Blood clotted

[kate47]

Hi my doctor took blood test to check my ESR levels. I got a call from the receptionist yesterday to say it needs repeated as the test could not be done due to my blood clotting. I have never experienced this before. Can anyone explain please? Thanks

[PMRpro]

The test is done on whole blood - a sample is put into a tall thin vertical tube and they watch how fast the red blood cells fall to the bottom. The most likely reason is the phlebotomist didn't mix the sample with the anticoagulant that is in the correct blood bottle or maybe they used the wrong bottle or it was faulty and didn't have the anticoagulant in it. ESR must also be done within 4 hours of taking the blood sample - that can damage the sample too.

[kate47 in reply to PMRpro]

Thank you

[LottieLou96]

Technically ESR should be done then and there, and a good sample has to be taken to avoid initial blood clotting, so a good flowing sample into the tube, the tourniquet not too tight etc. And then you have it up for an hour, with a line for time 0s and see where it has sedimented to after 60 mins, and measure it, gives your ESR. So ESRs are my bug bearer, when they aren't done immediately from sample being taken, because it's the first 60 mins to count, not hours down the line.

Small rant over.

Hope it helps slightly.

Lottie

[rubybelle12]

If you have the sample taken at the GP surgery, sometimes the transport may be delayed and by the time they get it to the lab the blood has clotted. This has happened to my sample in the past.

[loopy-lou]

I had exactly the same with my last blood test. I had to go back to have it done again which was annoying x