lab draws through central lines

[morrisonrn]

I can't find a policy on central line lab draws at my facility, but nurses have told me you need to first flush with 10 ccs of ns and then waste 10 ccs. Just wondering if anyone knows the rationale behind this. Thanks:)

[Spatialized]

when you're drawing for a blood culture do you still discard the waste? or do you use the waste for the blood culture

For blood cultures we take whatever is in the line, and don't waste. The rationale I was given was that in case something was growing in the line we would be able to get a culture of it instead of fresh blood. (i.e. the line is the source of the infection which makes sense as it is a portal of entry.) Besides, for blood cultures we get more than is in the line so you do get a good assay.

Cheers,

Tom

[greatshakes]

Hi Gail Anne and others

As a student I was told by the phlebotemist that a specimen of blood was to be taken from a CVC and one of the nurses told me I needed to put in a n/s flush first. I went to get a flush but I didn't do it as the pathology asssistant came back then and told me they didn't want the line flushed first and she took the blood. She drew a small amount off first and then obtained the specimen. Apparently it affects the results of the test or something. The nurse and I both learnt something that day. He was surprised too and thought this was normal practice.

[christvs, DNP, RN, NP]

I'm so glad I read this because just today I drew blood from a triple lumen catheter (I'm a new RN) & was wondering exactly why we discard the first tube. I knew I had to do it, I just didn't know why. That makes sense that it may be contaminated with bacteria, just like for a clean catch urine sample we ask the pt to pee a little first in the toilet and to then pee in the specimen cup, to make sure it is not contaminated.

-Christine

[Larry77, RN]

Hi Gail Anne and others

As a student I was told by the phlebotemist that a specimen of blood was to be taken from a CVC and one of the nurses told me I needed to put in a n/s flush first. I went to get a flush but I didn't do it as the pathology asssistant came back then and told me they didn't want the line flushed first and she took the blood. She drew a small amount off first and then obtained the specimen. Apparently it affects the results of the test or something. The nurse and I both learnt something that day. He was surprised too and thought this was normal practice.

So the phlebotemist obtained the blood from the central line? That's a big no no in Wash State...has to be an RN (or PA, ARNP, MD of course).

If you are looking for sepsis I would think you would want to waste the first sample to make sure the growth is not from the cap.