.

[Lbrown]

Wow Triumphe - I'm with you. 5 points either way sounds horrendously inaccurate to the point of why bother testing.

riccd2001 - I had the CBC before the tfx. I usually estimate 10 points per 200 ml, and then work out what my HGB should be afterwards based on volume. I get counts done every 2 weeks and the HGB always drops, usually around 27 points. It also used to drop every time when I had weekly counts done. It would be interesting (but real inconvenient) to get daily counts. Do you get monthly transfusions, or 1 unit every 2 weeks?

I've never seen my count go up much, so I am hoping it is not lab error, but I realize it could be.

What about the WBCs, from 1.3 to 1.8 is almost a 40% difference in one day. I think WBCs and platelets probably fluctuate more than RBCs, and I didn't do anything that would have caused dehydration in 24 hrs.

Probably never know. Hope it happens again though! LOL.

Deb

[triumphe64]

I did a quick Google search and came up with this. There were other results, but I did not check them.

http://www.masimo.com/pdf/SpHb/LAB5447A.pdf

[Lbrown]

Oh well - so much for keeping track of counts!

[Lisa V]

I agree about the margin of error. When Ken checked in for his second ATG, his initial CBC showed his Hgb at 7.7. I had been charting his counts all along, and even though his Plts and RBCs were in free-fall at that point, I had a pretty good feeling for how quickly they were falling, and that represented a much faster drop than I'd been seeing. I managed to talk them into retesting just the Hgb, and the second count (an hour later) came back as 8.2. That's quite a difference.

Monitoring the counts over time gives you a good feel for the general direction things are going, but it's important not to get hung up on a single number.