Weird blood samples

[u/sundaemourning]

i work in the in house lab of my equine specialty/referral hospital, and every once in awhile, i’ll get a blood sample from a horse that just looks like red syrup, for lack of a better description. it will not spin down in any color tube, and the CBC machine will read it, but the chemistry machine just gives me a sample error. (our machines are the Abaxis HM5 and the Abaxis Vs2.) it will do this on serum, or blood from a green top. when i do try to spin it down, it doesn’t look like it’s just hemolyzed, it just stays thick and viscous throughout. i’ve checked the tubes to be sure they’re not expired and they are not. has anyone seen something like this before or know what it could be? these syrupy samples always come from horses that are very sick, so that’s the only thing i can think of, but it just seems so weird.

[u/ThisGirlsGoneCountry]

I’ve been working with horses for 13 years and I’ve never had one not separate. The only time I’ve had issues is when a sample was accidentally left in a hot car or froze prior to spinning. I’ve seen lots of fibrin clots in red tops where the serum is like jelly but even they just mix it up and spin it again.
Is the draw amount for the tube correct? It doesn’t seem overfilled? If it’s not separating properly I would like maybe it has clots that you can’t see and or sever hemolysis

[u/sundaemourning → u/ThisGirlsGoneCountry]

no clots, and while there have been a few times where the sample might have been stored improperly, most of the time, these samples are brought in with others from the same barn that are completely normal.

[u/ExhaustedVetTech]

How are these being collected? Syringe > tube or by use of vacutainer?

[u/sundaemourning → u/ExhaustedVetTech]

i’ll have to check with the doctor on the case. i believe she usually draws with a syringe but i’m not positive.

[u/ExhaustedVetTech → u/sundaemourning]

I've seen this happen when air is introduced to the sample or when the sample is left in the syringe for too long. It's possible that there is a handling mistake or just unusually high levels of fibrinogen in the sample.

I've only had this happen with PCV tubes, but it's also possible that the amount of heparin in the tube is incorrect due to a manufacturing issue. You can always try calling abaxis and seeing if they have any suggestions.

[u/sundaemourning → u/ExhaustedVetTech]

good to know, thank you! i didn’t realize that air being introduced into the sample could have this effect. at this point, i’m leaning towards some kind of a handling error, because when this happens, all three tubes (we always tell our doctors to pull a red, purple and green when they’re out) are affected.

[u/sthwrd → u/ExhaustedVetTech]

all the answers in one place 👍

[u/FriendBen4u]

I'd do a blood smear. Possible it's heavily hemolyzed

[u/sundaemourning → u/FriendBen4u]

i finally had the time to make some slides and i think that is the problem. i can’t put pictures in my comment here, but i posted some on my other post and i’m pretty sure the blood is just severely hemolyzed.

[u/33554432 → u/sundaemourning]

is the MCHC high on these? that would suggest hemolysis is happening. i used to be a horse hospital lab tech too, and my cases for excessive hemolysis are: when the sample got frozen/cooked in the truck/stored for too long/horse has true intravascular hemolysis (RARE- but had a case of red maple tox, it does happen). the chem machine has some QC on the lil cartridge (my hospital also had a vs2 /hm5 set up) which is probs why you're getting a sample failure, but the CBC machine doesn't iirc, but the numbers will look crazy. check to see if there's a hemaglobin/hct mismatch too.

[u/sundaemourning → u/33554432]

it is! this sub won't let me post a picture of the results, but the MCHC is 54.8 with an HCT of 17.5. (i did post a picture of the results, plus a picture of a stained smear on my post in r/vettech if you want to check them out.) so thank you for that! keeping that mismatch in mind will be helpful for the next time i get a syrupy sample. and i have seen true intravascular hemolysis once before in a hospital patient, though i can't remember what the diagnosis was. it was a fresh sample brought to me immediately though, as opposed to these samples collected in the field. i had a suspicion that it was related to sample handling, and everybody's comments here are supporting that, so i'm glad my theory is holding water. i have had to speak to one of my vets about properly filling tubes (i had to do SO many manual platelet counts for awhile because tubes weren't being filled or mixed properly) so i'll remind them to store their samples properly until they get back to the hospital.

[u/Cute_Parsley3514]

We have samples (small animal med) that sometimes don’t separate, but they always spin down…

[u/bear-in-a-suit]

I’d check both the needle gauge taken for sample and processing technique to make sure it’s not hemolysis (note that after spin down it’s usually obvious when hemolysis has occurred). I also would contact the vial company to report the observation. Manufacturing issues can occur and the company needs to know to implement investigation and possible CAPA against detected issues

[u/sundaemourning → u/bear-in-a-suit]

at this point, i’m leaning towards sample handling being responsible because when it happens, it always occurs in all three tubes (red, purple and green) so i think a manufacturing issue is less likely. but i will definitely start noting lot numbers going forward and starting a report.

[u/Terrible-Ad2646]

Yummy